Ronald Borchardt


Ronald Borchardt
  • Distinguished Professor Emeritus
  • Department of Pharmaceutical Chemistry

Contact Info

Simons Biosciences Research Laboratories, Room 210
2093 Constant Avenue
Lawrence, KS 66047

Biography

Ronald T. Borchardt is a Distinguished Professor Emeritus of Pharmaceutical Chemistry at The University of Kansas- Lawrence. Professor Borchardt received his undergraduate education (B.S. in Pharmacy, 1967) from the University of Wisconsin-Madison and his graduate education (Ph.D. in Medicinal Chemistry, 1970) from The University of Kansas-Lawrence. After serving as a Postdoctoral Fellow at the National Institutes of Health (Bethesda, Maryland) from 1969-1971, Professor Borchardt returned to The University of Kansas as an Assistant Professor. In the 1970's Professor Borchardt was promoted through the academic ranks to the position of Solon E. Summerfield Distinguished Professor in 1981. He held this position for 34 years until his retirement in 2015. From 1983-1998, Professor Borchardt served as the Chairman of the Department of Pharmaceutical Chemistry in the School of Pharmacy at The University of Kansas. During his academic career, Professor Borchardt supervised the research of approx. 170 graduate students, postdoctoral fellows and visiting scientists.

Professor Borchardt's research interests have included both drug delivery and drug design. In the area of drug delivery, his interests include: (i) the development of epithelial and endothelial cell culture systems for the study of drug transport and metabolism; (ii) the development of rational strategies (e.g. prodrugs) to improve the transport characteristics of peptides and peptidomimetics; (iii) the elucidation of the chemical pathways of protein and peptide degradation; and (v) the development of strategies to stabilize biomolecules in pharmaceutical formulations. Professor Borchardt's interest in drug design has focused on the design and synthesis of inhibitors of an enzyme (S-adenosylhomocysteine hydrolase) that plays a key role in regulating biological methylation reactions, which are crucial for the replication of some viruses and parasites.

Professor Borchardt contributions to the development and validation of cell cultures for studying drug transport across the intestinal mucosa and the blood-brain barrier have been particularly significant. His pioneering work in the late 1980s lead to the introducing of Caco-2 cells as a model of the intestinal mucosa. This cell culture model is now widely used by scientists in pharmaceutical/biotechnology companies and in academic and government laboratories worldwide. Based upon his medicinal chemistry background, Professor Borchardt has more recently utilized this in vitro cell culture model for studying how structure influences transport of drugs across the intestinal mucosa.

During his academic career Professor Borchardt has received numerous awards and honors for his teaching and research accomplishments including: Established Investigator from the American Heart Association (1974-1979); Sato Memorial International Award from the Pharmaceutical Society of Japan (1981); Mortar Board Outstanding Educator Award (1980), Dolph C. Simons, Sr. Research Award in the Biomedical Sciences (1983), the Louise Byrd Graduate Educator Award (1997) and the Chancellors Club Career Teaching Award (2005) from The University of Kansas; Fellow of the American Association of Pharmaceutical Scientists (1988) and the American Association for the Advancement of Science (1995); Citation of Merit from the University of Wisconsin (1989); Meritorious Manuscript Awards (1991, 1998), Research Achievement Awards in Biotechnology (1993) and Medicinal Chemistry (1994), and Distinguished Pharmaceutical Scientist Award (1997) from the American Association of Pharmaceutical Scientists; Takeru and Aya Higuchi Memorial Lectureship Award from the Academy of Pharmaceutical Sciences and Technology of Japan (1993); Paul Dawson Biotechnology Award (1997) and Volwiler Research Achievement Award (1998) from the American Association of Colleges of Pharmacy; Hoest-Madsen Medal (1999) from the International Pharmaceutical Federation; Distinguished Service Award (1999) from the FASEB Research Conference on Biological Methylation; the Millennial Pharmaceutical Scientist Award (2000) from the Millennial World Congress of Pharmaceutical Sciences; the Research Achievement Award in the Pharmaceutical Sciences (2001) and the Takeru Higuchi Research Prize (2003) from the American Pharmaceutical Association; the Smissman-Bristol-Myers Squibb Award from the Medicinal Chemistry Division of the American Chemical Society (2003); PolyPops Foundation Award from the Society for Biomolecular Sciences (2007); and Honorary Doctorate Degrees from The Danish University of Pharmaceutical Sciences, Copenhagen, Denmark (2002), Katholieke University, Leuven, Belgium (2004) and Uppsala University, Uppsala, Sweden (2006).

Professor Borchardt is the author or co-author of more than 500 scientific publications and 460 abstracts. He is also the Editor of 10 books, and the Series Editor of "Pharmaceutical Biotechnology" (14 published volumes, Springer) and "Biotechnology: Pharmaceutical Aspects" (7 published volumes, AAPS Press/Springer).

Education

Ph.D. in Medicinal Chemistry, University of Kansas, Lawrence, KS
B.S. in Pharmacy, University of Wisconsin, Madison, WI

Research

Professor Borchardt’s interest in drug design has focused on the design and synthesis of inhibitors of an enzyme (S-adenosylhomocysteine hydrolase) that plays a key role in regulating biological methylation reactions, which are crucial for the replication of some viruses and parasites. 

Research Interests

  • The development of epithelial and endothelial cell culture systems for the study of drug transport and metabolism
  • The development of rational strategies (e.g. prodrugs) to improve the transport characteristics of peptides and peptidomimetics
  • The elucidation of the chemical pathways of protein and peptide degradation
  • The development of strategies to stabilize biomolecules in pharmaceutical formulations

Selected Publications

  1.  S. M. Kupchan, T. H. Yang, M. L. King and R. T. Borchardt, " Thalictrum Alkaloids, VIII.  The Isolation, Structural Elucidation and Synthesis of Dehydrothalcarpine", J. Org. Chem., 33, 1052-1055 (1968).

        2.  Ronald T. Borchardt, " A Stereochemical Approach to the Adrenergic System", Ph.D. Thesis, University of Kansas, 1970.

        3.  E. E. Smissman and R. T. Borchardt, "A Conformational Study of Catecholamine Receptor Sites.  V.  The Synthesis of dl-3-Amino-2-(3', 4'-dihydroxyphenyl)-trans-decalol Hydrochlorides", J. Med. Chem., 14, 377-382 (1971).

        4.  E. E. Smissman and R. T. Borchardt, "A Conformational Study of Catecholamine Receptor Sites.  VI.  The Synthesis of dl-3-Amino-2-(3', 4'-dihydroxyphenyl)-trans-decalin Hydrochlorides", J. Med. Chem., 14, 383-387 (1971).

        5.  E. E. Smissman and R. T. Borchardt, " Conformational Study of Catecholamine Receptor Sites.  VII.  Syntheses of erythro- and threo-2-Amino-3-(3', 4'-dihydroxyphenyl)-butane Hydrochlorides", J. Med. Chem., 14, 701-707 (1971).

        6.  E. E. Smissman, R. T. Borchardt and K. B. Schowen, "Conformational Aspects of Systems Related to Acetylcholine.  IV.  The Syntheses of the dl-2-Dimethylamino-trans-decalin Methiodides", J. Med. Chem., 15, 545-548 (1972).

        7.  R. T. Borchardt and L. A. Cohen, "Stereopopulation Control.  II.  Rate Enhancement of Intramolecular Nucleophilic Displacement", J. Amer. Chem. Soc., 94, 9166-9174 (1972).

        8.  R. T. Borchardt and L. A. Cohen, "Stereopopulation Control.  III.  Facilitation of      Intramolecular Conjugate Addition of the Carboxyl Group", J. Amer. Chem. Soc., 94, 9175-9182 (1972).

        9.  R. T. Borchardt, " Catechol-O-Methyltransferase.  I.  Kinetics of Tropolone Inhibition", J. Med. Chem., 16, 377-382 (1973).

       10.  R. T. Borchardt, "Catechol-O-Methyltransferase.  II.  In Vitro Inhibition by Substituted 8-Hydroxyquinolines",  J. Med. Chem., 16, 382-387 (1973).

    11.  R. T. Borchardt, "Catechol-O-Methyltransferase.  III.  Mechanism of Pyridoxal 5'-Phosphate Inhibition", J. Med. Chem., 16, 387-391 (1973).

    12.  R. T. Borchardt, "Catechol-O-Methyltranferase.  IV.  In Vitro  Inhibition by 3-Hydroxy-4-Pyridones and 3-Hydroxy-2-Pyridones", J. Med. Chem., 16, 581-583 (1973).

    13.  R. T. Borchardt and D. Thakker, "Affinity Labeling of Catechol-O-Methyltransferase", Biochem. Biophys. Res. Commun., 54, 1233-1239 (1973).

    14.    R. T. Borchardt and L. A. Cohen, "Stereopopulation Control.  IV.  Facilitation of Intramolecular Conjugate Addition of Solvated Hydroxyl Groups", J. Amer. Chem. Soc., 95, 8303-8313 (1973).

    15.  R. T. Borchardt and L. A. Cohen, "Stereopopulation Control.  V.  Facilitation of Intramolecular Conjugate Addition of an Aldehyde Hydrate and Hemiacetal", J. Amer. Chem. Soc., 95, 8313-8319 (1973).

    16.  R. T. Borchardt and L. A. Cohen, "Stereopopulation Control.  VI.  Conformational Selection of Alternative Oxidative Pathways", J. Amer. Chem. Soc., 95, 8319-8326 (1973).

    17.  C. R. Creveling, R. T. Borchardt, and C. Isersky, "Immunological Characterization of Catechol-O-Methyltransferase", in Frontiers in Catecholamine Research (E. Usdin and S. H. Snyder, Eds.), Pergamon Press, New York, p. 117-119 (1973).

    18.  R. T. Borchardt, "A Rapid Spectrophotometric Assay for Liver Catechol-O-Methyltransferase", Anal. Biochem., 58, 382-389 (1974).

    19.  R. T. Borchardt, C. F. Cheng, P. H. Cooke and C. R. Creveling, "Purification and Properties of Microsomal Catechol-O-Methyltransferase", Life Sciences, 14, 1089-1100 (1974).

    20.  R. T. Borchardt and P. E. Hanna, "Histamine-N-Methyltransferase:  Inhibition and Potentiation by trans and cis-1, 5-Diphenyl-3-dimethyl-aminopyrrolidine", J. Med. Chem., 17, 471-473 (1974).

    21.  R. T. Borchardt and Y. S. Wu, "Potential Inhibitors of S-Adenosylmethionine-Dependent Methyltransferases.  I.  Modification of the Amino Acid Portion of S-Adenosyl-

            homocysteine", J. Med. Chem., 17, 862-868 (1974).

    22.  R. T. Borchardt, J. A. Huber and Y. S. Wu, "Potential Inhibitors of S-Adenosylmethionine-Dependent Methyltransferases.  II.  Modification of the Base Portion of S-Adenosylhomocysteine", J. Med. Chem., 17, 868-873 (1974).

    23.  R. T. Borchardt, "Synthesis and Biological Activity of Analogs of S-Adenosylhomocysteine and Inhibitors of Methyltransferases", in The Biochemistry of S-Adenosylmethionine, (F. Solvatore, E. Borck, V. Zappia, H. G. Williams-Ashman, F. Schlenk, Eds.), Columbia University Press, New York, p. 151-170,  1977.

    24.  R. T. Borchardt, C. R. Creveling and C. Isersky, "Immunological Characterization of Catechol-O-Methyltransferase", Biochem. Pharmacol. Suppl., 23, 72 (1974).

    25.  R. T. Borchardt and J. A. Huber, "Catechol-O-Methyltransferase.  V.  Structure-Activity Relationships for Inhibition by Flavonoids", J. Med. Chem., 18, 120-122 (1975).

    26.  R. T. Borchardt and D. R. Thakker, "Catechol-O-Methyltransferase.  VI.  Affinity Labeling with N-Haloacetyl-3,5-Dimethoxy-4-Hydroxyphenylalkylamines", J. Med. Chem., 18, 152-158 (1975).

    27.  R. T. Borchardt and Y. S. Wu, "Potential Inhibitors of S-Adenosylmethionine-Dependent Methyltransferases.  III.  Modifications of the Sugar Portion of S-Adenosylmethionine", J. Med. Chem., 18, 300-304 (1975).

    28.  R. T. Borchardt, C. F. Cheng and D. R. Thakker, "Purification of Catechol-O-Methyltransferases by Affinity Chromatography", Biochem. Biophys. Res. Commun., 63, 69-77 (1975).

    29.  R. T. Borchardt, "Affinity Labeling of Catechol-O-Methyltransferase by the Oxidation Products of 6-Hydroxydopamine", Mol. Pharmacol., 11, 436-449 (1975).

    30.  R. T. Borchardt, "Inhibition of Indoleethylamine-N-Methyltransferase by Analogs of S-Adenosylhomocysteine", Biochem. Pharmacol., 24, 1542-1544 (1975).

    31.  R. T. Borchardt, G. L. Grunewald, J. M. Grindel and W. C. Vincek, "Importance of the Aromatic Ring in Adrenergic Amines.  Non-Aromatic Analogs of Phenylethanolamine as Substrates for Phenylethanolamine-N-Methyltransferase", Mol. Pharmacol., 11, 694 -699 (1975).

    32.  R. T. Borchardt and D. R. Thakker, "Affinity Labeling of Catechol-O-Methyltransferase by N-Haloacetyl Derivatives of 3, 5-Dimethoxy-4-Hydroxyphenylethylamine and 3, 4-Dimethoxy-5-Hydroxyphenylethylamine.  Kinetics of Inactivation", Biochemistry, 14, 4543-4551 (1975).

    33.  E. E. Smissman, J. R. Reid, D. A. Walsh and R. T. Borchardt, "Synthesis and Biological Activity of 2- and 4-Substituted-6,7-Dihydroxy-1,2,3,4-Tetrahydroisoquinoline", J. Med. Chem., 19, 127-131 (1976).

    34.  R. T. Borchardt, E. E. Smissman, D. Nerland and J. R. Reid, "Catechol-O-Methyltransferase.  7.  Affinity Labeling with the Oxidation Products of 6-Aminodopamine", J. Med. Chem., 19, 30-37 (1976).

    35.  R. T. Borchardt and Y. S. Wu, "S-Aristeromycinyl-L-Homocysteine--A Potent Inhibitor of S-Adenosylmethionine-Dependent Transmethylations", J. Med. Chem., 19, 197-198 (1976).

    36.  R. T. Borchardt, "Catechol-O-Methyltransferase:  A Model to Study the Mechanism of 6-Hydroxydopamine Interaction with Proteins", in Chemical Tools in Catecholamine Research (G. Jonsson, T. Malmfors and C. Sachs, Eds.), North Holland Publishing Company, Amsterdam, p. 33 -40, 1975.

    37.  R. T. Borchardt, J. A. Huber and Y. S. Wu, "A Convenient Preparation of S-Adenosylhomocysteine and Related Compounds", J. Org. Chem., 41, 565-567 (1976).

    38.  R. T. Borchardt, D. R. Thakker, W. D. Warner, D. M. Mirth and J. N. Sane, "Catechol-O-Methyltransferase.  8.  Structure-Activity Relationship for Inhibition by 8-Hydroxyquinoline", J. Med. Chem., 19, 558-560 (1976).

    39.  R. T. Borchardt, "New Approaches to Controlling the Activity of Phenylethanolamine-N-Methyltransferase in Stress", in Catecholamines and Stress (E. Usdin, R. Kvetnansky and I. J. Kopin, Eds.), Pergamon Press, Oxford, p. 313-319,  1976.

    40.  M. R. Hegazi, R. T. Borchardt and R. L. Schowen, "An SN2-Like Transition State for Methyl Transfer Catalyzed by Catechol-O-Methyltransferase", J. Amer. Chem. Soc., 98, 3048-3049 (1976).

    41.  R. T. Borchardt, Y. S. Wu and J. A. Huber, "Potential Inhibitors of S-Adenosylmethionine-Dependent Methyltransferases.  IV.  Further Modifications of the Amino Acid and Base Portions of S-Adenosylhomocysteine", J. Med. Chem., 19, 1094-1099 (1976).

    42.  R. T. Borchardt and Y. S. Wu, "Potential Inhibitors of S-Adenosylmethionine-Dependent Methyltransferases.  V.  The Role of the Asymmetric Sulfonium Pole in Enzymatic Binding of S-Adenosylmethionine", J. Med. Chem., 19, 1099-1103 (1976).

    43.  R. T. Borchardt, J. A. Huber, A. F. Wycpalek and Y. S. Wu, "Potential Inhibitors of S-Adenosylmethionine-Dependent Methyltransferases.  VI.  Structural Modifications of S-Adenosylmethionine", J. Med. Chem., 19, 1104 -1110 (1976).

    44.  R. T. Borchardt, D. R. Thakker and J. R. Reid, "Catechol-O-Methyltransferase.  9.  Mechanism of Inactivation by 6-Hydroxydopamine", J. Med. Chem., 19, 1201-1209 (1976).

    45.  R. T. Borchardt and D. R. Thakker, "Evidence for Sulfhydryl Groups at the Active Site of Catechol-O-Methyltransferase", Biochim. Biophys. Acta, 445, 598-609 (1976).

    46.  R. T. Borchardt and D. R. Thakker, "Affinity Labeling of Catechol-O-Methyltransferase Using N-Haloacetyl Derivatives of 3,5-Dimethoxy-4-Hydroxyphenylethylamine and 3,4-Dimethoxy-5-Hydroxyphenylethylamine", in Methods in Enzymology-AffinityLabeling (W. B. Jocoby and M. Wilcheck, Eds.), Academic Press, New York, Vol. 46, p. 554-561, 1977.

    47.  R. T. Borchardt, W. C. Vincek and G. L. Grunewald, "A Liquid Chromatographic Assay for Phenylethanolamine N-Methyltransferase", Anal. Biochem., 82, 149-151 (1977).

    48.  R. T. Borchardt, S. K. Burgess, J. R. Reid, Y. O. Liang and R. N. Adams, "Effects of 2- and/or 5-Methylated Analogs of 6-Hydroxydopamine of Noradrenergic and Dopaminergic Neurons", Mol. Pharmacol., 13, 805-818 (1977).

    49.  R. T. Borchardt, C. Pugh and H. O. Stone, "Inhibition of Newcastle Disease Virion m-RNA (guanine 7-)methyltransferase by Analogs of S-Adenosylhomocysteine", Biochemistry, 16, 3928-3932 (1977).

    50.  R. T. Borchardt, "Chemical Probes of the Active Site of Catechol-O-Methyltransferase", in Biochemistry and Function of Monoamine Enzymes (E. Usdin and N. Weiner, Eds.), Marcel Dekker, New York, p. 707-726, 1977.

    51.  R. T. Borchardt and C. S. Schasteen, "Phenol-Sulfotransferase Inactivation by 2,3-Butanedione and Phenylglyoxal:  Evidence for an Active Site Arginyl Residue", Biochem. Biophys. Res. Commun., 78, 1067-1073 (1977).

    52.  R. T. Borchardt, Y. S. Wu and B. S. Wu, "S-Adenosyl-L-Homocysteine Dialdehyde:  An Affinity Labeling Reagent for Histamine-N-Methyltransferase", Biochem. Biophys. Res. Commun., 78, 1025-1033 (1977).

    53.  R. T. Borchardt and C. F. Cheng, "Purification and Characterization of Rat Heart and Brain Catechol-O-Methyltransferase", Biochim. Biophys. Acta, 522, 49-62 (1978).

    54.  R. T. Borchardt, M. F. Hegazi and R. L. Schowen, "The Determination of the O-Methylated Metabolites of Catecholamines Using High Performance Liquid Chromatography and Electrochemical Detection", J. Chromatography,152, 25-259 (1978). 

    55.  R. T. Borchardt, S. E. Wu and C. S. Schasteen, "Adenosine 5'-Diphosphate Dialdehyde:  An Affinity Labeling Reagent for Phenol-sulfotransferase", Biochem. Biophys. Res. Commun., 81, 841-849 (1978).

    56.  R. T. Borchardt and C. F. Cheng, "Purification and Characterization of Rat Liver Thiol-S-Methyltransferase", Biochim. Biophys. Acta, 522, 340-353 (1978).

    57.  R. T. Borchardt, Y. S. Wu and B. S. Wu, "Mechanism of Inhibition of Pineal Hydroxyindole-O-Methyltransferase by Pyridoxal 5'-Phosphate", Biochem. Pharmacol., 27, 120-122 (1978).

    58.  R. T. Borchardt, C. Pugh and H. O. Stone, "Simultaneous Assays for m-RNA(Guanine-7-) Methyltransferase and m-RNA(Nucleoside-2'-)Methyltransferase", Anal. Biochem., 88, 502-512 (1978).

    59.  P. S. Leboy, F. Steiner, S. Henry, J. M. Glick and R. T. Borchardt, "S-Adenosylhomocysteine Analogues as Inhibitors of Specific t-RNA Methylations", Biochim. Biophys. Acta, 520, 153-163 (1978).

    60.  R. T. Borchardt, C. Pugh and H. O. Stone, "Sinefungin:  A Potent Inhibitor of Virion m-RNA(Guanine-7-)Methyltransferase and m-RNA(Nucleoside-2'-)Methyltransferase and Viral Multiplication", J. Biol. Chem., 253, 4075-4077 (1978).

     61. R. T. Borchardt, J. Olsen, L. Eiden, R. L. Schowen and C. O. Rutledge, "The Isolation and    Characteriaztion of the Methyl Acceptor Proteins from Adrenal Chromaffin Granules", Biochem. Biophys. Res. Commun., 83, 970-976 (1978).

    62.  R. T. Borchardt, J. A. Huber and Y. S. Wu, "An Improved Synthesis of S-Adenosylhomocysteine", in Nucleic Acid Chemistry; Improved and New Synthetic Procedures:  Methods and Techniques (L. B. Townsend and R. S. Tipson, Eds.), Wiley-Interscience, New York, Part II, p. 541-545, 1978.

    63.  R. T. Borchardt, M. F. Hegazi, S. Osaki and R. L. Schowen, "S-Adenosyl-L-Methionine-CD­3 and S-Adenosyl-L-Methionine-13CH3", in Nucleic Acid Chemistry; Improved and New Synthetic Procedures:  Methods and Techniques (L. B. Townsend and R. S. Tipson, Eds.), Wiley-Interscience, New York, Part II, p. 889-894, 1978.

    64.  R. T. Borchardt, "The Mechanism of Alkaline Hydrolysis of S-Adenosyl-L-Methionine and Related Sulfonium Nucleosides", J. Amer. Chem. Soc., 101, 458-463 (1979).

    65.  R. T. Borchardt, Y. S. Wu and B. S. Wu, "Affininty Labeling of Histamine-N-Methyltransferase by 2',3'-Dialdehyde Derivatives of S-Adenosylhomocysteine and S-Adenosylmethionine.  Kinetics of Inactivation", Biochemistry, 17, 4145-4153 (1978).

    66.  R. T. Borchardt, Y. S. Wu and B. S. Wu, "Potential Inhibitors of S-Adenosylmethionine-Dependent Methyltransferases.  7.  Role of the Ribosyl Moiety in Enzymatic Binding of S-Adenosylhomocysteine and S-Adenosylmethionine", J. Med. Chem., 21, 1307-1310 (1978).

    67.  R. E. Tessel, L. E. Kennedy, S. K. Burgess and R. T. Borchardt, "Epinephrine in Rat Hypothalamus:  Antagonism of Desmethylimipramine of 6-Hydroxydopamine-Induced Depletion", Brain Research, 153, 615-617 (1978).

    68.  M. F. Hegazi, R. T. Borchardt and R. L. Schowen, "alpha-Deuterium and Carbon-13 Isotope Effects for Methyl Transfer Catalyzed by Catechol-O-Methyltransferase: SN2-like Transition State", J. Amer. Chem. Soc., 101, 4359-4365 (1979).

    69.  G. L. Grunewald, W. C. Vincek, D. P. Davis and R. T. Borchardt, "Some New Inhibitors of Epinephrine Biosynthesis", in Catecholamines:  Basic and Clinical Frontiers (E. Usdin, I. J. Kopin and J. Barchas, Eds.), Pergamon Press, New York, Vol. 1, p. 189-191, 1979.

    70.  R. T. Borchardt, J. Olsen. J. Eiden, R. L. Schowen and C. O. Rutledge, "Isolation and Characterization of Methyl Acceptor Protein from Adrenal Chromaffin Granules", in Catecholamines:  Basic and Clinical Frontiers (E. Usdin, I. J. Kopin and J. Barchas, Eds.), Pergamon Press, New York, Vol. 1, p. 250-252, 1979.

    71.  R. T. Borchardt and C. S. G. Pugh, "Analogues of S-Adenosyl-L-Homocysteine as Inhibitors of Viral mRNA Methyltransferases", in  Transmethylation (E. Usdin, R. T. Borchardt and C. R. Creveling, Eds.), Elsevier North-Holland, New York, p. 197-206, 1979.

    72.  L. Eiden, R. T. Borchardt and C. O. Rutledge, "Protein Carboxymethylation in Neurosecretary Process", in Transmethylation (E. Usdin, R. T. Borchardt and C. R. Creveling, Eds.), Elsevier North-Holland, New York, p. 539-546, 1979.

    73.  J. Olsen, Y. S. Wu, R. T. Borchardt, and R. L. Schowen, "Transition-State Structure and Catalytic Power in Methyl Transfer," in Transmethylation (E. Usdin, R. T. Borchardt and C. R. Creveling, Eds.), Elsevier-North Holland, New York, p. 127-133, 1979.

    74.  R. T. Borchardt, L. E. Eiden, B. S. Wu and C. O. Rutledge, "Sinefungin, a Potent Inhibitor of S-Adenosylmethionine:  Protein O-Methyltransferase", Biochem. Biophys. Res. Commun., 89, 919-924 (1979).

    75.  R. T. Borchardt, "S-Adenosyl-L-Methionine-Dependent Macromolecule Methyltransferases:  Potential Targets for the Design of Chemotherapeutic Agents", J. Med. Chem., 23, 347-357 (1980).

    76.  R. T. Borchardt, "N- and O-Methylation" in Enzymatic Basis of Detoxification (W. B. Jakoby, Ed.), Academic Press, New York, Vol. II, p. 43-62, 1980.

    77.  H. Hibasami, R. T. Borchardt, S. Y. Chen, J. K. Coward and A. E. Pegg, "Studies of Inhibition of Rat Spermidine and Spermine Synthesis", Biochem. J., 187, 419-428 (1980).

    78.  A. W. Wertheimer, S. Y. Chen, R. T. Borchardt and Y. Furuichi, "S-Adenosylmethionine and its Analogs:  Structrual Features Correlated with Synthesis and Methylation of mRNA's of Cytoplasmic Polyhedrosis Virus", J. Biol. Chem., 255, 5924-5930 (1980).

    79.  W. C. Vincek, C. Aldrich, R. T. Borchardt and G. L. Grunewald, "Non-Aromatic Analogs of Phenylethanolamine as Inhibitors of Phenylethanolamine-N-Methyltransferase:  The Role of Hydrophobic Interaction.  Importance of the Aromatic Ring in Adrenergic Amines, " J. Med. Chem., 24, 7-12 (1981).

    80.  D. Davis, R. T. Borchardt, and G. L. Grunewald, "Non-Aromatic Analogs of Phenylethanolamine and Inhibitors of Phenylethanolamine-N-Methyltransferase:  The Role of  π Electronic Interactions.  Importance of Aromatic Ring in Adrenergic Amines", J. Med. Chem., 24, 12-16 (1981).

    81.  A. E. Pegg, R. T. Borchardt and J. K. Coward, "Effects of Inhibitors of Spermidine and Spermine Synthesis on Polyamine Levels and Growth of Transformed Mouse Fibroblasts", Biochem. J., 194, 79-89 (1981).

    82.  R. T. Borchardt, "Catechol-O-Methyltransferase:  Assay, Purification and Properties", in Methods in Enzymology, Detoxification and Drug Metabolism:  Conjugation and Related Systems (W. B. Jakoby, Ed.), Academic Press, New York, Vol. 77, 267-272, 1981.

    83.  A. Baranczyk-Kuzma, R. T. Borchardt, C. S. Schasteen and C. Pinnick, "Phenol Sulfotransferase:  Purification and Characterization of the Rat Enzyme", in Phenol Sulfotransferase in Mental Health Research (E. Usdin and M. Sandler, Eds.), Macmillan Publishers, London, p. 55-73, 1981.

    84.  A. Baranczyk-Kuzma, R. T. Borchardt, C. S. Schasteen and C. Pinnick, "Phenol Sulfotransferase:  Purification and Characterization of the Rat Liver, Kidney and Brain Enzymes", Psychopharmacology Bulletin, 17, 50-52 (1981).

    85.  R. T. Borchardt and J. A. Huber, "3-Substituted-4-Methoxy-5-Hydroxybenzaldehydes and Benzoic Acids as Inhibitors of Catechol-O-Methyltransferase", in Function and Regulation of Monoamine Enzymes - Basic and Clinical Aspects (E. Usdin, N. Weiner, M. B. H. Youdin, Eds.), Macmillan, London, p. 657-664,  1981.

    86.  G. L. Grunewald, R. T. Borchardt, M. F. Rafferty and P. Krass, "Conformational Preferences of Amphetamine Analogues for Inhibition of Phenylethanolamine N-Methyltransferase.  Conformationally Defined Adrenergic Agents 5", Mol. Pharmacol., 20, 377-381 (1981).

    87.  L. E. Eiden, R. T. Borchardt and C. O. Rutledge, "Protein Carboxymethylation in the Rat Hypothalamus", J. Neurochem., 38, 631-637 (1982).

    88.  R. T. Borchardt and A. K. Sinhababu, "An Efficient Synthesis of 3,5-Dihydroxy-4-Methylbenzoic Acid", J. Org. Chem., 24, 5021-5022 (1981).

    89.  R. T. Borchardt and J. A. Huber, "Catechol-O-Methyltransferase 10.  3-Substituted-4-Methoxy-5-Hydroxybenzaldehydes and Benzoic Acids as Inhibitors", J. Med. Chem., 25, 258-263 (1982).

    90.  R. T. Borchardt and J. A. Huber, "Catechol-O-Methyltransferase 11.  Affinity Labeling with 3-Mercapto-4-Methoxy-5-Hydroxybenzoic Acid", J. Med. Chem., 25, 321-323 (1982).

    91.  R. T. Borchardt and P. Bhatia, "Catechol-O-Methyltransferase 12.  Affinity Labeling with the Oxidation Products of 5,6-Dihydroxyindole", J. Med. Chem., 25, 263-271 (1982).

    92.  J. A. Yoffe and R. T. Borchardt, "Characterization of Serotonin Uptake in Cultured Pheochromocytoma Cells.  Comparison with Norepinephrine Uptake", Mol. Pharmacol., 21, 362-367 (1982).

    93.  J. A. Yoffe and R. T. Borchardt, "Characterization of Serotonin Uptake in Cultured Neuroblastoma Cells.  Difference Between Differentiated and Nondifferentiated Cells", Mol. Pharmacol., 21, 368-373 (1982).

    94.  R. T. Borchardt, D. Kuonen, J. A. Huber and A. Moorman, "Inhibition of Calf Thymus and Rat Hypothalamic Synaptosomal Protein Carboxymethyltransferase by analogues of S-Adenosylhomocysteine", Mol. Pharmacol., 21, 181-186 (1982).

    95.  C. S. G. Pugh and R. T. Borchardt, "Effects of S-Adenosylhomocysteine Analogues on Vaccinia Virion RNA Synthesis and Posttranscriptional Modification", Biochemistry, 21, 1535-1541 (1982). 

    96.  R. T. Borchardt, A. Baranczyk-Kuzma, C. S. Schasteen, Su-Er Wu, and C. Pinnick, "Purification and Characterization of a Rat Liver Isozyme", in Sulfate Metabolism and Sulfate Conjugation, (G. J. Mulder, F. Caldwell, G. M. VanKemperal, R. J. Vork, Eds.), Taylor and Frances, London, p. 29-35 (1982).

    97.  N. Y. Liang, R. E. Tessel,  G. L. Grunewald and R. T. Borchardt, "The Use of Phenylethanolamine N-Methyltransferase Inhibitors in Elucidating the Role of Brain Epinephrine in the Control of Cardiovascular Function", in The Biochemistry of S-Adenosylmethionine and Related Compounds  (R. T. Borchardt, C. R. Creveling and E. Usdin, Eds.), Macmillan, London, p. 457-460 (1982).

    98.  R. T. Borchardt, U. G. Patel and Ronnda Bartel, "2'-O-[(R)-Formyl-(adenin 9yl)methyl]-(S)-glyceraldehyde:  A Potent Inhibitor of S-Adenosylhomocysteine Hydrolase", in The Biochemistry of S-Adenosylmethionine and Related Compounds    (R. T. Borchardt, C. R. Creveling and E. Usdin, Eds.), Macmillan, London, p. 645-652 (1982).

    99.  M. Frana, R. T. Borchardt and H. O. Stone, "Inhibition of Rous Sarcoma Virus Mediated Cellular Transformation by Analogues of S-Adenosyl-L-Homocysteine", in The Biochemistry of S-Adenosylmethionine and Related Compounds  (R. T. Borchardt, C. R. Creveling and E. Usdin, Eds.), Macmillan, London, p. 657-666 (1982).

   100. R. T. Borchardt and J. E. Simmons, "General Method for the Preparation of a and/or b Deuterium-Labelled 6-Hydroxydopamine Derivatives", J. Labelled Compds. Radiopharm., 19, 433-445 (1982).

101. J. R. Yoffe and R. T. Borchardt, "Effects of Ascorbic Acid on the Uptake of Serotonin into Differentiated Neuroblastoma Cells", Life Sciences, 31,  489-493 (1982).

102.  R. T. Borchardt and C. S. Schasteen, "Phenol Sulfotransferase: I. Purification of the Rat Liver Enzyme by Affinity Chromatography", Biochim. Biophys. Acta708, 272-279 (1982).

103.  R. T. Borchardt, C. S. Schasteen and Su-Er Wu, "Phenol Sulfotransferase: II. Inactivation by 2,3-Butanedione, Phenylglyoxal, N-Ethylmaleimide and Nucleotide Dialdehydes", Biochim. Biophys. Acta708, 280-293 (1982).

104.  N. Y. Liang, R. E. Tessel, G. L. Grunewald and R. T. Borchardt, "Inhibitors of Phenethanolamine N-Methyltransferase. 1. Effects of 2-Cyclooctyl-2-Hydroxyethylamine on Rat Brain Catecholamine Content and Blood Pressure", J. Pharmacol. Exptl. Therap.223, 375-381 (1982).

105.  N. Y. Liang, R. E. Tessel, G. L. Grunewald and R. T. Borchardt, "Inhibitors of Phenethanolamine N-Methyltransferase. 2. Effects on Rat Brain and Adrenal Catecholamine Content and Blood Pressure.  Comparison of Nonaromatic Analogues of Phenylethanolamine, SKF64139 and 3,4-Dichlorobenzylamine", J. Pharmacol. Exptl. Therap., 223, 382-387 (1982).

106.  M. F. Rafferty, D. S. Wilson, J. A. Monn, P. Krass, R. T. Borchardt and G. L. Grunewald, "Comparisons of Norepinephrine N-Methyltransferase for Aromatic Versus Nonaromatic Substrate and Inhibitors.  The Importance of the Aromatic Ring in Adrenergic Amines. 7.", J. Med. Chem.25, 1198-1204 (1982).

107.  M. F. Rafferty, P. Krass, R. T. Borchardt and G. L. Grunewald, "2-(Aminomethyl)-trans-2-decalols as Inhibitors of Norepinephrine N-Methyltransferase.  Importance of the Aromatic Ring in Adrenergic Amines. 8.", J. Med. Chem., 25, 1250-1252 (1982).

108.  G. L. Grunewald, J. Monn, M. F. Rafferty, P. Krass and R. T. Borchardt, "Probes of the Active Site of Norepinephrine N-Methyltransferase: The Effect of Hydrophobic and Hydrophilic Interactions on Side Chain Binding of Amphetamine and a-Methylbenzylamine", J. Med. Chem., 25, 1248-1250 (1982).

109.  M. F. Rafferty, G. L. Grunewald and R. T. Borchardt, "Probes of the Active Site of Norepinephrine N-Methyltransferase: Directional Probes of the Hydrophobic Component of the Aromatic Ring Binding Site", J. Med. Chem., 25, 1204-1208 (1982).

110.  N. Y. Liang, G. L. Grunewald and R. T. Borchardt, "Effect of Inhibitors of Phenylethanolamine N-Methyltransferase on Rat Brain Epinephrine Levels and Body Temperature", Res. Commun. Chem. Pathol. Pharmacol., 37, 445-452 (1982).

111.  A. R. Moorman and R. T. Borchardt, "Synthesis of Methyl 5-O-Acetyl-7-Deoxy-2,3-O-Isopropylidene Heptofuranoside-6-ulose", Carbohydrate Res., 119, 269-272 (1983).

112.  A. R. Moorman, R. T. Borchardt and T. Martin, "Addition of 1-Nitroalkanes to 2,3-O-Isopropylidene-b-D-Ribopentodialdo-1,4-Furanoside and N6 -Benzoyl-2',3'-O-Isopropylideneadenosine 5'-Aldehyde", Carbohydrate Res., 113, 233-239 (1983).

113.  A. Baranczyk-Kuzma, R. T. Borchardt and C. Pinnick, "An Ecteola-Cellulose Chromatography Assay for 3'-Phosphoadenosine 5'-Phosphosulfate: Phenol Sulfotransferase (EC 2.8.2.1)", Anal. Biochem., 130, 334-338 (1983).

114.  C. W. Bradberry, R. T. Borchardt and C. J. Decedue, "Immobilization of Ascorbic Acid Oxidase", FEBS Letters146, 348-352 (1982).

115.  B. Matuszewska and R. T. Borchardt, "Guinea Pig Brain Histamine N-Methyltransferase: Purification and Partial Characterization", J. Neurochem., 41, 113-118 (1983).

116.  J. Simmons and R. T. Borchardt, "Regioselective Synthesis of Deuterium Labelled 6-Hydroxydopamines", J. Labelled Compds. Radiopharm., 20, 325-338 (1983).

117.  A. Sinhababu and R. T. Borchardt, "Silica Gel-Assisted Reductive Cyclization of Dinitrostyrenes to Indoles", J. Org. Chem., 48, 3347-3349 (1983).

118.  A. Sinhababu and R. T. Borchardt, "A General Method for the Synthesis of Phthalaldehydic Acids and Phthalides from ortho-Bromobenzaldehydes via ortho-Lithiated Aminoalkoxides", J. Org. Chem., 48, 2356-2360 (1983).

119.  A. Sinhababu and R. T. Borchardt, "An Efficient Method for Conversion of Phenolic Mannich Bases to C-Methylated Phenols: Synthesis of 3,6-Dimethylcatechol", Synth. Commun.12, 983-988 (1982).

120.  A. Sinhababu and R. T. Borchardt, "Selective Ring C-Methylaton of Hydroxybenzaldehydes via Their Mannich Bases", Synth. Commun.13, 677-683 (1983).

121.  A. Sinhababu and R. T. Borchardt, "Silica Gel-Assisted Reduction of Nitrostyrenes to Nitroalkanes with Sodium Borohydride", Tetrahedron Letters24, 227-230 (1983).

122.  A. Sinhababu and R. T. Borchardt, "Silica Gel-Assisted Reduction of Nitrostyrenes to 2-Aryl-2-[3H]-Nitroethanes with Sodium Borodeuteride", J. Labelled Compds. Radiopharm., 20,1027-1033 (1983).

123.  Su-Er Wu, W. P. Huskey, R. T. Borchardt and R. L. Schowen, "The Chiral Instability at Sulfur of S-Adenosylmethionine", Biochemistry22, 2828-2832 (1983).

124.  A. Sinhababu and R. T. Borchardt, "Aromatic Hydroxylation.  Hydroxybenzaldehydes from Bromobenzaldehydes via Reaction of in situ Generated, Lithiated a-Morpholinobenzyl Alkoxides with Nitrobenzene", J. Org. Chem., 48, 1941-1944 (1983).

125.  R. Bartel and R. T. Borchardt, "Effects of Adenosine Dialdehyde on S-Adenosylhomocysteine Hydrolase and S-Adenosylmethionine-Dependent Transmethylations in Mouse L-Cells", Mol. Pharmacol.25, 418-424 (1984).

126.  R. T. Borchardt, B. T. Keller and U. Patel-Thombre, "Neplanocin A.  A Potent Inhibitor of Cell S-Adenosylhomocysteine Hydrolase and Vaccinia Virus Multiplication in Mouse L-929 Cells", J. Biol. Chem., 259, 4353-4358 (1984).

127.  A. M. Trammel, J. E. Simmons and R. T. Borchardt, "An Efficient In Vitro Assay for Acetylcholinesterase Regenerators Using Immobilized Enzyme", Pharmaceutical Res., 1, 115-120 (1984).

128.  B. T. Keller and R. T. Borchardt, "Metabolic Conversion of Neplanocin A to S-Neplanocylmethionine by Mouse L-929 Cells", Biochem. Biophys. Res. Commun.120, 131-137 (1984).

129.  N.Y. Liang, C. A. Burrichter and R. T. Borchardt, "The Role of Central Epinephrine Neurons in Regulation of Serum Corticosterone Levels.  In Stress: The Role of Catecholamines and Other Neurotransmitters (E. Usdin, R. Kvetnansky and J. Axelrod, Eds.), Gordon and Breach Science Publishers, New York, p. 243-248, 1984.

130.  Su-Er Wu, W. P. Huskey, R. T. Borchardt and R. L. Schowen, "Different Isotope Effects of Parallel Pathways of Enzyme-Catalyzed Transmethylation", J. Amer. Chem. Soc.106, 5762-5763 (1984).

131.  N. Y. Liang, A. Chandra, R. E. Tessel, G. Grunewald and R. T. Borchardt, "Effects of Phenylethanolamine-N-Methyltransferase (PNMT) Inhibitors on Blood Pressure in DOCA Salt Hypertensive Rats", Res. Commun. Chem., Pathol. Pharmacol.46, 319-330 (1984).

132.  U. G. Patel and R. T. Borchardt, "Adenine Nucleoside 2',3'-Dialdehydes: Potent Inhibitors of Bovine Liver S-Adenosylhomocysteine Hydrolase", Biochemistry24, 1130-1136 (1985).

133.  D. M. Houston, E. K. Dolence, B. T. Keller, U. Patel-Thombre and R. T. Borchardt, "Potential Inhibitors of S-Adenosylmethionine-Dependent Methyltransferases. 8.  Molecular Dissections of Carbocyclic 3-Deaza-adenosine as Inhibitors of S-Adenosylhomocysteine Hydrolase", J. Med. Chem., 28, 467-471 (1985).

134.  D. M. Houston, E. K. Dolence, B. Keller, U. Patel-Thombre and R. T. Borchardt, "Potential Inhibitors of S-Adenosylmethionine-Dependent Methyltransferases. 9.  2',3'-Dialdehyde Derivatives of Carbocyclic Purine Nucleosides as Inhibitors of S-Adenosylhomocysteine Hydrolase", J. Med. Chem., 28, 471-477 (1985).

135.  D. M. Houston, B. Matuszewski and R. T. Borchardt, "Potential Inhibitors of S-Adenosylmethionine-Dependent Methyltransferases. 10. Base and Sugar Modified Analogs of S-Arisotermycinylhomocysteine", J. Med. Chem., 28, 478-482 (1985).

136.  R. T. Borchardt and B. Matuszewska, "S-Adenosylmethionine-Dependent Transmethylaton of Histamine: Purification and Partial Characterization of Guinea Pig and Rat Kidney Histamine N-Methyltransferase" in Frontiers in Histamine Research (C. R. Ganellin and J. C. Schwartz, Eds.), Pergamon Press, New York, p. 163-172, 1985.

137.  N. Y. Liang, J. A. Hower and R. T. Borchardt, "Release of Endogenous Brain Epinephrine by the Calcium-Ionophores X537A and A23187", Brain Res.341, 297-302 (1985).

138.  A. K. Sinhababu and R. T. Borchardt, "Efficient Synthesis of Deuterium Labelled Epinines", J. Labelled Compds. Radiopharm., 22, 767-774 (1985).

139.  A. K. Sinhababu, A. K. Ghosh and R. T. Borchardt, "Molecular Mechanism of Action of 5,6-Dihydroxytryptamine.  Synthesis and Biological Evaluation of 4-Methyl-, 7-Methyl- and 4,7-Dimethyl-5,6-Dihydroxytryptamines", J. Med. Chem.28, 1273-1279 (1985).

140.  A. K. Sinhababu and R. T. Borchardt, "Mechanism and Products of Autoxidation of 5,7-Dihydroxytryptamine", J. Amer. Chem. Soc.107, 7618-7627 (1985).

141.  R. Bartel and R. T. Borchardt, "Quantitation of S-Adenosylhomocysteine Hydrolase in Mouse L-929 Cells Using the Inhibitor Neplanocin A", Anal. Biochem.149, 191-196 (1985).

142.  B. T. Keller, R. S. Clark, A. E. Pegg and R. T. Borchardt, "Purification and Characterization of Some Metabolic Effects of S-Neplanocylmethionine", Mol. Pharmacol., 28, 364-370 (1985).

143.  I. Osiecka, R. T. Borchardt, J. A. Fix, C. A. Gardner and P. A. Porter, "In Vitro Drug Absorption Models.  I.  Brush Border Membrane Vesicles, Isolated Mucosal Cells and Everted Intestinal Rings: Characterization and Salciylate Accumulation", Pharmaceutical Res., 2, 284-293 (1985).

144.  P. A. Porter, I. Osiecka, R. T. Borchardt, J. A. Fix, L. Frost and C. A. Gardner, "In Vitro Drug Absorption Models. II.  Salicylate, Cefoxitin, a-Methyldopa and Theophylline Uptake in Cells and Rings: Correlation with In Vivo Bioavailability", PharmaceuticalRes.2, 293-298 (1985).

145.  A. Sinhababu , R. L. Bartel, N. Pochopin and R. T. Borchardt, "Mechanism of Action of S-Adenosyl-L-homocysteine Hydrolase.  Measurement of Kinetic Isotope Effects Using Adenosine 3'-d and S-Adenosyl-L-homocysteine 3'-d as Substrates", J. Amer Chem. Soc.107, 7628-7632 (1985).

146.  A. Baranczyk-Kuzma, R. T. Borchardt and C. L. Pinnick, "Phenol Sulfotransferase: Purification and Characterization of the Rat Kidney and Stomach Enzymes", Acta Biochimica Polonica32, 335-45 (1985).

147.  N. Y. Liang C. A. Burrichter, J. L. Vooght and R. T. Borchardt, "The Role of Central Epinephrine Neurons in the Regulation of Serum Prolactin and Leuteinizing Hormone Release in Female Rats", Res. Commun. Chem. Pathol. Pharmacol.48, 459-462 (1985).

148.  N. Y. Liang, J. A. Hower and R. T. Borchardt, "Effects of Phenylethanolamine-N-Methyltransferase Inhibitors on Uptake and Release of Norepinephrine and Dopamine from Rat Brain", Res. Commun. Chem. Pathol. Pharmacol.49, 467-470 (1985).

149.  B. Matuszewska and R. T. Borchardt, "Rat Kidney Histamine N-Methyltransferase: Purification and Characterization", Preparative Biochem., 14, 145-157 (1985).

150.  K. L. Audus and R. T. Borchardt, "Characterization of an InVitro Blood Brain Barrier Model System for Studying Drug Transport and Metabolism", Pharmaceutical Res., 3, 81-88 (1986).

151.  A. R. Moorman and R. T. Borchardt, "Synthesis of Methyl 7-Alkyl-6,7-Tetrahydro-6,7-talo-didedoxy-2,3-O-Isopropylidine-a-L- and b-D-allo-Hepto-Furanosides", in Nucleic Acid Chemistry: Improved and New Synthetic Procedures, Methods and Techniqjues in Nucleic Acid Chemistry, (L.B. Townsend and R. S. Tipson, Eds.), John Wiley & Sons, Inc., New York, Vol. 3, p. 38-42, 1986.

152.  B. T. Keller and R. T. Borchardt, "Metabolism and Mechanism of Action of Neplanocin A: A Potent Inhibitor of S-Adenosylhomocysteine Hydrolase" in Biological Methylation and Drug Design - Experimental and Clinical Roles of S-Adenosylmethionine (R. T. Borchardt, C. R. Creveling and P. M. Ueland, Eds.), Humana Press, Clifton, NJ, p. 385-396, 1986.

153.  A. Baranczyk-Kuzma, K. L. Audus and R. T. Borchardt, "Catecholamine-Metabolizing Enzymes of Bovine Brain Microvessel Endothelial Cell Monolayers", J. Neurochem.46, 1956-1960 (1986).

154.  K. L. Audus and R. T. Borchardt, "Characteristics of the Large Neutral Amino Acid Transport System of Bovine Brain Microvessel Endothelial Cell Monolayers", J. Neurochem., 47, 484-488 (1986).

155.  S. Rim, K. L. Audus and R. T. Borchardt, "Relationship of Octanol/Buffer and Octanol/Water Partition Coefficients to Transcellular Diffusion Across Brain Microvessel Endothelial Cell Monolayers", Int. J. Pharmaceutics32, 79-84 (1986).

156.  K. L. Audus and R. T. Borchardt, "Carrier-Mediated and Receptor-Mediated Transport Across the Endothelial Cells of the Vasculature" in Bioreversible Carriers in Drug Design: Theory and Applications (E. B. Roche, Ed.), Pergamon Press, New York, p. 226-242, 1987.

157.  R. T. Borchardt, "Endothelial Cells of the Vasculatuare: A Significant Barrier to Effective Drug Delivery", Proceedings of the International Symposium for Controlled Release of Bioactive Material14, 4-5 (1987).

158.  B. T. Keller and R. T. Borchardt, "Adenosine Dialdehyde: A Potent Inhibitor of Vaccinia Virus Multiplication in Mouse L-929 Cells", Mol. Pharmacol., 31, 485-492 (1987).

159.  I. Osiecka, M. Cortese, P. A. Porter, R. T. Borchardt, J. A. Fix and C. R. Gardner, "Intestinal Absorption of a-Methyldopa: In VitroMechanistic Studies in Rat Small Intestinal Segments", J. Pharmacol. Exptl. Therap., 242, 443-449 (1987).

160.  E. W. Fisher, C. J. Decedue, B. T. Keller and R. T. Borchardt, "Neplanocin A Inhibition of S-Adenosylhomocysteine Hydrolase in Alcaligenes Faecalis Has No Effect on Growth of the Microorganism", J. Antibiotics40, 873-881 (1987).

161.  V. Ramakrishnan and R. T. Borchardt, "Adenosine Dialdehyde and Neplanocin A: Potent Inhibitors of S-Adenosylhomocysteine Hydrolase in Neuroblastoma N-2a Cells", Neurochemistry International, 10, 423-431 (1987).

162.  B. Matuszewska and R. T. Borchardt, "Inhibition of S-Adenosylhomocysteine Hydrolase from Alcaligenes faecalis by Neplanocin A", Arch. Biochem. Biophys., 256, 50-55 (1987).

163.  B. Matuszewska and R T. Borchardt, "The Role of NAD+  in the Inhibition of S-Adenosylhomocysteine Hydrolase by Neplanocin A", J. Biol. Chem., 262, 265-268 (1987).

164.  M. Kawase, A. K. Sinhababu and R. T. Borchardt, "Tert-Butyldimethylsilyl Ethers of Phenols: Their One-Step Conversion to Benzyl or Methyl Esters and Utility in Regioselective ortho-Lithiation", Tetrahedron Letters28, 4139-4142 (1987).

165.  D. R. Borcherding, S. A. Scholtz and R. T. Borchardt, "The Synthesis of Analogs of Neplanocin A: Utilization of Optically Active Dihyroxycyclopentenones Derived from Carbohydrates", J. Org. Chem., 52, 5457-5461 (1987).

166.  M. Hasobe, J. G. McKee, D. R. Borcherding and R. T. Borchardt, "9-(Trans-2',Trans-3'-dihydroxycyclopent-4'-enyl)-Adenine and -3-Deazaadenine: Analogs of Neplanocin A Which Retain Potent Antiviral Activity But Exhibit Reduced Cytotoxicity", Antimicro. Agents Chemotherap.31, 1849-1851 (1987).

167.  R. G. Rosenfeld, H. Pham, B. Keller, R. T. Borchardt and W. M. Pardridge, "Structural Comparison of Receptors for Insulin, Insulin-Like Growth Factor I- and II- (IGF-I and IGF-II) in Brain and Blood Brain Barrier", Biochem. Biophys. Res. Commun.149, 159-166 (1987).

168.  M. Kawase, A. K. Sinhababu and R. T. Borchardt, "Silica Gel-Assisted Reductive Cyclization of 2-Nitro-b-piperidinostyrenes, Derived from 2-Nitrotoluenes, to Indoles", J. Heterocyclic Chem.24, 1499-1501 (1987).

169.  K. L. Audus and R. T. Borchardt, "Bovine Brain Microvessel Endothelial Cell Monolayers as a Model System for the Blood Brain Barrier" in Biological Approaches to the Controlled Delivery of Drugs (R. L. Juliano, Ed.), New York Academy of Science, New York, NY, Vol. 507, p. 9-18, 1987.

170.  K. L. Audus, I. Hidalgo and R. T. Borchardt, "Biological Barriers to the Efficient Delivery of Peptide Drugs" in Topics in Pharmaceutical Sciences (D. D. Breimer and P. Speiser, Eds.), Elsevier Science Publishers, Amsterdam, p. 325-337, 1987.

171.  K. L. Audus and R. T. Borchardt, "The Use of Isolated Epithelial and Cultured Endothelial Cells to Elucidate Drug Transport Mechanisms", in Proceedings of the 10th International Congress of Pharmacology (M. J. Rand and C. Raper, Eds.), Elsevier Science Publishers, Amsterdam, p. 615-618, 1987.

172.  M. C. Guitton, D. Part, B. Keller, J. deGunzberg, R. T. Borchardt and M. Vernon, "S-Adenosylmethionine, S-Adenosylhomocysteine and S-Adenosylhomocysteine Hydrolase Variations During the Differentiation of Dictyostelium discordium"Cell Differentiation22, 203-210 (1988).

173.  A. Ghosh, R. T. Borchardt and A. K. Sinhababu, "Characterization of Norepinephrine Uptake in Murine Neuroblastoma Cells, Clone N-2a", Biogenic Amines, 5, 25-35 (1988).

174.  A. K. Sinhababu and R. T. Borchardt, "Molecular Mechanism of Biological Action of the Serotonergic Neurotoxin 5,7-Dihydroxytryptamine: A Commentary", NeurochemistryInternational12, 273-284 (1988).

175.  M. Hasobe, J. McKee, B. Keller, D. R. Borcherding and R. T. Borchardt, "Effects of 9-(Trans-2',Trans-3'-dihydroxycyclopent-4'-enyl)-Adenine and -3-Deazaadenine on the Metabolism of S-Adenosylhomocysteine in Mouse L-929 Cells", Mol. Pharmacol.33, 713-720 (1988).

176.  B. T. Keller, K. R. Smith and R. T. Borchardt, "Transport Barriers to Absorption of Peptides", Netherlands Archives of Pharmaceutical Sciences, Pharmaceutisch Weekblad10, 38-39 (1988).

177.  M. Kawase, A. K. Sinhababu and R. T. Borchardt, "Desilylation of tert-butyldimethylsilyl Ethers of Phenols", Synthesis, 710-712 (1988).

178.  J.B.M.M. vanBree, K. L. Audus and R. T. Borchardt, "Carrier-Mediated Transport of Baclofen Across Monolayers of Bovine Brain Endothelial Cells in Primary Culture", Pharmaceutical Res., 5, 369-371, 1988.

179.  B. T. Keller and R. T. Borchardt, "Inhibition of S-Adenosylmethionine-Dependent Transmethylation as an Approach to the Development of Antiviral Agents" in Antiviral Drug Development - A Multidisciplinary Approach (E. De Clercq and R. T. Walkers, Ed.), Plenum Press, New York, p. 123-138, 1988.

180.  S. R. Narayanan and R. T. Borchardt, "An Improved Method for Purification of Bovine Liver S-Adenosylhomocysteine Hydrolase by Affinity Chromatography on Blue Dextran Agarose", Biochem. Biophys. Acta965, 22-28 (1988).

181.  K. R. Smith, A. Kato and R. T. Borchardt, "Characterization of Specific Receptors for Atrial Natriuretic Factor on Cultured Bovine Brain Capillary Endothelial Cells", Biochim. Biophys. Res. Commun., 157, 308-314 (1988).

182.  D. R. Borcherding, M. Hasobe, S. R. Narayanan, J. McKee, B. Keller and R. T. Borchardt, "Potential Inhibitors of S-Adenosylmethionine-Dependent Methyltransferases. 11. Molecular Dissections of Neplanocin A as Potential Inhibitors of S-Adenosylhomocysteine Hydrolase", J. Med. Chem.31, 1729-1738 (1988).

183.  S. R. Narayanan, B. Keller, D. R. Borcherding, S. A. Scholtz, and R. T. Borchardt, 9-(Trans-2',Trans-3'-dihydroxycyclopent-4'-enyl)-Adenine and -3-Deazaadenine: Potent Inhibitors of Bovine Liver S-Adenosylhomocysteine Hydrolase", J. Med. Chem.31, 500-503 (1988).

184.  R. T. Borchardt, "S-Adenosyl-L-Methionine-Dependent Methyltransferases: Potential Targets for Drug Design" in Perspectives in Psychopharmacology: A Collection of Papers in Honor of Earl Usdin (J. D. Barchas and W. E. Bunney, Jr., Eds.), Alan R. Liss, Inc., New York, NY, p. 281-290, 1988.

185.   A. K. Sinhababu and R. T. Borchardt, "Independent Synthesis of 5-hydroxytryptamine-4,7-dione - The Neurocytotoxic Product of Autoxidation of 5,7-Dihydroxytryptamine", J. Heterocycl. Chem., 25, 1155-1159 (1988).

186.  G.K.E. Scriba, R. T. Borchardt, J. A. Zirrolli and P. V. Fennessey, "Selected Ion Monitoring Gas Chromatographic-Mass Spectrometric Analysis of Catecholamines: Enhancement of Sensitivity by a Single Clean-up Step on Sephadex G-10", J.Chromatography: Biomedical Applications, 433, 31-40 (1988).

187.  G.K.E. Scriba, J. A. Hower, N. Y. Liang, P. V. Fennessey and R. T. Borchardt, "Effects of Ibopamine and Its Active Metabolite Epinine on the Catecholamine Content of Rat Hypothalamus and Brainstem In Vitro", J. Pharmacol. Exptl. Therap., 247, 609-616 (1988).

188.   I. J. Hidalgo, R. T. Borchardt and T. Raub, "Biochemical, Histological and Physicochemical Characterization of Human Adenocarcinoma Cells (Caco-2) as a Model System for Studying Mucosal Transport and Metabolism of Drugs", Gastroenterology96, 736-749 (1989).

189.   R. T. Borchardt, N. A. Mazer, J. H. Rytting, E. Shek, E. Ziv, E. Touitou and W. I. Higuchi, "The Delivery of Peptides", J. Pharm. Sci., 78, 883-892 (1989).

190.   K. R. Smith and R. T. Borchardt, "Permeability and Mechanism of Albumin, Cationized Albumin and Glycosylated Albumin Transcellular Transport Across Monolayers of Cultured Brain Capillary Endothelial Cells", Pharmaceutical Res., 6, 466-473 (1989).

191.   M. J. Wolfe, D. R. Borcherding and R. T. Borchardt, "A 9-Step Enantiospecific Total Synthesis of (-) Aristeromycin from D-Ribonolactone", Tetrahedron Letters30, 1453-1456 (1989).

192.   G.K.E. Scriba and R. T. Borchardt, "Metabolism of Catecholamine Esters by Cultured Bovine Brain Microvessel Endothelial Cells", J. Neurochem.53,  610-615 (1989).

193.   G.K.E. Scriba and R. T. Borchardt, "Metabolism of 1-Methyl-4-Phenyl-1,2,3,6-Tetrahydropyridine (MPTP) by Bovine Brain Capillary Endothelial Cell Monolayers", Brain Res., 501, 175-178 (1989).

194.   J. E. Chastain,Jr. and R. T. Borchardt, "L-a-Methyldopa Transport Across Bovine Brain Microvessel Endothelial Cell Monolayers, A Model of the Blood Brain Barrier", Neurosci. Res. Commun.4, 147-152 (1989).

195.   S. D. Paisley, M. S. Wolfe and R. T. Borchardt, "Oxidation of Neplanocin A to the Corresponding 3'-Ketocyclopentenyl Derivative by S-Adenosylhomocysteine (AdoHcy) Hydrolase", J. Med. Chem., 32, 1415-1418 (1989).

196.   S. D. Paisley and R. T. Borchardt, "Elucidation of the Mechanism by Which 9-(Trans-2'-Trans-3'-Dihydroxycyclopent-4'-enyl)-Adenine Inactivates S-Adenosylhomocysteine Hydrolase", Nucleosides and Nucleotides8, 689-698 (1989).

197.   A. K. Sinhababu and R. T. Borchardt, "Mechanism of Autoxidation of 5,7-Dihydroxytryptamine: 18O is Incorporated on C-4 During Autoxidation with 18O2", J. Amer. Chem. Soc.111, 2230-2233 (1989).

198.   M. V. Shah, K. L. Audus and R. T. Borchardt, "The Application of Bovine Brain Microvessel Endothelial Cell Monolayers Grown Onto Polycarbonate Membranes In Vitro to Estimate the Potential Permeability of Solutes Through the Blood Brain Barrier", Pharmaceutical Res., 6,  624-627 (1989).

199.   M. Hasobe, J. G. McKee, H. Ishii and R. T. Borchardt, "The Relationship Between the Intracellular Concentration of S-Adenosylhomocysteine and Inhibition of Vaccinia Virus Replication Versus Inhibition of Murine L929 Cell Growth", Antimicro. AgentsChemotherap., 33, 828-834 (1989).

200.   M. Hasobe, J. G. McKee, H. Ishii, M. Cools, R. T. Borchardt and E. De Clercq, "Elucidation of the Mechanism Responsible for the Synergistic Effects of DL-Homocysteine (Hcy) on the Anti Vaccinia Virus Effects of the S-Adenosylhomocysteine (AdoHcy) Hydrolase Inhibitor 9-(Trans-2',Trans-3'-Dihydroxycyclopent-4'-enyl)-Adenine", Mol. Pharmacol., 36, 490-496 (1989).

201.  I. J. Hidalgo, A. Kato and R. T. Borchardt, "Epidermal Growth Factor (EGF) Binding in a Human Colon Carcinoma Cell Line (Caco-2)", Biochem. Biophys. Res. Commun.158, 317-324 (1989).

202.   E. De Clercq, M. Cools, V. E.Marquez, D. R. Borcherding, R. T. Borchardt, J. C. Drach, S. Kitaoka and T. Konno, "Broad Spectrum Antiviral Activity of New Neplanocin A Analogs", Antimicrobial Agents and Chemotherapy33, 1291-1297(1989).

203.   A. Barancyk-Kuzma, K. L. Audus and R. T. Borchardt, "Substrate Specificity of Phenol Sulfotransferase from Primary Cultures of Bovine Brain Microvessel Endothelium", Neurochem. Res., 14, 689-691 (1989).

204.   M. Manning, K. Patel and R. T. Borchardt, "Protein Stability: Pharmaceutical Implications", Pharmaceutical Res., 6, 903-918 (1989).

205.   M. Cools, M. Hasobe, E. De Clercq and R. T. Borchardt, "Mechanism of the Synergistic Antiviral and Cytostatic Activity of (RS)-3-(Adenin-9-yl) 2-Hydroxypropanoic Acid Isobutyl Ester and D,L-Homocysteine", Biochem. Pharmacol., 39, 195-202 (1990).

206.   I. Votruba, M. Hasobe, A. Holy and R. T. Borchardt, "2-Methylpropyl Ester of 3-(Adenin-9-yl)-2-hydroxypropanoic Acid: Mechanism of Antiviral Action of Vaccinia Virus-Infected L929 Cells", Biochem. Pharmacol., 39, 1573-1580 (1990).

207.   I. J. Hidalgo and R. T. Borchardt, "Transport of a Large Neutral Amino Acid (Phenylalanine) in a Human Intestinal Epithelial Cell Line: Caco-2", Biochim. Biophys. Acta1028, 25-30 (1990).

208.   I. J. Hidalgo and R. T. Borchardt, "Transport of Bile Acids in a Human Intestinal Epithelial Cell Line: Caco-2", Biochim. Biophys. Acta.1035, 97-103 (1990).

209.   N. P. Bhatt, K. Patel and R. T. Borchardt, "Chemical Pathways of Peptide Degradation: I. Deamidation of Adrenocorticotropic Hormone", Pharmaceutical Res., 7, 593-599 (1990).

210.   K. Patel and R. T. Borchardt, "Chemical Pathways of Peptide Degradation: II.  Kinetics of Deamidation of the Asparaginyl Residue in a Model Hexapeptide", Pharmaceutical Res., 7, 703-711 (1990).

211.   K. Patel and R. T. Borchardt, "Chemical Pathways of Peptide Degradation: III.  Effect of Primary Sequence on the Pathways of Deamidation of Asparaginyl Residues in Hexapeptides", Pharmaceutical Res., 7, 787-793 (1990).

212.   D. L. Kramer, C. W. Porter, R. T. Borchardt and J. R. Sufrin, "Combined Modulation of S-Adenosylmethionine Biosynthesis and S-Adenosylhomocysteine Metabolism Enhances Inhibition of Methylation Reactions and Cell Growth", Cancer Res., 50, 3838-3842 (1990).

213.   M. Kawase, A. K. Sinhababu and R. T. Borchardt, "Mechanism of Autooxidation of 5,7-Dihydroxytryptamine: Effects of Fluorine Substitution in Positions 4 and/or 6", Chem. Pharm. Bull.38, 2939-2946 (1990).

214.   K. Audus, R. Bartel, I. Hidalgo and R. T. Borchardt, "The Use of Cultured Epithelial and Endothelial Cells for Drug Transport and Metabolism Studies", Pharmaceutical Res., 7, 435-451 (1990).

215.   M. S. Wolfe, B. Anderson, D. R. Borcherding and R. T. Borchardt, "Enantiospecific Syntheses of Aristeromycin and Neplanocin A", J. Org. Chem., 55, 4712-4717 (1990).

216.   S. M. Ali, K. Ramesh and R. T. Borchardt, "Efficient Enantioselective Syntheses of Carbocyclic Nucleosides and Prostaglandin Synthons", Tetrahedron Letters31, 1509-1512 (1990).

217.   M. Kawase, A. K. Sinhababu, E. M. McGhee, T. D. Milby and R. T. Borchardt, "Molecular Mechanism of Neurodegenerative Effects of 5,6-Dihydroxytryptamine.  Syntheses and Biological Evaluation of 4-Fluoro-, 7-Fluoro- and 4,7-Difluoro-5,6-dihydroxytryptamines", J. Med. Chem., 33, 2204-2211 (1990).

218.   J. E. Chastain, Jr. and R. T. Borchardt, "Acivicin Transport Across Bovine Brain Microvessel Endothelial Cell Monolayers, A Model of the Blood Brain Barrier", Neurosci. Res. Commun.,  6, 51-55 (1990).

219.   K. L. Amsberry and R. T. Borchardt, "The Lactonization of 2'-Hydroxyhydrocinnamic Acid Amides: A Potential Prodrug for Amines", J. Org. Chem., 55, 5867-5877 (1990).

220.   P. K. Shah and R. T. Borchardt, "Liquid Chromatographic Analysis of Leu-Enkephalin and Its Metabolites in Homogenates of Human Skin and Cultured Human Keratinocytes", J. Pharm. Biomed. Anal.,  8, 457-462 (1990).

221.   K. Patel and R. T. Borchardt, "Deamidation of Asparaginyl Residues in Proteins: A Potential Pathway for Chemical Degradation of Proteins in Lyophilized Dosage Forms", J. Parenteral Sci. Technol.44, 300-301 (1990).

222.   R. T. Borchardt, "Assessment of Transport Barriers Using Cell and Tissue Culture Systems", Drug Devel. Indust. Pharm., 18, 2595-2612 (1990).

223.  P. K. Shah, I. Hidalgo and R. T. Borchardt, "A Simple Diffusion Device to Study Transport Across Cells Cultured on Microporous Membranes", Int. J. Pharmaceutics63, 281-283 (1990).

224.   M. Hu and R. T. Borchardt, "Mechanism of L-a-Methyldopa Transport Through a Monolayer of Polarized Human Intestinal Epithelial Cells (Caco-2)", Pharmaceutical Res.7, 1313-1319 (1990).

225.   K. Audus and R. T. Borchardt, "Transport of Macromolecules Across the Capillary Endothelium" in Handbook of Experimental Pharmacology (R. L. Juliano, Ed.), Springer, Berlin, p. 43-70, 1991.

226.   J. B. Baker, I. Hidalgo and R. T. Borchardt, "Intestinal Epithelial and Vascular Endothelial Barriers to Peptide and Protein Delivery" in Peptide and Protein Drug Delivery (V.H.L. Lee, Ed.), Marcel Dekker, Inc., New York, p. 359-390, 1991.

227.   G.K.E. Scriba and R. T. Borchardt, "Metabolism of Catecholamine Prodrugs in Cultured Brain Microvessel Endothelial Cells" in Pharmaceutical Applications of Cell and Tissue Culture to Drug Transport (G. Wilson, S. S. Davis and L. Illum, Eds.), Plenum Press, New York, p. 191-202 (1991).

228.   I. J. Hidalgo and R. T. Borchardt, "Carrier-Mediated Transport of Bile Acids and Amino Acids in Caco-2 Cells", in Pharmaceutical Applications of Cell and Tissue Culture to Drug Transport (G. Wilson, S. S. Davis and L. Illum, Eds.), Plenum Press, New York, p. 77-92 (1991).

229.   R. T. Borchardt, I. J. Hidalgo, K. M. Hillgren and M. Hu, "Pharmaceutical Applications of Cell Culture - An Overview", in Pharmaceutical Applications of Cell and Tissue Culture to Drug Transport (G. Wilson, S. S. Davis and L. Illum, Eds.), Plenum Press, New York, p. 1-14 (1991).

230.   P. K. Shah and R. T. Borchardt, "A Comparison of Aminopeptidase Activity and Peptide Metabolism in Cultured Mouse Keratinocytes and Neonatal Mouse Epidermis", Pharmaceutical Res., 8, 70-75 (1991).

231.  I. J. Hidalgo, K. M. Hillgren, G. M. Grass and R. T. Borchardt, "Characterization of the Unstirred Water Layer in Caco-2 Cells Using a Novel Diffusion Cell", Pharmaceutical Res., 8, 223-227 (1991).

232.   J. C. Yeh, R. T. Borchardt and A. Vedani, "A Molecular Model of the Active Site of S-Adenosylhomocysteine Hydrolase", J. Computer-Aided Mol. Design5, 213-234 (1991).

233.  P. K. Shah, R. L. Bartel and R. T. Borchardt, "Permeability Characteristics of Cultured Mouse Keratinocytes Compared to Hairless Mouse Skin", Int. J. Pharmaceutics,  68, 285-288 (1991).

234.  K. L. Amsberry and R. T. Borchardt, "Prodrugs Which Utilize Hydroxy Amide Lactonization I: A Potential Redox Sensitive Prodrug for Amines", Pharmaceutical Res.8, 323-330 (1991).

235.  K. L. Amsberry, A. E. Gerstenberger and R. T. Borchardt, "Prodrugs Which Utilize Hydroxy Amide Lactonization II: A Potential Esterase Sensitive Prodrug for Amines", Pharmaceutical Res.8, 455-461 (1991).

236.  M. S. Wolfe and R. T. Borchardt, "S-Adenosyl-L-homocysteine Hydrolase as a Target for Antiviral Chemotherapy", J. Med. Chem.34, 1521-1530 (1991).

237.  J. R. Sufrin, A. J. Spiess, D. L. Kramer, P. R. Libby, J. T. Miller, R. T. Bernacki, Y. Lee, R. T. Borchardt and C. W. Porter, "Targeting 5'-Deoxy-5'-(methylthio)-adenosine Phosphorylase by 5'-Haloalkyl Analogues of 5'-Deoxy-5'-(methylthio) adenosine", J. Med. Chem., 34, 2600-2606 (1991).

238.   Y. Takakura, K. Audus and R. T. Borchardt, "Blood-Brain Barrier: Transport Studies in Isolated Brain Capillaries and in Cultured Brain Endothelial Cells", in Advances in Pharmacology (J. T. August, M. W. Anders, F. Muirad, Eds.), Academic Press, San Diego, CA, Vol. 22, p. 137-165, 1991.

239.   Y. Takakura, S. L. Kuentzel, T. Raub, A. Davies, S. A. Baldwin and R. T. Borchardt, "Hexose Uptake in Primary Cultures of Bovine Brain Microvessel Endothelial Cells I.  Basic Characteristics and Effects of D-Glucose and Insulin", Biochim. Biophys. Acta, 1070, 1-10 (1991).

240.  Y. Takakura, A. Trammel, S. L. Kuentzel, T. J. Raub, A. Davies, S. A. Baldwin and R. T. Borchardt. "Hexose Uptake in Primary Cultures of Bovine Brain Microvessel Endothelial Cells. II.  Effect of Conditioned Media from Astroglial and Glioma Cells", Biochim. Biophys. Acta,  1070, 11-19 (1991).

241.  A. Baranczyk-Kuzma, J. A. Garren, I. J. Hidalgo and R. T. Borchardt, "Substrate Specificity and Some Properties of Phenol Sulfotransferase from Human Intestinal Caco-2 Cells", Life Sci.49, 1197-1206(1991).

242.  A. Baranczyk-Kuzma, K. L. Audus, F. L. Guillot and R. T. Borchardt, "Effects of Selected Vacoactive Substances on Adenylate Cyclase Activity in Brain, Isolated Brain Microvessels and Primary Cultures of Brain Microvessel Endothelial Cells", Neurochemical Research17, 209-214 (1992).

243.   Y. Takakura, K. Audus and R. T. Borchardt, "Cultured Brain Microvessel Endothelial Cells as In Vitro Models of the Blood Brain Barrier", in "Drug Bioavailability and Blood Brain Barrier" (J. Frankenheim and R. M. Brown, Eds.), National Institute of Drug Abuse Research Monograph, #120, DHHS Pub. No. (ADM) 92-1910, Washington, DC, Supt. of Docs., U.S. Govt. Printing Office, pp. 138-152, 1992.

244.  M. S. Wolfe, Y. Lee, W. K. Bartlett, D. R. Borcherding and R. T. Borchardt, "4'-Modified Analogs of Aristeromycin and Neplanocin A: Syntheses and Inhibition of S-Adenosylhomocysteine Hydrolase", J. Med. Chem., 35, 1782-1791 (1992).

245.   I. J. Hidalgo, K. M. Hillgren, G. M. Grass and R. T. Borchardt, "A New Side by Side Diffusion Cell Useful for Studying Transport Across Epithelial Cell Monolayers", In Vitro-Cellular and Developmental Biology, 28A, 578-580, 1992.

246.  K. Audus, P. Chikhale, D. Miller S. E. Thompson and R. T. Borchardt, "Brain Uptake: Influence of Chemical and Biological Factors" in "Advances in Drug Research" (B. Testa, Ed.), Academic Press, London, Vol. 23, 1-64, 1992.

247.  S. Liu, M. S. Wolfe and R. T. Borchardt, "Rational Approaches to the Design of Antiviral Agents Based on S-Adenosyl-L-homocysteine Hydrolase as a Molecular Target", Antiviral Research19, 247-265 (1992).

248.  C. Oliyai, C. Schoneich, G. Wilson and R. T. Borchardt, "Chemical and Physical Stability of Protein Pharmaceuticals" in "Topics in Pharmaceutical Sciences - 1991", (D.J.A. Crommelin and K. K. Midha, Eds.), Medpharm Scientific Publishers, Stuttgart, 23-46 (1992).

249.  M. Hu and R. T. Borchardt, "Transport of a Large Neutral Amino Acid in a Human Intestinal Epithelial Cell Line (Caco-2): Uptake and Efflux of Phenylalanine", Biochim. Biophys. Acta,  1135, 233-244 (1992).

250.  D. Miller, K. Audus and R. T. Borchardt, "Application of Cultured Endothelial Cells of the Brain Microvasculature in the Study of the Blood Brain Barrier", J. Tissue Cult. Meth.14, 217-224 (1992).

251.  M. J. Robins, V. Samano, W. Zhang, J. Balzarini, E. DeClercq, R. T. Borchardt, Y. Lee and C. S. Yuan, "Nucleic Acid Related Compounds. 74, Synthesis and Biological Activity of 2' (and 3')-Deoxy 2'(and 3')-Methylene Nucleoside Analogs that Function as Mechanism-Based Inhibitors of S-Adenosyl-L-Homocysteine Hydrolase and/or Ribonucleotide Reductase", J. Med. Chem.35, 2283-2293 (1992).

252.  K. Ramesh, M. S. Wolfe, Y. Lee., D. Vander Velde and R. T. Borchardt, "Synthesis of Hydroxylated Cyclohexenyl and Cyclohexanyl Adenines as Potential Inhibitors of S-Adenosylhomocysteine Hydrolase", J. Org. Chem.57, 5861-5868 (1992).

253.  R. A. Gray, D. G. Vander Velde, R. T. Borchardt, C. J. Burke, C. R. Middaugh and M. C. Manning, "The Use of Computer-Aided Modeling to Understand Peptide Transport", Chemical Design Automation News7, 36-39, 1992.

254.  R. T. Borchardt, "Rational Delivery Strategies to Circumvent Physical and Metabolic Barriers to the Oral Absorption of Peptides" in "Oral Delivery of Peptides-From Theory to Practice, 1991", Capsugel, Basel, Switzerland, pp. 11-19, 1992.

255.  C. L. Stevenson, T. D. Williams, R. J. Anderegg and R. T. Borchardt, "Identification and Quantification of Tetrapeptide Deamidation Products by Mass Spectrometry", J. Pharm. Biomed. Anal.10, 567-575 (1992).

256.  J. L. Wolfe, D. Vander Velde and R. T. Borchardt, "Facilitated Intramolecular Conjugate Addition of Amides of 3-(3',6'-Dioxo-2',4'-Dimethyl-1',4'-Cyclohexadiene 3,3-Dimethylpropionic Acid. I. Product Elucidation", J. Org. Chem.57, 6138-6142 (1992).

257.  A. Baranczyk-Kuzma, K. L. Audus and R. T. Borchardt, "Properties of Phenol Sulfotransferase from Brain of the Monkey Rhesus Macaque" Acta Biochim Polan.39, 153-158 (1992).

258.  S. Liu, S. M. Ali, M. S. Wolfe, C. S. Yuan and R. T. Borchardt, "Syntheses and Evaluation of 4',5'-Dehydro-5'-Fluoroaristeromycins as Inhibitors of S-Adenosyl-L-Homocysteine Hydrolase", Bioorg. Med. Chem. Letters2, 1741-1744 (1992).

259.  H. Ishii, M. Hasobe, J. G. McKee and R. T. Borchardt, "Synergistic Antiviral Effects of Inhibitors of S-Adenosylhomocysteine Hydrolase and Ribavirin,  Antiviral Chem. Chemotherap, 4, 127-130 (1993).

260.  C. Oliyai and R. T. Borchardt, "Chemical Pathways of Peptide Degradation. IV.  Pathways, Kinetics and Mechanism of Degradation of an Aspartyl Residue in a Model Hexapeptide", Pharmaceutical Res.10, 95-102 (1993).

261.  A. Baranzcyk-Kuzma, K. L. Audus and R. T. Borchardt, "Sulfation of Catecholamines, Hypertensive and Hypotensive Drugs by Monkey Brain Cortex Enzymes, Acta Biochim. Polan., 40, 189-192 (1993).

262.  C. S. Yuan, J. Yeh, S. Liu and R. T. Borchardt, "Mechanism of Inactivation of S-Adenosylhomocysteine Hydrolase by (Z)-4',5'-Didehydro-5'-Deoxy-5'-Fluoroadenosine", J. Biol. Chem., 268, 17030-17037 (1993).

263.  S. Raeissi and R. T. Borchardt, "Cultured Human Adenocarcinoma Cells (Caco-2) As a Model to Study the Mechanism by Which Adjuvants Enhance Intestinal Permeability of Drugs", S.T.P. Pharma Sciences, 3, 56-62 (1993).

264.  Ka-Yun Ng and R. T. Borchardt, "Biotin Transport in a Human Intestinal Epithelial Cell Line (Caco-2)", Life Sci.53, 1121-1127 (1993).

265.  C. S. Yuan, J. Yeh, T. C. Squier, A. Rawitch and R. T. Borchardt, "Ligand-Dependent Intrinsic Fluorescence Changes of S-Adenosylhomocysteine Hydrolase: Implications About the Mechanism of Inhibitor Induced Inactivation", Biochemistry32, 10414-10422 (1993).

266.   M. Hasobe, H. Liang, D. B. Ault-Riche, D. Borcherding, M. S. Wolfe and R. T. Borchardt, "(1'R,2'S,3'R)-9-(2',3'-dihydroxycyclopentan-1'-cyl)-Adenine and -3-Deazaadenine: Analogs of Aristeromycin Which Exhibit Potent Antiviral Activity with Reduced Cytotoxicity", Antiviral Chemistry and Chemotherapy., 4, 245-248 (1993).

267.   D. B. Ault-Riche, Y. Lee, C.-S. Yuan, M. Hasobe, M. S. Wolfe, D. R. Borcherding and R. T. Borchardt, "Effects of 4'-Modified Analogs of Aristeromycin on Metabolism of S-Adenosylhomocysteine in Mouse L929 Cells", Mol. Pharmacol., 43, 989-997 (1993).

268.  A. S. Tang, P. J. Chikhale, P. K. Shah and R. T. Borchardt, "Utilization of a Human Intestinal Epithelial Cell Culture System (Caco-2) for Evaluating Cytoprotective Agents", Pharmaceutical Res., 10, 1620-1626 (1993).

269.  C. L. Stevenson, R. J. Anderegg and R. T. Borchardt, "Probing the Helical Content of Growth Hormone Releasing Factor Analogs Using Electrospray Mass Spectrometry", J. Amer. Soc. Mass Spectrometry, 4, 646-651 (1993).

270.  C. L. Stevenson, R. J. Anderegg and R. T. Borchardt, "Comparison of Separation and Detection Techniques for Human Growth Hormone Releasing Factor and the Products Derived from Deamidation", J. Pharm. Biomed. Anal., 11, 367-373 (1993).

271.  C. L. Stevenson, M. E. Donlan, A. R. Friedman and R. T. Borchardt, "Solution Conformation of Leu27-hGRF (1-32) NH2 and Its Deamidation Products by 2D NMR", Int. J. Peptide Protein Res.42, 24-32 (1993).

272.  C. L. Stevenson, A. R. Friedman, T. M. Kubiak, M. E. Donlan,  and R. T. Borchardt, "Effect of Secondary Structure on the Rate of Deamidation of Several Growth Hormone Releasing Factor Analogs",  Int. J. Peptide Protein Res.42, 497-503 (1993).

273.  Shihong Li, C. Schöneich, G. S. Wilson and R. T. Borchardt, "Chemical Pathways of Peptide Degradation. V.  Ascorbic Acid Promotes Rather than Inhibits the Oxidation of Methionine to Methionine Sulfoxide in Small Model Peptides", Pharmaceutical Res.10, 1572-1579 (1993).

274.  D. C. Kim, P. S. Burton and R. T. Borchardt, "The Correlation of the Permeability Coefficients for a Series of Peptides Using an In Vitro Cell Culture Model (Caco-2) and Those Using In Situ Perfused Rat Intestinal Model", Pharmaceutical Res., 10, 1710-1714 (1993).

275.  S. Liu, S. Wnuk, M. J. Robins, C. S. Yuan and R. T. Borchardt, "Adenosine 5'-Carboxaldehyde: A Potent Inhibitor of S-Adenosyl-L-homocysteine Hydrolase", J. Med. Chem.36, 883-887 (1993).

276.  Ka-yun Ng, G. Grass, H. Lane and R. T. Borchardt, "Characterization of the Unstirred Water Layer in Cultured Brain Microvessel Endothelial Cells", In Vitro Cell Dev. Biol.,  29A, 627-629 (1993).

277.  A. Baranczyk-Kuzma, D. Drobisz, K. L. Audus and R. T. Borchardt, "Sulfation of Hypertensive and Hypotensive Drugs by Monkey Brain Phenol Sulfotransferase", Neurochem. Res., 18, 783-786 (1993).

278.   C. Schöneich, F. Zhao, G. S. Wilson and R. T. Borchardt, "Iron-Thiolate Induced Oxidation of Methionine to Methionine Sulfoxide in Small and Medium Sized Model Peptides. Catalysis by Histidine", Biochim. Biophys. Acta1158, 307-322 (1993).

279.  D. C. Kim, A. W. Harrison, M. J. Ruwart, K. F. Wilkinson, J. F. Fisher, I. J. Hidalgo and R. T. Borchardt, "Evaluation of the Bile Acid Transporter for the Enhancement of Renin-Inhibitory Peptide Intestinal Permeability", J. Drug Targeting,  1, 347-359 (1993).

280.  M. J. Robins, S. F. Wnuk, K. B. Mullah, N. K. Dalley, R. T. Borchardt, Y. Lee and C. S. Yuan, "Adenosine-Derived 5'-a-Fluoro Thioether, Sulfoxide, Sulfone and (5'-Halo) Methylene Analogous.  Inhibition of S-Adenosyl-L-homocysteine Hydrolase" in Nucleosides and Nucleotides as Antitumor and Antiviral Agents (C. K. Shu and D. C. Baker, Eds.), Plenum Press, New York, NY, pp. 115-126, 1993.

281.  C. Oliyai and R. T. Borchardt, "Chemical Instability of Proteins in Solution and Lyophilized Formulations" in "Protein Formulations and Delivery" (J. Cleland and R. Langer, Eds.), ACS Symposium Series, Washington, DC, p. 46-58, 1994.

282.  E. Brunt Chikhale, Ka-yun Ng, P. S. Burton and R. T. Borchardt, "Hydrogen Bond Potential as a Determinant of the In Vitro and In Situ Blood Brain Barrier Permeability of Peptides", Pharmaceutical Res., 11412-419 (1994).

283.  M. J. Robins, S. F. Wnuk, K. B. Mullah, N.  K. Dulley, C. S. Yuan, Y. Lee and R. T. Borchardt, "Nucleic Acid Related Compounds. 80. Synthesis of 5'-S-(Alkyl and Aryl)-5'-Fluoro-5'-Thioadenosines with Xenon Difluoride or (Diethylamino) Sulfur Trifluoride, Hydrolysis in Aqueous Buffer and Inhibition of S-Adenosyl-L-homocysteine Hydrolase by Adenosine 5'-Aldehyde-Derived Species", J. Org. Chem.59, 544-555 (1994).

284.  R. Gray, D. Vander Velde, C. J. Burke, M. Manning, C. R. Middaugh and R. T. Borchardt, "Delta-Sleep Inducing Peptide: Investigation of Its Solution Structure(s) and Its Potential Relationship to Permeability", Biochemistry33, 1323-1331 (1994).

285.  X. Guan and R. T. Borchardt, "A Convenient Method for the Syntheses of Indole-3-Acetic Acids", Tetrahedron Letters35, 3013-3016 (1994).

286.  C. Oliyai and R. T. Borchardt, "Chemical Pathways of Peptide Degradation. VI.  Effects of  Primary Sequence on the Pathways and Kinetics of Degradation of an Aspartyl Residue in a Model Hexapeptide", Pharmaceutical Res.11, 751-758 (1994).

287.  C. Oliyai, J. Patel, L. Carr and R. T. Borchardt, "Solid State Stability of Lyophilized Formulations of an Asparaginyl Residue in a Model Hexapeptide", J. Parenteral Sci. Tech.,  48, 167-173 (1994).

288.  C. Oliyai, J. P. Patel, L. Carr and R. T. Borchardt, "Chemical Pathways of Peptide Degradation. VII.  Kinetics and Mechanism of Degradation of Lyophilized Formulations of an Aspartyl Residue in a Model Hexapeptide", Pharmaecutical Res., 11, 901-908 (1994).

289.   R. J. Anderegg, D. Wagner, C. Stevenson and R. T. Borchardt, "The Mass Spectrometry of Helical Unfolding in Peptides", J. Amer. Chem. Soc. Mass Spectrom.5, 425-433(1994).

290.  I. Islam, K. Y. Ng, K. T. Chang, T. J. McQuade, J. O. Hui, K. F. Wilkinson, B. D. Rush, M. J. Ruwart, R. T. Borchardt and J. F. Fisher, "Evaluation of a Vitamin Clocking Strategy for Improving the Availability of Oligopeptide Therapeutics: Biotinylated HIV Protease Inhibitors", J. Med. Chem.37, 293-304 (1994).

291.  D. Miller, B. T. Keller and R. T. Borchardt, "Identification and Distribution of Insulin Receptors in Cultured Bovine Brain Microvessel Endothelial Cells: Possible Function in Insulin Processing in the Blood Brain Barrier", J. Cellular Physiol.161, 333-341 (1994).

292.   C. S. Yuan, S. Liu, S. F. Wnuk, M. J. Robins and R. T. Borchardt, "Mechanism of Inactivation of S-Adenosylhomocysteine Hydrolase by (E)-5',6'-Didehydro-6'-Deoxy-6'-Halo-Homoadenosine", Biochemistry,  33, 3758-3765 (1994).

293.  R. T. Borchardt, "Rational Strategies to Enhance the Intestinal Permeability of Peptides" in Peptides: Chemistry, Structure and Biology-Proceedings of the 13th American Peptide Symposium (R. S. Hodges and J. A. Smith, Eds.), Escom Science Publishers, B.V., Leiden, The Netherlands, pp. 827-829, 1994.

294.  R. T. Borchardt, "Rational Strategies for the Design of Peptides with Enhanced Oral Delivery", Drug Devel. Indust. Pharm.20, 469-483 (1994).

295.  C. S. Yuan, S. F. Wnuk, S. Liu, M. J. Robins and R. T. Borchardt, "(E)-5',6'-Didehydro-6'-Deoxy-6'-Fluoro-Homoadenosine: A Substrate that Measures the Hydrolytic Activity of S-Adenosylhomocysteine Hydrolase", Biochemistry33, 12305-12311 (1994).

296.  P. J. Chikhale and R. T. Borchardt, "Metabolism of a-MethylDOPA in Cultured Intestinal Epithelial (Caco-2) Cells: Correlation with Metabolism In Vivo", Drug Metab. Dispos.22, 592-601 (1994).

297.  S. F. Wnuk, C. S. Yuan, R. T. Borchardt, J. Balzarini, E. DeClercq and M. J. Robins, "Nucleic Acid Related Compounds 84.  Synthesis of 6'(E and Z)-Halogenohomovinyl Derivatives of Adenosine, Inactivation of S-Adenosyl-L-homocysteine Hydrolase and Correlation of Anticancer and Antiviral Activities with Enzyme Inhibition", J. Med. Chem., 37, 3579-3587 (1994).

298.  D. B. Ault-Riche, C. S. Yuan and R. T. Borchardt, "A Single Mutation at Lysine 426 of Human Placental S-Adenosylhomocysteine Hydrolase Inactivates the Enzyme", J. Biol. Chem., 269, 31472-31478 (1994).

299.  D. W. Miller, L. Ng, A. Kato, E. Chikhale and R. T. Borchardt, "Cell Culture Models for Examining Peptide Absorption" in "Peptide-Based Drug Design: Controlling Transport and Metabolism" (M. Taylor and G. Amidon, Eds.), ACS Books, Washington, DC, pp. 475-500, 1995.

300.  L. S. Jeong, V. E. Marquez, C. S. Yuan and R. T. Borchardt, "4,1'-a-Methanocarbocyclic Adenosine Analogues as Potential Inhibitors of S-Adenosylhomocysteine Hydrolase", Heterocycles41, 2651-2656 (1995).

301.  S. Li, C. Schöneich and R. T. Borchardt, "Chemical Pathways of Peptide Degradation. VIII.  Oxidation of Methionine in Small Model Peptides by Prooxidant/Transition Metal Ion Systems: Influence of Selective Scavengers for Reactive Oxygen Intermediates", Pharm. Res.12, 348-355 (1995).

302.  E. G. Chikhale, P. S. Burton and R. T. Borchardt, "The Effects of P-Glycoprotein on the Transport of Peptides Across the Blood-Brain Barrier in Rats", J. Pharmacol. Exptl. Therap.273, 298-303 (1995).

303.  E. G. Chikhale, P. J. Chikhale and R. T. Borchardt, "Carrier-Mediated Transport of the Antitumor Agent Acivicin Across the Blood-Brain Barrier", Biochem. Pharmacol., 49, 941-945 (1995).

304.  C. S. Yuan, S. Liu, S. F. Wnuk, M. J. Robins and R. T. Borchardt, "Rational Approaches to the Design of Mechanism-Based Inhibitors of S-Adenosylhomocysteine Hydrolase", Nucleosides and Nucleotides14, 439-447 (1995).

305.  A. Baranczyk-Kuzma, I. Barszczewska, R. T. Borchardt and K. L. Audus, "Sulfate Conjugation of Catecholamines and Their Derivatives in Monkey Brain", Biogenic Amines11, 281-294 (1995).

306.  K. Hillgren, A. Kato and R. T. Borchardt, "In Vitro Models to Study Intestinal Drug Absorption", Med. Res. Rev., 15, 83-109 (1995).

307.  S. Li., C. Schöneich and R. T. Borchardt, "Chemical Instability of Protein Pharmaceuticals: Mechanisms of Oxidation and Strategies for Stabilization", Biotech. Bioeng.48, 490-500 (1995).

308.  B. Wang, S. Liu and R. T. Borchardt, "The Development of a Novel Redox Sensitive Protecting Group for Amines Which Utilizes a Facilitated Lactonization Reaction", J. Org. Chem.60, 539-543 (1995).

309.  S. Li, T. H. Nguyen, C. Schöneich and R. T. Borchardt, "Metal-Catalyzed Oxidation of Human Relaxin", Biochemistry34, 5762-5772 (1995).

310.  Y. Takakura, T. Morita, M. Fujikawa, M. Hayashi, H. Sezaki, M. Hashida and R. T. Borchardt, "Characterization of LLC-PK1 Kidney Epithelial Cells as an In Vitro Model for Studying Renal Tubular Reabsorption of Protein Drugs", Pharmaceutical Res.12, 1968-1972 (1995).

311.  R. Gupta, C. S. Yuan, D. B. Ault-Riche and R. T. Borchardt, "Limited Proteolysis of S-Adenosylhomocysteine Hydrolase. Implication for Three-Dimensional Structure and for Conformational Changes", Arch. Biochem. Biophys.319, 365-371 (1995).

312.  R. T. Borchardt, "The Application of Cell Culture Systems in Drug Discovery and Development" (Editorial), J. Drug Targeting3, 179-182 (1995).

313.  S. Li, C. Schöneich and R. T. Borchardt, "The Chemical Instability of Proteins", Pharmaceutical News2, 12-16 (1995).

314.  P. F. Augustijns, K. Y. Ng, T. M. Williams and R. T. Borchardt, "Peptide Dipeptidase A Catalyzed Degradation of Delta Sleep-Inducing Peptide in Cultured Microvessel Endothelial Cells", Biochem. Biophys. Res. Commun., 210, 987-994 (1995).

315.  C. S. Yuan and R. T. Borchardt, "Photoaffinity Labeling of S-Adenosylhomocysteine Hydrolase by 8-Azidoadenosine Dialdehyde: Identification of Peptides in the Adenosine Binding Site", J. Biol. Chem. 270, 16140-16146 (1995).

316.  P. F. Augustijns and R. T. Borchardt, "Transport and Metabolism of Delta Sleep-Inducing Peptide (DSIP) in Cultured Human Intestinal Epithelial (Caco-2) Cell Monolayers", Drug Metab. Dispos., 23, 1372-1378 (1995).

317.  R. T. Borchardt, H. K. Lane, B. H. Hirst, P. L. Smith, K. L. Audus and A. Tsuji, "Application of Cell Culture Systems to Study Drug Transport and Metabolism" in Pharmacological Sciences' Perspective for Research and Therapy in the late 1990's, Birkhauser, Germany, 493-501 (1995).

318.  C. S. Yuan, S. Liu, S. Wnuk, M. J. Robins and R. T. Borchardt, "Design and Synthesis of S-Adenosylhomocysteine Hydrolase as Broad-Spectrum Antiviral Agents" in Advances in Antiviral Drug Design (E. De Clercq, Ed.), JAI Press, Inc., Greenwick, CT, Vol. 2, 41-88, 1996.

319.  I. Islam, R. R. Hinshaw, K. T. Chong, A. Kato, R. T. Borchardt and J. F. Fisher, "Synthesis and Antiviral Activity of [2-[[4-[3-[(1-Methylethyl)amino]-2-Pyridyl]-1-Piperazinyl]-1H-Indol-5-yl] (BHAP) Acylspingosine HIV Reverse Transcriptase Inhibitors", Bioorg. Chem.23, 499-511 (1996).

320.  R. T. Borchardt, "Physicochemical and Biochemical Factors that Influence the Oral Delivery of Peptide Mimetics" in Peptides: Chemistry, Structure and Biology (Kaumaya, P. T. P. and Hodges, R. S., Eds.), Escom Science Publishers, B. V. Leiden, The Netherlands, pp. 902-904, 1996.

321.  B. Wang, M. Nicolaou, S. Liu and R. T. Borchardt, "Structural Analyses of a Facile Lactonization System Facilitated by a Trimethyl Lock", Bioorg. Chem.24, 39-49 (1996).

322.  G. M. Pauletti, S. Gangwar, G. T. Knipp, M. N. Nerurkar, F. W. Okumu, K. Tamura, T. J. Siahaan and R. T. Borchardt, "Structural Requirements for Intestinal Absorption of Peptide Drugs", J. Controlled Release41, 3-17 (1996).

323.  W. Wang, M. J. Merrill and R. T. Borchardt, "Vascular Endothelial Growth Factor Affects the Permeability of Brain Microvessel Endothelial Cells In Vitro",

          Amer. J. Physiol.271, C1973-C1980 (1996).

324.  M. G. Nicolaou, J. L. Wolfe, R. L. Schowen and R. T. Borchardt, "Facilitated Intramolecular Conjugate Addition of Amides of 3-(3',6'-Dioxo-2',4'-Dimethyl-1',4'-Cyclohexadiene) 3,3-Dimethylpropionic Acid. II. Kinetics of Degradation", J. Org. Chem.61, 6633-6638 (1996).

325.  K. Tamura, C. P. Lee, P. L. Smith and R. T. Borchardt, "Effect of Charge on the Oligopeptide Transporter-Mediated Permeation of Cyclic Dipeptides Across Caco-2 Cell Monolayers", Pharmaceutical Res.,13, 1752-1754 (1996).

326.  R. A. Conradi, P. S. Burton and R. T. Borchardt, "Physicochemical and Biological Factors that Influence a Drug's Cellular Permeability by Passive Diffusion" in Lipophilicity in Drug Action and Toxicity (V. Pliska, B. Testa and H. Vande Waterbeend, Eds.), VCH Weinheim, Weinheim, pp. 233-252, 1996.

327.  S. Liu, B. Wang, M. G. Nicolaou and R. T. Borchardt, "Trimethyl Lock Facilitated Spirocyclizations: A Structural Analysis", J. Chem. Crystallography26, 209-214 (1996).

328.  R. T. Borchardt, "Rational Design of Peptides with Enhanced Membrane Permeability”,  in”Medicinal Chemistry Today and Tomorrow”" (M. Yamazaki, Ed.), Blackwell Science, Oxford, pp. 191-196 (1996).

329.  S. Li, T. Patapoff, D. Overcashier, T. H. Nguyen and R. T. Borchardt, "Effects of Reducing Sugars on the Chemical Stability of Human Relaxin in the Lyophilized State", J. Pharm. Sci.85, 873-877 (1996).

330.  S. Li, T. Patapoff, T. H. Nguyen and R. T. Borchardt, "Inhibitory Effect of Sugars and Polyols on the Metal-Catalyzed Oxidation of Human Relaxin", J. Pharm. Sci., 85, 868-872  (1996).

331.  R. T. Borchardt, G. Wilson and P. Smith, "General Principles in the Characterization and Use of Model Systems for Biopharmaceutical Assessment" in Model Systems Used for Biopharmaceutical Assessment of Drug Absorption and Metabolism (R. T. Borchardt, G. Wilson, P. Smith, Eds.), Plenum Press, New York, 1-11, 1996.

332.  K. Audus, L. Ng, W. Wang and R. T. Borchardt, "Brain Microvessel Endothelial Cell Culture Systems" in Model Systems Used for Biopharmaceutical Assessment of Drug Absorption and Metabolism (R. T. Borchardt, G. Wilson, P. Smith, Eds.), Plenum Press, New York, 239-258, 1996.

333.  P. S. Burton, R. A. Conradi, N. F. H. Ho, A. R. Hilgers and R. T. Borchardt, "How Structural Features Influence the Permeability of Peptides", J. Pharm. Sci.,  85, 1336-1340 (1996).

334.  M. Xie, R. T. Borchardt, D. Vander Velde, M. Morton and R. L. Schowen, "pH-Induced Change in the Rate-Determining Step for the Hydrolysis of the Asp/Asn-Derived Cyclic Imide Intermediate in Protein Degradation", J. Amer. Chem. Soc.118, 8955-8956 (1996).

335.  M. M. Nerurkar, P. S. Burton and R. T. Borchardt, "The Use of Surfactants to Enhance the Permeability of Peptides Through Caco-2 Cells by Inhibition of an Apically Polarized Efflux System", Pharmaceutical Res.,  13, 528-534 (1996).

336.  S. Liu, C. S. Yuan and R. T. Borchardt, "Aristeromycin 5'-Carboxaldehyde: A Potent Inhibitor of S-Adenosyl-L-homocysteine Hydrolase", J. Med. Chem.39, 2347-2353 (1996).

337.  S. Gangwar, S. D. S. Jois, T. J. Siahaan, D. G. Vander Velde, V. J. Stella and R. T. Borchardt, “The Effect of Conformation on Membrane Permeability of an Acyloxyalkoxy-linked Cyclic Prodrug of a Model Hexapeptide", Pharmaceutical Res.13, 1657-1662 (1996).

338.  S. F. Wnuk, S. Liu, C. S. Yuan, R. T. Borchardt and M. J. Robins, "Inactivation of S-Adenosyl-L-homocysteine Hydrolase by Amide and Ester Derivatives of Adenosine 5'-Carboxylic Acid", J. Med. Chem.39, 4162-4166 (1996).

339.  K. Tamura, P. K. Bhatnagar, J. S. Takata, C. P. Lee, P. L. Smith and R. T. Borchardt, "Metabolism, Uptake and Transepithelial Transport of the Diastereomers of Val-Val in the Human Intestinal Cell Line, Caco-2", Pharmaceutical Res.,  13, 1213-1218 (1996).

340.  K. Tamura, C. P. Lee, P. L. Smith and R. T. Borchardt, "Metabolism, Uptake and Transepithelial Transport of the Stereoisomers of Val-Val-Val in the Human Intestinal Cell Line, Caco-2", Pharmaceutical Res., 13, 1663-1667 (1996).

341.  R. T. Borchardt, “Chair Report of the Research and Graduate Affairs Committee”, Amer. J. Pharm. Educ., 60, 285-225 (1996).

342.  M. Nicolaou and R. T. Borchardt, "Phosphate Prodrugs of Amines Which Utilize a Fast Hydroxy Amide Lactonization", J. Org. Chem.61, 8636-8641 (1996).

343.  C. S. Yuan, D. B. Ault-Riche and R. T. Borchardt, "Chemical Modification and Site-Directed Mutagenesis of Cysteine Residues in Human Placental S-Adenosylhomocysteine Hydrolase", J. Biol. Chem.,  271, 28009-28016 (1996).

344.  G. M. Pauletti, S. Gangwar, F. W. Okumu, T. J. Siahaan, D. G. Vander Velde, V. J. Stella and R. T. Borchardt, "Esterase-sensitive Cyclic Prodrugs of Peptides: Evaluation of an Acyloxyalkoxy Pro-moiety in a Model Hexapeptide", Pharmaceutical Res., 13, 1615-1623 (1996).

345.  L. Kupczyk-Subotkowska, K. Tamura, D. Pal, T. Sakaeda, T. J. Siahaan, V. J. Stella and R. T. Borchardt, "Melphalan Analogs and Prodrugs Designed to Enhance Accumulation in Cancer Cells", J. Drug Targeting.4, 359-370 (1997).

346.  G. M. Pauletti, S. Gangwar, B. Wang and R. T. Borchardt, "Esterase-sensitive Cyclic Prodrugs of Peptides: Evaluation of a Phenylpropionic Acid Promoiety in a Model Hexapeptide", Pharmaceutical Res., 14, 11-17 (1997).

347.  S. Gangwar, G. M. Pauletti, T. J. Siahaan, V. J. Stella and R. T. Borchardt, “Synthesis of a Novel, Esterase-Sensitive Cyclic Prodrug of a Model Hexapeptide Using an Acyloxyalkoxy Pro-moiety", J. Org. Chem.62, 1356-1362 (1997).

348.  B. Wang, S. Gangwar, G. M. Pauletti, T. J. Siahaan and R. T. Borchardt, “Synthesis of a Unique Esterase-sensitive Cyclic Prodrug System for Peptides that Utilize a “Trimethyl Lock” Facilitated Lactonization Reaction", J. Org. Chem.62, 1363-1367 (1997).

349.  F. W. Okumu, G. M. Pauletti, D. G. Vander Velde, T. J. Siahaan and R. T. Borchardt, "The Effect of Restricted Conformational Flexibility on Permeation of Model Hexapeptides Across Caco-2 Cell Monolayers", Pharmaceutical Res., 14, 169-175 (1997).

350.  G. M. Pauletti, F. W. Okumu  and R. T. Borchardt, "Effect of Size and Charge on the Passive Diffusion of Peptides Across Caco-2 Cell Monolayers via the Paracellular Pathway", Pharmaceutical Res., 14, 164-168 (1997).

351.  F. W. Okumu, J. L. Cleland and R. T. Borchardt, “The Effect of Size, Charge and Conformation of Model Peptides and a Formulation Variable on Their In Vitro Release from DL-PLGA Microspheres”, J. Controlled Release49, 133-140 (1997).

352.  S. Gangwar, G. M. Pauletti, B. Wang, T. J. Siahaan, V. J. Stella and R. T. Borchardt, “Novel Esterase-Sensitive Cyclic Prodrugs of a Model Hexapeptide Having Enhanced Membrane Permeability and Enzymatic Stability”, in Proceedings of the 14th International Symposium for Medicinal Chemistry (F. Awouters, Ed.), Elsevier Science, B.V., Amsterdam, The Netherlands, pp. 27-34 (1997).

353.  G. M. Pauletti, S. Gangwar, T. J. Siahaan, J. Aube and R. T. Borchardt, “Improvement of Oral Peptide Bioavailability: Peptide Mimetics and Prodrug Strategies”, Adv. Drug Del. Rev.27, 235-256 (1997).

354.  M. A. Turner, K. Dole, C. S. Yuan, M. S. Hershfield, R. T. Borchardt and P. L. Howell, “Crystallization and Preliminary X-Ray Analysis of Human Placental S-Adenosylhomocysteine Hydrolase”, Acta Cryst. D.D53, 339-341, 1997.

355.  R. T. Borchardt, “Are Graduate Programs Training Pharmaceutical Scientists to Function Effectively in the New, Highly Integrated and Globalized Pharmaceutical Industry?” (Editorial), Pharmaceutical Res., 14, 553-555 (1997).

356.  H. Huang, C. S. Yuan and R. T. Borchardt, “Effect of Limited Proteolysis on the Stability and Enzymatic Activity of Human Placental S-Adenosylhomocysteine Hydrolase”, Protein Science6, 1482-1490 (1997).

357.  S. Gangwar, G. M. Pauletti, B. Wang, T. J. Siahaan, V. J. Stella and R. T. Borchardt, “Prodrug Strategies to Enhance the Intestinal Absorption of Peptides”, Drug Discovery Today2, 148-155, 1997.

358. S. F. Wnuk, C. S. Yuan, R. T. Borchardt, J. Balzarini, E. De Clercq and M. J. Robins, “Anticancer and Antiviral Effects and Inactivation of S-Adenosyl-L-homocysteine Hydrolase with 5’-Carboxaldehydes and Oximes Synthesized from Adenosine and Sugar-Modified Analogues", J. Med. Chem., 40, 1608-1618 (1997).

359.  M. M. Nerurkar, N. F. H. Ho, P. S. Burton, T. J. Vidmar and R. T. Borchardt, “Mechanistic Roles of Neutral Surfactants on Concurrent Polarized and Passive Membrane Transport of a Model Peptide in Caco-2 Cells", J. Pharm. Sci.86, 813-821 (1997).

360.  C. Schöneich, M. J. Hageman and R. T. Borchardt, "Stability of Peptides and Proteins" in Controlled Drug Delivery: The Next Generation (K. Park, Ed.), ACS Books, Washington, DC, pp. 205-228 (1997).

361.  M. M. Nerurkar, M. J. Rose, J. F. Stobaugh and R. T. Borchardt, "Selective Fluorogenic Derivatization of Peptide Nucleic Acid Trimer with Naphthalene-2,3-dicaraboxaldehyde", J. Pharm. Biomed. Anal., 15, 945-950 (1997).

362.  H. Huang, C. S. Yuan, S. F. Wnuk, M. J. Robins and R. T. Borchardt, "The Mechanisms of Inactivation of Human Placental S-Adenosylhomocysteine (AdoHcy) Hydrolase by (E)-4',5'-Didehydro-5'-Deoxy-5'-Methoxyadenosine (EDDMA) and Adenosine 5'-Carboxaldehyde Oxime (ACAO)", Arch. Biochem. Biophys.,  343, 109-117 (1997).

363.  K. Tamura, K. A. Agrios, D. Vander Velde, J. Aube and R. T. Borchardt,  “Effect of Stereochemistry on the Transport of Aca-Linked b-Turn Peptidomimetics Across a Human Intestinal Cell Line”, Bioorg. Med. Chem.,  5, 1859-1866 (1997).

364.  G. T. Knipp, N. F. H. Ho, C. L. Barsuhn and R. T. Borchardt, “Paracellular Diffusion in Caco-2 Cell Monolayers: Effect of Perturbants on the Transport of Hydrophilic Compounds Which Vary in Charge and Size", J. Pharm. Sci.,  86, 1105-1110 (1997).

365.  G. T. Knipp, D. Vander Velde, T. J. Siahaan and R. T. Borchardt, “The Effect of b-Turn Structure on the Permeation of Peptides Across Caco-2 Cell Monolayers”, Pharmaceutical Res.14, 1332-1340 (1997).

366.  M. Sorensen, B. Steenberg, G. Knipp, W. Wang, B. Steffansen, S. Frokjaer and R. T. Borchardt, “The Effect of b-Turn Structure on the Permeation of Peptides Across Monolayers of Bovine Brain Microvessel Endothelial Cells”, Pharmaceutical Res., 14, 1341-1348 (1997).

367.  D. Shan, M. G. Nicolaou, R. T. Borchardt and B. Wang, “Prodrug Strategies Based on Intramolecular Cyclization Reactions”, J. Pharm. Sci.86, 765-767 (1997).

368.  R. T. Borchardt, “Task Force Report:  Value of the Pharmaceutical Sciences”, Pharmaceutical Res., 14, 958-966 (1997).

369.  A. Capdevila, R. T. Borchardt and C. Wagner, “Exocrine Secretion in Pancreatic Cells is Blocked by Prenyl Inhibitors of G-Protein Methylation”, Arch. Biochem. Biophys.345, 47-55 (1997).

370.  P. Artursson and R. T. Borchardt, “Intestinal Drug Absorption and Metabolism in Cell Culture: Caco-2 and Beyond”, Pharmaceutical Res., 14, 1655-1658 (1997).

371.  J. Li, K. Tamura, C. P. Lee, P. Smith, R. T. Borchardt and I. J. Hidalgo, “Structure-Affinity Relationships of Val-Val and Val-Val-Val Stereoisomers with the Apical Oligopeptide Transporter in the Human Intestinal Caco-2 Cells”, J. Drug Targeting,  5, 317-327 (1998).

372.  S. F. Wnuk, C. S. Yuan, R. T. Borchardt and M. J. Robins, “Nucleic Acid Related Compounds. Synthesis of Homologated Halovinyl Derivatives from Aristeromycin and Their Inhibition of Human Placental S-Adenosyl-L-Homocysteine Hydrolase”, Nucleosides and Nucleotides17, 99-113 (1998).

373.  K. L. Audus, J. Rose, W. Wang and R. T. Borchardt, "Brain Microvessel Endothelial Cell Culture Systems" in An Introduction to the Blood-Brain Barrier: Methodology, Biology and Pathology (W. M. Pardridge, Ed.), Cambridge University Press, pp. 86-93 (1998).

374.  S. Gangwar, G. M. Pauletti, T. J. Siahaan, V. J. Stella and R. T. Borchardt, “Synthesis of an Esterase-Sensitive Cyclic Prodrug of a Model Hexapeptide Having Enhanced Membrane Permeability and Enzymatic Stability Using an Acyloxyalkoxycarbamate Promoiety”, in Peptidomimetic Protocols (W. M. Kazmierski, Ed.), The Humana Press,  Totowa, NJ, pp. 37-52, 1998.

375.  B. Wang, S. Gangwar, G. M. Pauletti, T. J. Siahaan and R. T. Borchardt, “Synthesis of an Esterase-Sensitive Cyclic Prodrug of a Model Hexapeptide Having Enhanced Membrane and Enzymatic Stability Using a 3-(2’-Hydroxy-4’,6’-dimethylphenyl)-2,2-dimethylpropionic Acid Promoiety”, in Peptidomimetic Protocols(W. M. Kazmierski, Ed.), The Humana Press, Totowa, NJ, pp. 53-69, 1998.

376.  B. Wang, H. Zhang, W. Wang, D. Shan, O. Gudmundsson and R. T. Borchardt, “Synthesis of Coumarin-Based, Esterase-Sensitive Cyclic Prodrugs of Opioid Peptides with Enhanced Membrane Permeability and Enzymatic Stability”, in Peptidomimetic Protocols (W. M. Kazmierski, Ed.), The Humana Press, Totowa, NJ, pp. 71-85, 1998.

377.  M. J. Robins, S. F. Wnuk, X. Yang, C. S. Yuan, R. T. Borchardt, J. Balzarini and E. DeClercq, “Inactivation of S-Adenosylhomocysteine Hydrolase and Antiviral Activity with 5’,5’,6’,6’-Tetradehydro-6’-Deoxy-6’-Halohomoadenosine Analogues (4’-Haloacetylene Analogues Derived from Adenosine)”, J. Med. Chem., 41, 3857-3864 (1998).

378.  S. F. Wnuk, Y. Mao, C. S. Yuan, R. T. Borchardt, G. Andrei, J. Balzarinai, E. De Clercq and M. J. Robins, “Discovery of Type II (Covalent) Inactivation of S-Adenosyl-L-homocysteine Hydrolase.  Syntheses and Evaluation of Dihalohomovinyl Nucleoside Analogues Derived from Adenosine”, J. Med. Chem., 41, 3078-3083 (1998).

379.  C. S. Yuan, S. F. Wnuk, M. J. Robins and R. T. Borchardt, “A Novel Mechanism-Based Inhibitor (6’-Bromo-5’,6’-didehydro-6’-deoxy-6’-Fluorohomoadenosine) that Covalently Modifies Human Placental S-Adenosylhomocysteine Hydrolase”, J. Biol. Chem., 273, 18191-18197 (1998).

380.  M. J. Robins, V. Neschadimenko, B. O. Ro, C. S. Yuan, R. T. Borchardt and S. F. Wnuk, “Nucleic Acid Related Compounds.  101 S-Adenosyl-L-homocysteine Hydrolase Does Not Hydrate (5’-Fluoro)vinyl or (6’-Halo)homovinyl Analogues Derived from 3’-Deoxyadenosine or 4’-(Chloro or Fluoro) 3’-Deoxyadenosine”, J. Org. Chem.63, 1205-1211 (1998).

381.  R. T. Borchardt, “AAPS Task Force Report.  Value of the Pharmaceutical Sciences”, J. Pharm. Biomed. Anal.16, 1387-1401 (1998).

382.  C. Goolcharran and R. T. Borchardt, “Kinetics of Diketopiperazine Formation Using Model Peptides”, J. Pharm. Sci.87, 283-288 (1998).

383.  O. S. Gudmundsson, A. Bak, W. Wang, D. Shan, H. Zhang, G. J. Friis, B. Wang and R. T. Borchardt, “Prodrug Strategies to Enhance the Permeation of Opioid Peptides Through the Intestinal Mucosa” in Peptide and Protein Drug Delivery (S. Frokjaer, L. Christrue and P. Krogsgaard-Larsen, Eds.), Munksgaard, Denmark, pp. 259-269 (1998).

384.  M. Sudoh, G. M. Pauletti, W. Yao, P. A. Sprengeler, A. B. Smith, III, R. Hirschmann and R. T. Borchardt, “Transport Characteristics of Peptidomimetics. Effect of the Pyrrolinone Bioisostere on Transport Across Caco-2 Cell Monolayers”, Pharmaceutical Res., 15, 719-725 (1998).

385.  M. A. Turner, C. S. Yuan, R. T. Borchardt, M. S. Hershfield, G. D. Smith and P. L. Howell, “Structure of Human Placental S-Adenosylhomocysteine Hydrolase: Determination of a 30 Selenium Atom Structure”, Nature Struct. Biol.5, 369-376 (1998).

386.  G. P. Camenisch, W. Wang, B. Wang and R. T. Borchardt, “A Comparison of the Bioconversion Rates and the Caco-2 Cell Permeation Characteristics of Coumarin-Based Cyclic Prodrugs and Methylester-Based Linear Prodrugs of RGD Peptidomimetics”, Pharmaceutical Res.15, 1174-1181 (1998).

387.   M. Khossravi and R. T. Borchardt, “Chemistry of Peptide Degradation. IX. Metal-Catalyzed Oxidation of Histidine in Model Peptides: Nature of the Reactive Oxygen Species”, Pharmaceutical Res., 15, 1096-1102 (1998).

388.  O. S. Gudmundsson, G. M. Pauletti, W. Wang, D. Shen, H. Zhang, B. Wang and R. T. Borchardt, “Coumarinic Acid-based Cyclic Prodrugs of Opioid Peptides that Exhibit Increased Metabolic Stability and Enhanced Cellular Permeability”, Pharmaceutical Res.16, 7-15 (1999).

389.  O. S. Gudmundsson, K. Nimkar, S. Gangwar and R. T. Borchardt, “Phenylpropionic Acid-based Cyclic Prodrugs of Opioid Peptides that Exhibit Metabolic Stability to Peptidases and Excellent Cellular Permeation”, Pharmaceutical Res.16, 16-23 (1999).

390.  A. Bak, O. S. Gudmundsson, G. J. Friis and R. T. Borchardt, “Acyloxyalkoxy-based Cyclic Prodrugs of Opioid Peptides: Evaluation of Their Chemical and Enzymatic Stability as Well as Their Transport Properties Across Caco-2 Cell Monolayers”, Pharmaceutical Res.16, 24-29 (1999).

391.  B. Wang, K. Nimkar, W. Wang, H. Zhang , D. Shan, O. S. Gudmundsson, S. Gangwar, T. J. Siahaan and R. T. Borchardt, “Synthesis and Evaluation of the Physicochemical Properties of Esterase-sensitive Cyclic Prodrugs of Opioid Peptides Using Phenylpropionic Acid and Coumarinic Acid Linkers”, J. Peptide Res.53, 370-382 (1999).

392.  A. Bak, O. S. Gudmundsson, T. J. Siahaan, G. J. Friis and R. T. Borchardt, “Syntheses and Physicochemical Evaluation of Esterase-Sensitive Cyclic Prodrugs of Opioid Peptides Using an Acyloxyalkoxy Linker”, J. Peptide Res.53, 393-402 (1999).

393.  O. S. Gudmundsson, S.D. S. Jois, D. G. Vander Velde, T. J. Siahaan, B. Wang and R. T. Borchardt, “The Effect of Conformation on the Membrane Permeation of Coumarinic- and Phenylpropionic Acid-based Cyclic Prodrugs of Opioid Peptides”, J. Peptide Res.53, 383-392 (1999).

394.  O. S. Gudmundsson, D. G. Vander Velde, S. D. S. Jois, A. Bak, T. J. Siahaan and R. T. Borchardt, “The Effect of Conformation of Acyloxyalkoxy-based Cyclic Prodrugs of Opioid Peptides on Their Membrane Permeation”, J. Peptide Res.53, 403-413 (1999).

395.  B. Wang, W. Wang, G. P. Camenisch, J. Elmo, H. Zhang and R. T. Borchardt, “Synthesis and Evaluation of Novel Esterase-Sensitive Cyclic Prodrugs of Peptidomimetics RGD Analogs with Improved Membrane Permeability”, Chem. Pharm. Bull.,  47, 90-95 (1999).

396.  R. T. Borchardt, “Optimizing Oral Absorption of Peptides Using Prodrug Strategies”, J. Controlled Release62, 231-238 (1999).

397.  C. Goolcharran, M. Khossravi and R. T. Borchardt, “Chemical Stability of Peptides and Proteins” in Pharmaceutical Formulation and Development of Peptides and Proteins (S. Frokjaer and L. Hovgaard, Eds.), Taylor & Frances, London, pp. 70-88, 1999.

398.  N. F. Ho, T. R. Raub, P. S. Burton, C. L. Barsuhn, A. Adson, K. L. Audus and R. T. Borchardt, "Quantitative Approaches to Delineate Transport Mechanisms in Cell Culture Monolayers", in Transport Processes in Pharmaceutical Systems (K. J. Himmelstein, G. L. Amidon and P. I. Lee, Eds.), Marcel Dekker, Inc., New York, pp. 219-316, 1999.

399.  R. T. Borchardt, “Prodrug Strategies to Enhance the Permeation of Peptides Through the Intestinal Mucosa”, in Peptides: Frontiers of Peptide Science, Proceedings of the 15th American Peptide Symposium (J. P. Tam and P. T. P. Kaumaya, Eds.), Kluwer Academic Publisher, Dordrecht, The Netherlands, pp. 825-827 (1999).

400.  M. C. Lai, M. J. Hageman, R. L. Schowen, R. T. Borchardt and E. M. Topp, “Chemical Instability of Peptides in Polymers. I. Effect of Water on Peptide Deamidation in Poly (Vinyl Alcohol) and Poly (Vinyl Pyrrolidone) Matrices”, J. Pharm. Sci.88, 1073-1080 (1999).

401.  M. C. Lai, M. J. Hageman, R. L. Schowen, R. T. Borchardt, and E. M. Topp, “Chemical Stability of Peptides in Polymers. II. Discriminating Between Solvent and Plasticizing Effects of Water on Peptide Deamidation in Poly (Vinyl Pyrrolidone)”, J. Pharm. Sci.88, 1081-1089 (1999).

402.  E. D. Hugger, B. L. Novak and R. T. Borchardt, “The Effects of Nonionic Surfactants on the Permeation of Solutes Across Caco-2 Cell Monolayers”, Bulletin Technique Gattefosse entitled Recent Advances in the Formulation and Development of Poorly-Soluble Drugs, p.  59-65 (1999).

403.  G. L. Grunewald, T. M. Caldwell, Q. Li, M. Slavica, W. Wang, R. T. Borchardt and K. R. Criscione, “Synthesis and Biochemical Evaluation of 3-fluoromethyl-1,2,3,4-tetrahydroisoquinolines as Selective Inhibitors of Phenylethanolamine N-Methyltransferase vs. the a2-Adrenoceptor”, J. Med. Chem.42, 3588-3601 (1999).

404.  C. S. Yuan, Y. Saso, E. Lazarides, R. T. Borchardt and M. J. Robins, “Recent Advances in S-Adenosyl-L-Homocysteine Hydrolase Inhibitors and Their Potential Clinical Applications”, Expert Opinions on Therapeutic Patents9, 1197-1206 (1999).

405.  R. T. Borchardt, G. Camenisch, E. Hugger, W. Wang, D. Shan, G. L. Wheeler, C. P. Cheng and B. Wang, “Prodrug Strategies to Improve the Oral Absorption of Peptide Mimetics”, Polymer Preparations40, 257-258 (1999).

406.  S. F. Wnuk, C. S. Yuan, R. T. Borchardt and M. Robins, “Design and Biological Evaluatioan of New Mechanism-based Inhibitors of S-Adenosyl-L-homocysteine Hydrolase”, Nucleoside Nucleotides18, 595-596 (1999).

407.  D. Shan, A. Zheng, C. E. Ballard, W. Wang, R. T. Borchardt and B. Wang, “Facilitated Cyclic Ether Formation and Its Potential Application in Peptide and Organic Synthesis”, Chem. Pharm. Bull.48, 238-244, 2000.

408.  M. C. Lai, R. L. Schowen, R. T. Borchardt and E. M. Topp, “Deamidation of a Model Hexapeptide in Poly(Vinyl Alcohol) Hydrogels and Xerogels”, J. Peptide Res.55, 93-101 (2000).

409.  W. Wang, G. Camenisch, D. C. Sane, H. Zhang, E. Hugger, G. L. Wheeler, R. T. Borchardt and B. Wang, “A Coumarin-Based Prodrug Strategy to Improve the Oral Absorption of RGD Peptidomimetics”, J. Controlled Release65, 245-251 (2000).

410.  D. Yin, X. Yang, C. S. Yuan and R. T. Borchardt, “Mechanism-Based S-Adenosyl-L-Homocysteine Hydrolase Inhibitors in the Search for Broad-Spectrum Antiviral Agents”, in Biomedical Chemistry: Applying Chemical Principles to the Understanding and Treatment of Disease (P. F. Torrence, Ed.), John Wiley & Sons, Inc., New York, p. 41-71 (2000).

411.  R. T. Borchardt and B. Wang, “Prodrug Strategies to Improve the Oral Absorption of Peptides and Peptide Mimetics”, in Drug Delivery in the 21st Century, ACS Books, Washington, DC, pp. 36-45 (2000).

412.  J. Gao, E. Hugger, M. Beck-Westermeyer and R. T. Borchardt, “Protocols for the Application of Caco-2 Cells in Measuring Permeability Coefficients of Drugs”, Current Protocols in Pharmacology, 7.2.1-7.2.23 (2000).

413.  W. Wang, R. T. Borchardt and B. Wang, “Orally Active Peptidomimetic RGD Analogs That Are Glycoprotein IIb/IIIa Antagonists”, Current Medicinal Chemistry7, 437-453 (2000).

414.  W. Wang, R. T. Borchardt, D. Sane and B. Wang, “Delivering Peptides and Peptidomimetics Across Membrane Barriers. A Prodrug Approach”, in Peptides for the New Millennium (G. B. Fields, J. P. Tam and G. Barany, Eds.), Kluwer Academic Publisher, Netherlands, 214-216, 2000.

415.  M. Khossravi and R. T. Borchardt, “Chemical Pathways of Peptide Degradation X.  Effect of Metal-Catalyzed Oxidation on the Solution Structure of a Histidine-Containing Peptide Fragment of Human Relaxin”, Pharmaceutical Res., 17, 851-858 (2000).

416.  M. Khossravi, S. J. Shire and R. T. Borchardt, “Evidence for the Involvement of Histidine A(12) in the Aggregation and Precipitation of Human Relaxin Induced by Metal Catalyzed Oxidation”, Biochemistry39, 5876-5885 (2000).

417.  C. Goolcharran, J. L. Cleland and R. T. Borchardt, “The Effects of a Histidine Residue on the C-Terminal Side of an Asparaginyl Residue on the Rate of Deamidation Using Model Pentapeptides”, J. Pharm. Sci.89, 818-825 (2000).

418.  C. Goolcharran, J. L. Cleland, R. Keck, A. J. S. Jones and R. T. Borchardt, “A Comparison of the Rate of Deamidation and Diketopiperazine Formation in Recombinant Human Vascular Endothelial Cell Growth Factor (rhVEGF) and Model Peptide Fragments of VEGF”, AAPSPharm.Sci., 2 (1) article 5 (2000) (http://www.pharmsci.org/).

419.  S. F. Wnuk, C. A. Valdez, J. Khan, P. Moutinho, M. J. Robins, X. Yang, R. T. Borchardt and E. DeClercq, “Doubly Homologated Dihalovinyl and Acetylene Analogues of Adenosine: Synthesis, Interaction with S-Adenosyl-L-homocysteine Hydrolase and Antiviral and Cytostatic Effects”, J. Med. Chem.43, 1180-1186 (2000).

420.  M. Xie, J. Aube, R. T. Borchardt, M. Morton, E. M. Topp, D. Vander Velde and R. L. Schowen, “Reactivity Toward Deamidation of Asparagine Residues in b-Turn Structures”, J. Peptide Res., 56, 165-171 (2000).

421.  X. Yang, D. Yin, S. F. Wnuk, M. J. Robins and R. T. Borchardt, “Mechanism of Inactivation of Human S-Adenosylhomocysteine Hydrolase by 5¢,5¢,6¢,6¢-Tetrahydro-6¢-Deoxy-6¢-Halohomoadenosine Analogues”, Biochemistry39, 15234-15241 (2000).

422.  X. Yang and R. T. Borchardt, “Overexpression, Purification and Characterization of S-Adenosylhomocysteine Hydrolase from Leishmania Donovani”, Arch. Biochem. Biophys.383, 272-280 (2000).

423.  R. T. Borchardt, “Training Grants in the Chemical and Biological Sciences” in Graduate Education in the Chemical Sciences: Issues for the 21st Century, National Research Council, Washington, DC, 144-158 (2000).

424.  R. Li, B. B. Laird, R. L. Schowen, R. T. Borchardt and E. M. Topp, “Effect of Solution Polarity and Viscosity on Peptide Deamidation”, J. Peptide Res., 56, 326-334 (2000).

425.  D. Yin, X. Yang, Y. Hu, K. Kuczera, R. L. Schowen, R. T. Borchardt and T. C. Squier, “Substrate Binding Induces Global Conformational Changes Within S-Adenosylhomocysteine Hydrolase”, Biochemistry39, 9811-9818 (2000).

426.  W. Wang, W. L. Dentler and R. T. Borchardt, “Vascular Endothelial Growth Factor Increases the Permeability of Brain Microvessel Endothelial Cell Monolayers by Affecting Tight Junction Assembly”, Amer. J. Physiol.:  Heart and Circulatory Physiology, 280, H434-H440 (2001).

427.  M. A. Turner, X. Yang, D. Yin, K. Kuczera, R. T. Borchardt and P. L. Howell, “Structure and Function of S-Adenosylhomocysteine Hydrolase”, Cell Biochem. Biophys.33, 101-125 (2001).

428.  Y. Song, R. L. Schowen, R. T. Borchardt and E. M. Topp, “Effect of pH on the Rate of Asparagine Deamidation in Polymeric Formulations: ‘pH’-Rate Profile, J. Pharm. Sci.90, 141-156 (2001).

429.  R. T. Borchardt, “Biological Models to Assess Drug Bioavailability”, in Pharmacokinetic Optimization in Drug Research: Biological, Physicochemical and Computational Strategies (B. Testa, H. vande Waterbeemd, G. Folkers and R. Guy, Eds.), Wiley-VHCA, Zurich,  117-126, 2001.

430.  Y. Song, R. L. Schowen, R. T. Borchardt and E. M. Topp, “Formaldehyde Production by Tris Buffer in Peptide Formulations at Elevated Temperatures”, J. Pharm. Sci., 90, 1198-1203 (2001).

431.  J. Gao, O. Murase, R. L. Schowen, J. Aube and R. T. Borchardt, “A Functional Assay for Quantitation of the Apparent Affinities of Ligands of P-Glycoprotein in Caco-2 Cells”, Pharm. Res.18, 171-176(2001).

432.  J. Gao, M. Sudoh, J. Aube and R. T. Borchardt, “Transport Characteristics of Peptides and Peptidomimetics: 1 N-Methylated Peptides as Substrates for the Oligopeptide Transporter and P-Glycoprotein in the Intestinal Mucosa”, J. Peptide Res., 57, 316-329 (2001).

433.  J. Gao, S. L. Winslow, D. Vander Velde, J. Aube and R. T. Borchardt, “Transport Characteristics of Peptides and Peptidomimetics: 2. Hydroxyethyamine Bioisostere-Containing Peptidomimetics as Substrates for the Oligopeptide Transporter and P-Glycoprotein in the Intestinal Mucosa”, J. Peptide Res.57, 361-373 (2001).

434.  R. T. Borchardt, “Integrating Drug Discovery and Development: A Major Challenge for the Pharmaceutical Industry” (Invited Commentary), The Scientist15, 43-45 (2001).

435.  Y. Hu, X. Yang, D. H. Yin, J. Madadevan, K. Kuczera, R. L. Schowen and R. T. Borchardt, “Computational Characterization of the Substrate Binding and Catalysis in S-Adenosylhomocysteine Hydrolase”, Biochemistry40, 15143-15152 (2001).

436.  F. Tang and R. T. Borchardt, “Are MDCK Cells Transfected with the Human MDR1 Gene a Good Model of the Human Intestinal Mucosa?”, Pharm. Res.19, 765-772 (2002).

437.  F. Tang, K. Horie and R. T. Borchardt, “Are MDCK Cells Transfected with the Human MRP2 Gene a Good Model of the Human Intestinal Mucosa?”, Pharm. Res.19, 773-779 (2002).

438.  H. Ouyang, F. Tang, T. J. Siahaan and R. T. Borchardt, “A Modified Coumarinic Acid-based Cyclic Prodrug of an Opioid Peptide: Enzymatic and Chemical Stability and Membrane Permeation Characteristics”, Pharm. Res.19, 794-801 (2002).

439.  H. Ouyang, D. Vander Velde, R. T. Borchardt and T. J. Siahaan, “Synthesis and Conformational Analysis of a Coumarinic Acid-based Cyclic Prodrug of an Opioid Peptide with Modified Sensitivity to Esterase-catalyzed Bioconversion”, J. Peptide Res.59, 183-195 (2002).

440.  F. Tang and R. T. Borchardt, “Characterization of the Efflux Transporter(s) Responsible for Restricting Mucosa Intestinal Mucosa Permeation of an Acyloxyalkoxy-based Cyclic Prodrug of the Opioid Peptide DADLE”, Pharm. Res.19, 780-786 (2002).

441.  F. Tang and R. T. Borchardt, “Characterization of the Efflux Transporter(s) Responsible for Restricting Intestinal Mucosa Permeation of the Coumarinic Acid-based Cyclic Prodrug of the Opioid Peptide DADLE”, Pharm. Res.19, 787-793 (2002). 

442.  H. Ouyang, R. T. Borchardt and T. J. Siahaan, “Steric Hindrance is a Key Factor in the Coupling Reaction of (Acyloxy)Alkyl-a-halides with Phenols”, Tetrahedron Letters43, 577-579 (2002).

443.  E. D. Hugger, B. L. Novak, P. S. Burton, K. L. Audus and R. T. Borchardt, “A Comparison of Commonly Used Polyethoxylated Pharmaceutical Excipients on Their Ability to Inhibit P-Glycoprotein Activity In Vitro”, J. Pharm. Sci.91, 1991-2002 (2002).

444.  W-Q. Chen, F. Tang, K. Horie and R. T. Borchardt, “Caco-2 Cell Monolayers as a Model for Studies of Drug Transport Across Human Intestinal Epithelium” in Cell Culture Models of Biological Barriers: In Vitro Test Systems for Drug Absorption and Delivery(C. M. Lehr, Ed.), Haarwood Academic Publishers, pp. 143-163 (2002).

445.  E. D. Hugger, K. L. Audus and R. T. Borchardt, “The Effects of Polyethylene Glycol on Efflux Transporter Activity in Caco-2 Cell Monolayers”, J. Pharm. Sci.91, 1980-1990 (2002).

446.  P. Elrod, J. Zhang, X. Yang, D. Yin, Y. Hu, R. L. Schowen and R. T. Borchardt, “Contribution of Active-site Residues to the Partial and Overall Catalytic Activities of Human S-Adenosylhomocysteine Hydrolase”, Biochemistry41, 8134-8142 (2002).

447.  S. F. Wnuk, Bong-Oh Ro, C. A. Valdez, E. Lewandowska, N. X. Valdez, P. R. Sacasa, D. Yin, J. Zhang, R. T. Borchardt and E. DeClercq, “Sugar-Modified Conjugated Diene Analogues of Adenosine and Uridine Synthesis, Interaction with S-Adenosyl-L-homocysteine Hydrolase and Antiviral and Cytostatic Effects”, J. Med. Chem.45, 2651-2658 (2002).

448.  J. Z. Yang, C. K. Bastian, R. D. Moore, J. F. Stobaugh and R. T. Borchardt, “Quantitative Analysis of a Model Opioid Peptide and Its Cyclic Prodrugs in Rat Plasma Using high Performance Liquid Chromatography and Fluorescence and Tandem Mass Spectrometric Detection”, J. Chromatography B780, 269-281 (2002).

449.  J. Z. Yang, W. Chen and R. T. Borchardt, “In Vitro Stabilty and In Vivo Pharmacokinetic Studies of a Model Opioid Peptide (DADLE) and Its Cyclic Prodrugs”, J. Pharmacol. Exptl. Therap., 303, 840-848 (2002).

450.  W. Chen, J. Z. Yang , R. Anderson, L. H. Nielsen and R. T. Borchardt, “Evaluation of the Permeability Characteristics of a Model Opioid Peptide (DADLE and Its Cyclic Prodrugs Across the Blood Brain Barrier Model”, J. Pharmacol. Exptl. Therap., 303, 849-857 (2002).

451.  R. W. Miles, L. P. C. Nielsen, G. J. Ewing, D. Yin, R. T. Borchardt and M. J. Robins, “S-Homoadenosyl-L-cysteine and S-Homoadenosyl-L-homocysteine.  Synthesis and Binding Studies of Non-Hydrolyzed Substrate Analogues with S-Adenosyl-L-homocysteine Hydrolase”, J. Org. Chem.67, 8258-8260 (2002).

452.  G. Friedrichsen, W-Q. Chen, M. Begtrup, Chao-Pin Lee, P. Smith and R. T. Borchardt, “Synthesis of Analogs of Valacyclovir and Determination of Their Substrate Activity for the Oligopeptide Transporter in Caco-2 Cells”, European J. Pharm. Sci.,16, 1-13 (2002).

453.  E. D. Hugger, C. J. Cole, T. J. Raub, P. S. Burton and R. T. Borchardt, “Automated Analysis of Polyethylene Glycol (PEG)-Induced Inhibition of P-Glycoprotein Activity In Vitro”, J. Pharm. Sci.92, 21-26 (2003).

454.  M. Xie, Z. Shahrokh, M. Kadkhodayan, W. J. Henzel, M. P. Powell, R. T. Borchardt and R. L. Schowen, “Asparagine Deamidation in Recombinant Human Lymphotoxin: Hindrance by Three-Dimensional Structures”, J. Pharm. Sci.92, 869-880 (2003).

455.  A.J.M. D’Souza, R. L. Schowen, R. T. Borchardt, J. S. Salsbury, E. J. Munson and E. M. Topp, “Reaction of a Peptide with Polyvinylpyrrolidone in Solid-State”, J. Pharm. Sci.92, 585-593 (2003).

456.  X. Yang, Y. Hu, D. Yin, M. A. Turner, R. T. Borchardt, L. Howell, K. Kuczera and R. L. Schowen, “Catalytic Strategy of S-Adenosyl-L-homocysteine Hydrolase: Transition State Stabilization and the Avoidance of Abortive Reactions”, Biochemistry42, 1900-1909 (2003).

457.  K. Horie, F. Tang and R. T. Borchardt, “Isolation and Characterization of Caco-2 Subclones Overexpressing the MDR1 Efflux Transport”, Pharm. Res.20, 159-166 (2003).

458.  B. M. Johnson, W. Chen, R. T. Borchardt, W. N. Charman and C. J. H. Porter, “A Kinetic Evaluation of the Absorption, Efflux and Metabolism of Verapamil in the Autoperfused Rat Jejunum”, J. Pharm. Exptl. Therap.305, 151-158 (2003).

459.  S. Wnuk, P. R. SaCasa, L. N. Crain, E. Leward, J. Zhang and R. T. Borchardt, “Stereocontrolled Synthesis of Diene and Enzyme Sugar-Modified Nucleosides and Their Interaction with S-Adenosyl-L-Homocysteine Hydrolase”, Nucleosides, Nucleotides and Nucleic Acids22, 783-785 (2003).

460.  R. T. Borchardt, Foreword in Biotechnology and Biopharmaceuticals: Transforming Proteins and Genes into Drugs(R.J.Y. Ho and M. Gibaldi, Eds.), John Wiley & Sons, Inc., New York, NY, xi-xii, 2003.

461.  B. Li, R. T. Borchardt, E. M. Topp, D. Vander Velde and R. L. Schowen, “Rapid, Specific Racemization of an Asparagine Residue During Peptide Deamidation”, J. Amer. Chem. Soc., 125, 11486-11487 (2003).

462.  N. B. Parker, D. H. Yin, K. A. Mason, J. Henke, R. L. Schowen and R. T. Borchardt, “Isolation of the Gene Encoding Trypanosoma cruzi S-Adenosylhomocysteine Hydrolase and Characterization of the Expressed Enzyme”, Experimental Parasitology, 105, 149-158 (2003).

463.  R. T. Borchardt, “Scientific, Educational and Communication Issues Associated with Integrating and Applying Drug-like Data in Drug Discovery”, in Pharmaceutical Profiling in Drug Discovery for Lead Selection”, (R. T. Borchardt et al., Eds.), AAPS Press, Arlington, VA, p. 451-466 (2004).

464.  J. Vabeno, T. Lejon, C. U. Nielsen, B. Steffansen, W. Chen, H. Ouyang, R. T. Borchardt and K. Luthman, “Phe-Gly Dipeptidomimetics Designed for the Di-/Tripeptide Transporters PET1 and PEPT2: Synthesis and Biolgoical Investigations”, J. Med. Chem.47, 1060-1069 (2004).

465.  F. Tang, J. Z. Yang and R. T. Borchardt, “Bi-directional Transport of Rhodamine 123 and Hoechst 3342, Fluorescence Probes of the Binding Sites on P-glycoprotein, Across MDCK-MDR1 Cell Monolayers”, J. Pharm. Sci., 93, 1185-1194 (2004).

466.  J. E. Polli et al., “Summary Workshop Report: Biopharmaceutics Classification System – Implementation, Challenges and Extension Opportunities”, (Commentary), J. Pharm. Sci.93, 1375-1381 (2004).

467.  C. E. Stotz, R. T. Borchardt, C. R. Middaugh, T. J. Siahaan, D. Vander Velde and E. M. Topp, “Secondary Structure of a Dynamic Type I´b -Hairpin Peptide”, J. Peptide Research63, 371-382 (2004).

468.  S. F. Wnuk, E. Lewandowska, P. R. Sacasa, L. N. Crain, J. Zhang, R. T. Borchardt and E. DeClercq, “Stereoselective Synthesis of Sugar-modified enzyme Analogues of Adenosine and Uridine.  Interaction with S-Adenosyl-L-homocysteine Hydrolase and Antiviral and Cytostatic Effects”, J. Med. Chem.47, 5251-5257 (2004).

469.   B. Li, M. O’Meara, J. W. Lubach, R. L. Schowen, E. M. Topp, E. J. Munson and R. T. Borchardt, “Effect of Sucrose and Mannitol on Asparagine Deamidation Rates in Solution and in the Solid State”, J. Pharm. Sci.94, 1723-1735 (2005).

470.  B. Li, E. Gorman, K. D. Moore, T. D. Williams, R. L. Schowen, E. M. Topp and R. T. Borchardt, “Effects of Acidic N+1 Residues on Asparagine Deamidation Rates in Solution and in the Solid State”, J. Pharm. Sci.94, 666-675 (2005).

471.  M. M. Wang, K. Kuczera, R. L. Schowen and R. T. Borchardt, “Domain Motions and the Open-to-Closed Conformational Transition of an Enzyme: A Normal Mode Analysis of S-Adenosyl-L-Homocysteine Hydrolase”, Biochemistry44, 7228-7239 (2005).

472.  S. Wnuk, M. M. Wang, J. Zhang, K. Kuczera, R. L. Schowen and R. T. Borchardt, “Are L-Adenosine and Its Derivatives Substrates for S-Adenosylhomocysteine Hydrolase?”, J. Med. Chem.48, 3649-3653 (2005).

473.  B. M. Liederer and R. T. Borchardt, "Stability of Oxymethyl-Modified Coumarinic Acid Cyclic Prodrugs of Diastereomeric Opioid Peptides in Biological Media from Various Animal Species Including Human", J. Pharm. Sci.94, 2198-2206 (2005).

474.  B. M. Liederer, K. T. Phana, H. Ouyang and R. T. Borchardt, "Significant Differences in the Disposition of Cyclic Prodrugs of Opioid Peptides in Rats and Guinea Pigs Following IV Administration",  J. Pharm. Sci.94, 2676-2687 (2005).

475.  S. L. Krogmeier, D. S. Reddy, D. Vander Velde, G. H. Lushington, T. J. Siahaan, C. R. Middaugh, R. T. Borchardt and E. M. Topp, "Deamidation of Model b-Turn Cyclic Peptides in the Solid State", J. Pharm. Sci.94, 2616-2631 (2005).

476.  R. T. Borchardt, “Educational and Communication Issues Related to Profiling Compounds for their Drug-like Properties”, in Pharmacokinetic Profiling in Drug Research (B. Testa, Ed. et al.), p. 461-465 (2006).

477.  B. M. Liederer, T. Fuchs, D. Vander Velde, T. J. Siahaan and R. T. Borchardt, “Effects of Amino Acid Chirality and the Chemical Linker on the Cell Permeation Characteristics of Cyclic Prodrugs of Opioid Peptides”, J. Med. Chem.49, 1261-1270 (2006).

478.  B. M. Liederer and R. T. Borchardt, “Enzymes Involved in the Bioconversion of Ester-Based Prodrugs", J. Pharm. Sci.95, 1177-1195 (2006).

479.   B. Li, R. L. Schowen, E. M. Topp and R. T. Borchardt, “Effect of N-1 and N-2 Residues on Peptide Deamidation Rate in Solution and Solid State”, The AAPS Journal, 8 (1) article 20 (2006) (http://www.aapsj.org).

480.  M. M. Wang, J. R. Unruh, C. K. Johnson, K. Kuczera, R. L. Schowen and R. T. Borchardt, “Efects of Ligand Binding and Oxidation on Hinge Binding in S-Adenosyl-L-homocysteine Hydrolase”, Biochemistry45, 7778-7786 (2006).

481.  A. A. Wakankar and R. T. Borchardt, “Formulation Approaches to Stabilization of Therapeutic Proteins to Asn Deamidation and Asp Isomerization’, J. Pharm. Sci., 96, 2321-2336 (2006).

482.  A. A. Wakankar, R. T. Borchardt, S. J. Shire and J. L. Liu, “The Effects of Co-solutes on Isomerization  of Aspartic Acid Residues and Conformational Stability in a Monoclonal Antibody”, J. Pharm. Sci., 96, 1708-1718 (2007).

483.  A. A. Wakankar, R. T. Borchardt, C. Eigenbrot, S. Shia, J. Y. Wang, S. J. Shire and J. L. Liu, “Aspartate Isomerization in the Complementary Determining Regions of Two Closely Related Monoclonal Antibodies”, Biochemistry46, 1534-1544 (2007).

484.  Q-S Li, S. Cai, R. T. Borchardt, J. Fang, K. Kuczera, C. R. Middaugh and R. L. Schowen, “Comparative Kinetics of Cofactor Association and Dissociation for  the Human and Trypanosomal S-Adenosylhomocysteine Hydrolases. 1. Basic Features of the Association and Dissociation Processes”, Biochemistry46, 5798-5809 (2007).

485.  S. Cai, Q-S Li, R. T. Borchardt, K. Kuczera and R. L. Schowen, “The Antiviral Drug Ribavirin is a Selective Inhibitor of S-Adenosyl-L-homocysteine Hydrolase from Trypanosoma cruzi”, Bioorganic and Medicinal Chemistry15, 781-787 (2007).

486. C. Hu, J. Fang, R. T. Borchardt, R. L. Schowen and K. Kuczera, “Molecular Dynamics Simulations of Domain Motions of Substrate Free S-Adenosylhomocystiene in  Solution”, Proteins: Structure, Function and Bioinformatics, 71, 131-143 (2008).

487. Q-S Li, S. Cai, R. T. Borchardt, J. Fang, K. Kuczera, C. R. Middaugh and R. L. Schowen, “Comparative Kinetics of Cofactor Association and Dissociation for the Human and Trypanosomal S-Adenosylhomocysteine Hydrolases.  2. The Role of Helix 18 Stability”, Biochemistry,47, 4983-4991 (2008).

488.  R. T.  Borchardt, “Drug Design with ADME in Mind; Recent Paradigm Shift in Drug Discovery”, in Proceedings of the Solvay Conference entitled Toward Drugs of the Future and Key Issues in Lead Finding and Lead Optimization”, pp 57-74, 2008.

489. S. F. Wnuk, P. R. Sacasa, E. Lewandowska, D. Andrei, S. Cai and R. T. Borchardt, “Synthesis of  5’-Functionalized Nucleosides: S-Adenosylhomocysteine Analogues with the Carbon-5’ and Sulfur Atom Replaced by a Vinyl or Halovinyl Unit”, Biorg. Med. Chem., 16, 5424-5433 (2008)

490. H. Ouyang, W. Chen, T. E. Anderson, B. Steffansen and R. T. Borchardt, "Factors that Restrict the Cell Permeation of Cyclic Prodrugs of an Opioid Peptide (DADLE): 1. The Role of Efflux Transporters in the Intestinal Mucosa”, J. Pharm. Sci., 98, 337-348 (2009)

491.  H. Ouyang, W. Chen, T. E. Anderson, B. Steffansen and R. T. Borchardt, “Factors that Restrict the Cell Permeation of Cyclic Prodrugs of an Opioid Peptide (DADLE): 2. The Role of Metabolic Enzymes in the Intestinal Mucosa, J. Pharm. Sci., 98, 349-361 (2009)

492.  H. Ouyang, T. E. Anderson, W. Chen, B. Steffansen and R. T. Borchardt, “A Comparison of the Effects of P-Glycoprotein Inhibitors on the Blood Brain Barrier Permeation of Cyclic Prodrugs of an Opioid Peptide (DADLE)”, J. Pharm. Sci., 98, 2227-2236 (2009).

493.  S. Cai, R. T. Borchardt, K. Kuczera and R. L. Schowen, “The Rational for Targeeting the NAD/NADH Cofactor Binding Site of Parasitic S-Adenosyl-L-homocysteine Hydrolase for the Design of Anti-Parasitic Drugs”, Nucleosides, Nucleotides and Nucleic Acids, 28, 485-503 (2009).

494. Q-S. Li, S. Cai,  J. Fang, R. T. Borchardt, K. Kuczera, C. R. Middaugh and R. L. Schowen, “ Evaluation of NAD(H) Analogues as Selective Inhibitors for Trypanosoma cruzi S-Adenosyl-L-homocysteine Hydrolase for the Design of Anti-Parasitic Drugs” , Nucleosides, Nucleotides and Nucleic Acids, 28, 473-484 (2009).

495. D.R. Mudra and R.T. Borchardt, “Absorption Barriers in the Rat Intestinal Mucosa: 1. Development of an In Situ Single-Pass Perfusion Model to Simultaneously Assess Drug Permeation and Metabolism”, J. Pharm. Sci., 99, 982-998 (2010).

496. D.R. Mudra, J. Y. Jin and R.T. Borchardt, “Absorption Barriers in the Rat Intestinal Mucosa: 2. Application of Physiologically Based Mathematical Models to Quantify Mechanisms of Drug Clearance”, J. Pharm. Sci., 99, 999-1015 (2010).

497. D.R. Mudra and R.T. Borchardt, “Absorption Barriers in the Rat Intestinal Mucosa: 3. Effects of Polyethoxylated Solubilizing Agents on Drug Permeation and Metabolism”, J. Pharm. Sci., 99, 1016-1027 (2010).

498. S. Cai, J. Fang, Q-S Li, R.T. Borchardt, K. Kuczera, C.R. Middaugh and R.L. Schowen, “Comparative Kinetics of Cofactor Association and Dissociation for the Human and Trypansomal S-Adenosylhomocysteine Hydrolases. 3. The Role of Lysyl and Tyrosyl Resideues of the C-Terminal Extension”, Biochemistry, 49, 8434-8441 (2010).

499.  R. T. Borchardt, “Hidalgo, I. J., Raub, T. J. and Borchardt, R. T., Characterization of the Human-Colon Carcinoma Cell-Line (Caco-2) as a Model System for Intestinal Epithelial Permeability, Gastroenterology, 96, 736-749,1989—The Backstory”, AAPS Journal, 13, 323-327, 2011.

500. R. Nofsinger, T. Fuchs-Knotts and R. T. Borchardt, “Factors that Restrict the Cell Permeation of Cyclic Prodrugs of an Opioid Peptide: 3. Synthesis of Analogs Designed to have Improved Stability to Oxidative Metabolism”, J. Pharm. Sci., 101, 3486-3499 (2012)

Awards & Honors

  • Established Investigator, American Heart Association (1974-1979)
  • Sato Memorial International Award, Pharmaceutical Society of Japan (1981)
  • Mortar Board Outstanding Educator Award (1980)
  • Dolph C. Simons, Sr. Research Award in the Biomedical Sciences (1983)
  • Louise Byrd Graduate Educator Award (1997)
  • Chancellor's Club Career Teaching Award, University of Kansas (2005)
  • Fellow, American Association of Pharmaceutical Scientists (1988)
  • Fellow, American Association for the Advancement of Science (1995)
  • Citation of Merit, University of Wisconsin (1989)
  • Meritorious Manuscript Awards (1991, 1998)
  • Research Achievement Awards in Biotechnology (1993) 
  • Research Achievement Awards in Medicinal Chemistry (1994)
  • Distinguished Pharmaceutical Scientist Award, American Association of Pharmaceutical Scientists (1997)
  • Takeru and Aya Higuchi Memorial Lectureship Award, Academy of Pharmaceutical Sciences and Technology of Japan (1993)
  • Paul Dawson Biotechnology Award (1997)
  • Volwiler Research Achievement Award, American Association of Colleges of Pharmacy (1998)
  • Hoest-Madsen Medal, International Pharmaceutical Federation (1999)
  • Distinguished Service Award, FASEB Research Conference on Biological Methylation (1999
  • Millennial Pharmaceutical Scientist Award, Millennial World Congress of Pharmaceutical Sciences (2000)
  • Research Achievement Award in the Pharmaceutical Sciences (2001)
  • Takeru Higuchi Research Prize, American Pharmaceutical Association (2003)
  • Smissman-Bristol-Myers Squibb Award, Medicinal Chemistry Division of the American Chemical Society (2003)
  • PolyPops Foundation Award, Society for Biomolecular Sciences (2007)
  • Honorary Doctorate Degrees, Danish University of Pharmaceutical Sciences, Copenhagen, Denmark (2002), Katholieke University, Leuven, Belgium (2004) and Uppsala University, Uppsala, Sweden (2006)