Abstract
A fundamental knowledge of applied organic chemistry is an important weapon in the arsenal of drug metabolism scientists, particularly ones engaged in the design and/or the conduct of biotransformation studies or as drug hunters. Application of basic organic chemistry concepts (e.g., nucleophilicity/electrophilicity, bond polarity, electron flow, etc.) are important in elucidating structures of complex metabolites, arising from the metabolism of xenobiotics, and rationalizing the biotransformation mechanisms leading to their formation. An appreciation for the art of using mechanistic chemistry insights to study metabolic processes is usually gained during graduate training (MS and/or PhD) in academic laboratories specialized in the fields of chemical toxicology, medicinal chemistry, and/or enzymology. Select examples of academic research efforts, wherein mechanistic organic chemistry concepts were successfully applied to rationalize and establish structure-metabolism toxicology relationship trends for the oxidative metabolism of alicyclic amines are highlighted in this manuscript. The co-authors of this manuscript participated in some of this research work during their academic training, and went on toward a career in the pharmaceutical industry, where they applied their academic training toward studies on the metabolism of new drug substances, which also included efforts exploring the chemical basis for a toxicological consequence(s) in the preclinical discovery setting. The latter attribute is highlighted with a case study exploring metabolic activation pathways with a small molecule 5-HT2C agonist, which was genotoxic in the in vitro Ames assay.
Similar content being viewed by others
References
Kramlinger VM, Dalvie D, Heck CJS, Kalgutkar AS, O’Neill J, Su D, et al. Future of Biotransformation Science in the Pharmaceutical Industry. Drug Metab Dispos. 2022;50:258–67. https://doi.org/10.1124/dmd.121.000658
MacCoss M, Baillie TA. Organic chemistry in drug discovery. Science. 2004;303:1810–3. https://doi.org/10.1126/science.1096800
Cerny MA, Kalgutkar AS, Obach RS, Sharma R, Spracklin DK, Walker GS. Effective Application of Metabolite Profiling in Drug Design and Discovery. J Med Chem. 2020;63:6387–406. https://doi.org/10.1021/acs.jmedchem.9b01840
Kalgutkar AS. Designing around Structural Alerts in Drug Discovery. J Med Chem. 2020;63:6276–302. https://doi.org/10.1021/acs.jmedchem.9b00917
Obach RS. Pharmacologically active drug metabolites: impact on drug discovery and pharmacotherapy. Pharm Rev. 2013;65:578–640. https://doi.org/10.1124/pr.111.005439
Penner N, Klunk LJ, Prakash C. Human radiolabeled mass balance studies: objectives, utilities and limitations. Biopharm Drug Dispos. 2009;30:185–203. https://doi.org/10.1002/bdd.661
Stepan AF, Kalgutkar, AS. Fundamentals of organic chemistry as applicable to the biotransformation of foreign compounds. In: Lee PW, Aizawa H, Gan LL, Prakash C, Zhong D, editors. Handbook of Metabolic Pathways of Xenobiotics. First Edition. New York: Wiley and Sons; 2014. p. 27–59
Chiba K, Trevor A, Castagnoli N Jr. Metabolism of the neurotoxic tertiary amine, MPTP, by brain monoamine oxidase. Biochem Biophys Res Commun. 1984;120:574–8. https://doi.org/10.1016/0006-291x(84)91293-2
Castagnoli N Jr., Chiba K, Trevor AJ. Potential bioactivation pathways for the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Life Sci. 1985;36:225–30. https://doi.org/10.1016/0024-3205(85)90063-3
Chiba K, Peterson LA, Castagnoli KP, Trevor AJ, Castagnoli N Jr. Studies on the molecular mechanism of bioactivation of the selective nigrostriatal toxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. Drug Metab Dispos. 1985;13:342–7
Peterson LA, Caldera PS, Trevor A, Chiba K, Castagnoli N Jr. Studies on the 1-methyl-4-phenyl-2,3-dihydropyridinium species 2,3-MPDP+, the monoamine oxidase catalyzed oxidation product of the nigrostriatal toxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). J Med Chem. 1985;28:1432–6. https://doi.org/10.1021/jm00148a010
Langston JW, Forno LS, Rebert CS, Irwin I. Selective nigral toxicity after systemic administration of 1-methyl-4-phenyl-1,2,5,6-tetrahydropyrine (MPTP) in the squirrel monkey. Brain Res. 1984;292:390–4. https://doi.org/10.1016/0006-8993(84)90777-7
Langston JW, Irwin I, Langston EB, Forno LS. 1-Methyl-4-phenylpyridinium ion (MPP+): identification of a metabolite of MPTP, a toxin selective to the substantia nigra. Neurosci Lett. 1984;48:87–92. https://doi.org/10.1016/0304-3940(84)90293-3
Nicklas WJ, Vyas I, Heikkila RE. Inhibition of NADH-linked oxidation in brain mitochondria by 1-methyl-4-phenyl-pyridine, a metabolite of the neurotoxin, 1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine. Life Sci. 1985;36:2503–8. https://doi.org/10.1016/0024-3205(85)90146-8
Dunigan CD, Shamoo AE. Identification of the major transport pathway for the parkinsonism-inducing neurotoxin 1-methyl-4-phenylpyridinium. Neuroscience. 1996;75:37–41. https://doi.org/10.1016/0306-4522(96)00266-7
Sablin SO, Krueger MJ, Bachurin SO, Solyakov LS, Efange SM, Singer TP. Oxidation products arising from the action of monoamine oxidase B on 1-methyl-4-benzyl-1,2,3,6-tetrahydropyridine, a nonneurotoxic analogue of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. J Neurochem. 1994;62:2012–6. https://doi.org/10.1046/j.1471-4159.1994.62052012.x
Naiman N, Rollema H, Johnson E, Castagnoli N Jr. Studies on 4-benzyl-1-methyl-1,2,3,6-tetrahydropyridine, a nonneurotoxic analogue of the parkinsonian inducing agent 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. Chem Res Toxicol. 1990;3:133–8. https://doi.org/10.1021/tx00014a008
Zhao Z, Dalvie D, Naiman N, Castagnoli K, Castagnoli N Jr. Design, synthesis, and biological evaluation of novel 4-substituted 1-methyl-1,2,3,6-tetrahydropyridine analogs of MPTP. J Med Chem. 1992;35:4473–8. https://doi.org/10.1021/jm00101a026
Kalgutkar AS, Castagnoli K, Hall A, Castagnoli N Jr. Novel 4-(aryloxy)tetrahydropyridine analogs of MPTP as monoamine oxidase A and B substrates. J Med Chem. 1994;37:944–9. https://doi.org/10.1021/jm00033a012
Dalvie Zhao Z D, Castagnoli N Jr. Characterization of an unexpected product from a monoamine oxidase B generated 2,3-dihydropyridinium species. J Org Chem. 1992;57:7321–4
Flaherty P, Castagnoli K, Wang YX, Castagnoli N Jr. Synthesis and selective monoamine oxidase B-inhibiting properties of 1-methyl-1,2,3,6-tetrahydropyrid-4-yl carbamate derivatives: potential prodrugs of (R)- and (S)-nordeprenyl. J Med Chem. 1996;39:4756–61. https://doi.org/10.1021/jm960477e
Kamel A, Colizza K, Obach RS. In vitro metabolism of the 5-hydroxytryptamine1B receptor antagonist elzasonan. Xenobiotica. 2013;43:368–78. https://doi.org/10.3109/00498254.2012.723150
Kamel A, Obach RS, Colizza K, Wang W, O’Connell TN, Coelho RV Jr, et al. Metabolism, pharmacokinetics, and excretion of the 5-hydroxytryptamine1b receptor antagonist elzasonan in humans. Drug Metab Dispos. 2010;38:1984–99. https://doi.org/10.1124/dmd.110.034595
Naisbitt DJ, Williams DP, Pirmohamed M, Kitteringham NR, Park BK. Reactive metabolites and their role in drug reactions. Curr Opin Allergy Clin Immunol. 2001;1:317–25. https://doi.org/10.1097/01.all.0000011033.64625.5a
Baillie TA, Davis MR. Mass spectrometry in the analysis of glutathione conjugates. Biol Mass Spectrom. 1993;22:319–25. https://doi.org/10.1002/bms.1200220602
Johnson BM, van Breemen RB. In vitro formation of quinoid metabolites of the dietary supplement Cimicifuga racemosa (black cohosh). Chem Res Toxicol. 2003;16:838–46. https://doi.org/10.1021/tx020108n
Leung L, Kalgutkar AS, Obach RS. Metabolic activation in drug-induced liver injury. Drug Metab Rev. 2012;44:18–33. https://doi.org/10.3109/03602532.2011.605791
Potter WZ, Davis DC, Mitchell JR, Jollow DJ, Gillette JR, Brodie BB. Acetaminophen-induced hepatic necrosis. 3. Cytochrome P-450-mediated covalent binding in vitro. J Pharm Exp Ther. 1973;187:203–10
Jollow DJ, Mitchell JR, Potter WZ, Davis DC, Gillette JR, Brodie BB. Acetaminophen-induced hepatic necrosis. II. Role of covalent binding in vivo. J Pharm Exp Ther. 1973;187:195–202
Mitchell JR, Jollow DJ, Potter WZ, Davis DC, Gillette JR, Brodie BB. Acetaminophen-induced hepatic necrosis. I. Role of drug metabolism. J Pharm Exp Ther. 1973;187:185–94
Wang A, Zhao Q, Liu M, Wang Y, Zhao G, Li W, et al. In Vitro and In Vivo Metabolic Activation of Tolterodine Mediated by CYP3A. Chem Res Toxicol. 2023;36:479–91. https://doi.org/10.1021/acs.chemrestox.2c00389
Dahlin DC, Miwa GT, Lu AY, Nelson SD. N-acetyl-p-benzoquinone imine: a cytochrome P-450-mediated oxidation product of acetaminophen. Proc Natl Acad Sci USA. 1984;81:1327–31. https://doi.org/10.1073/pnas.81.5.1327
Chen W, Koenigs LL, Thompson SJ, Peter RM, Rettie AE, Trager WF, et al. Oxidation of acetaminophen to its toxic quinone imine and nontoxic catechol metabolites by baculovirus-expressed and purified human cytochromes P450 2E1 and 2A6. Chem Res Toxicol. 1998;11:295–301. https://doi.org/10.1021/tx9701687
Kalgutkar AS. Liabilities Associated with the Formation of “Hard” Electrophiles in Reactive Metabolite Trapping Screens. Chem Res Toxicol. 2017;30:220–38. https://doi.org/10.1021/acs.chemrestox.6b00332
Gorrod JW, Aislaitner G. The metabolism of alicyclic amines to reactive iminium ion intermediates. Eur J Drug Metab Pharmacokinet. 1994;19:209–17. https://doi.org/10.1007/BF03188923
Argoti D, Liang L, Conteh A, Chen L, Bershas D, Yu CP, et al. Cyanide trapping of iminium ion reactive intermediates followed by detection and structure identification using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Chem Res Toxicol. 2005;18:1537–44. https://doi.org/10.1021/tx0501637
Murphy PJ. Enzymatic oxidation of nicotine to nicotine 1’(5’) iminium ion. A newly discovered intermediate in the metabolism of nicotine. J Biol Chem. 1973;248:2796–800
Ho B, Castagnoli N Jr. Trapping of metabolically generated electrophilic species with cyanide ion: metabolism of 1-benzylpyrrolidine. J Med Chem. 1980;23:133–9. https://doi.org/10.1021/jm00176a006
Ward DP, Trevor AJ, Kalir A, Adams JD, Baillie TA, Castagnoli N Jr. Metabolism of phencyclidine. The role of iminium ion formation in covalent binding to rabbit microsomal protein. Drug Metab Dispos. 1982;10:690–5
Kalgutkar AS, Dalvie DK, Aubrecht J, Smith EB, Coffing SL, Cheung JR, et al. Genotoxicity of 2-(3-chlorobenzyloxy)-6-(piperazinyl)pyrazine, a novel 5-hydroxytryptamine2c receptor agonist for the treatment of obesity: role of metabolic activation. Drug Metab Dispos. 2007;35:848–58. https://doi.org/10.1124/dmd.106.013649
Kalgutkar AS, Bauman JN, McClure KF, Aubrecht J, Cortina SR, Paralkar J. Biochemical basis for differences in metabolism-dependent genotoxicity by two diazinylpiperazine-based 5-HT2C receptor agonists. Bioorg Med Chem Lett. 2009;19:1559–63. https://doi.org/10.1016/j.bmcl.2009.02.032
Author information
Authors and Affiliations
Corresponding authors
Ethics declarations
Conflict of interest
Dr DD and Dr AK are employees of Crinetics Pharmaceuticals and Pfizer, respectively.
Additional information
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Dalvie, D., Kalgutkar, A.S. Utilizing mechanistic organic chemistry training to study drug metabolism in preclinical drug discovery/development. Med Chem Res 32, 1922–1932 (2023). https://doi.org/10.1007/s00044-023-03085-z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00044-023-03085-z