title: Synthesis and angiotensin-converting enzyme inhibitory activity of 3-(Mercaptomethyl)-2-oxo-1-pyrrolidineacetic acids and 3-(Mercaptomethyl)-2-oxo-1-piperidineacetic acids.
abstract: A number of gamma- and delta-lactam derivatives were synthesized and their in vitro angiotensin-converting enzyme (ACE) inhibitory activities were compared. The structures of these compounds were designed to include many of the important features of captopril. The synthesis involved the preparation of a variety of novel 3-methylene-2-pyrrolidinones (3-5 and 16) and 3-methylene-2-piperidinones (3a-5a, 10-12, and 17). The key intermediate 3-methylenelactams 3 and 3a were obtained from 3-(hydroxymethyl)lactams 2 and 2a by a direct dehydration with dicyclohexylcarbodiimide using cuprous iodide as a catalyst. Introduction of the sulfhydryl group was accomplished by a Michael addition of these alpha, beta-unsaturated lactams. The compound with the highest in vitro activity was 3-(mercaptomethyl)-2-oxo-1-piperidineacetic acid (7a). The activity of the 7a both in vitro and in vivo (dog) was shown to be less than that of captopril by a factor of about 100.
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors; D000818:Animals; D002216:Captopril / Q000494:pharmacology; D055598:Chemical Phenomena; D002621:Chemistry; D004285:Dogs; D006168:Guinea Pigs; D006439:Hemodynamics / Q000187:drug effects; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects; D011760:Pyrrolidinones / Q000138:chemical synthesis*; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives / Q000138:chemical synthesis* / Q000494:pharmacology
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D011760:Pyrrolidinones; D002216:Captopril; D011761:Pyrrolidonecarboxylic Acid