title: Synthesis and biological activity of 5-(4-chlorobenzoyl)-4-(hydroxymethyl)-1-methyl-1H-pyrrole-2-acetic acid, a major metabolite of zomepirac sodium.
abstract: 5-(4-Chlorobenzoyl)-4-(hydroxymethyl)-1-methyl-1H-pyrrole-2-acetic acid (2), the major oxidative metabolite of zomepirac (1), was synthesized starting with ethyl 5-(4-chlorobenzoyl)-1,4-dimethyl-1H-pyrrole-2-acetate (3), the ethyl ester of 1. Compound 3 was oxidized with selenium dioxide to afford the alpha-oxoester, 5. Bromination of 5 with N-bromosuccinimide produced bromomethylpyrrole 7, and reaction of 7 with acetate produced by corresponding acetoxymethylpyrrole 8. Hydrogen sulfide effected the selective reduction of the side-chain carbonyl group if 8 to give 9. Saponification of 9 gave the title compound, 2. Synthetic 2 was identical with the isolated metabolite of zomepirac (1). Biological testing revealed that the metabolite was essentially devoid of the biological activity associated with zomepirac.
mesh_terms: D000700:Analgesics / Q000138:chemical synthesis / Q000378:metabolism* / Q000494:pharmacology; D000818:Animals; D001169:Arthritis, Experimental / Q000188:drug therapy; D006801:Humans; D066298:In Vitro Techniques; D010974:Platelet Aggregation / Q000187:drug effects; D011758:Pyrroles / Q000031:analogs & derivatives; D051381:Rats; D013276:Stomach Ulcer / Q000139:chemically induced; D014046:Tolmetin / Q000031:analogs & derivatives
chemical_list: D000700:Analgesics; D011758:Pyrroles; C020549:zomepirac; D014046:Tolmetin