Synthesis, in Silico and in Vitro Study on Phase I Metabolism of the Potent 5-Ht7/5-Ht1a/D2 Receptor Ligand: 4-Fluoron -(1-{2-[2-(Methylsulfanyl)- Phenoxy]Ethyl}Pyrrolidin-3-Yl) Benzene Sulfonamide

Abstract

In the present study we analyze the synthesis as well as biotransformation pathways and metabolic stability of 4-fluoro- N -(1-{2-[2-(methylsulfanyl)phenoxy]ethyl}pyrrolidin-3-yl) benzene sulfonamide – thioether compound 5, with the affinity for several subtypes of the serotonin and dopamine receptor. Studies were conducted in vitro on liver microsomes from three species – mouse, rat, and human. The biotransformation was analyzed using liquid chromatography coupled with mass spectrometry. Two major metabolites (M1 and M2) – products of S-oxidation of the parent molecule – were generated both by in silico and in vitro methods. Use of three species allowed us to determine the interspecies differences in metabolic stability of tested compound. Two parameters, t_0.5 and Cl_int , were calculated. Compound 5 was the most stable in human liver microsomes. Results are useful for understanding the interspecies differences in metabolism of the serotonin and dopamine receptor ligand associated with sulfur atom.