title: Preparation and structure-activity relationships of some 6 alpha-substituted penicillins.
abstract: The influence on the antibacterial activity of introducing a 6 alpha-methoxy group into carbenicillin, and various 6 alpha-substituents into sulbenicillin and piperacillin was examined. Further variations of the side chain aryl group were examined in the 6 alpha-methoxy substituted series. This led to the identification of disodium 6 beta-(D,L-2-carboxy-2-thien-3-ylacetamido)-6 alpha-methoxypenicillanate (5b) as a beta-lactamase stable derivative with useful activity against Enterobacteriaceae, and disodium 6 beta-[D-2-(4-aminophenyl)-2-sulfoacetamido]-6 alpha-methoxypenicillanate (6e) with slightly lower activity against the Enterobacteriaceae but more active against Pseudomonas aeruginosa.
mesh_terms: D004755:Enterobacteriaceae / Q000187:drug effects; D010406:Penicillins / Q000138:chemical synthesis* / Q000494:pharmacology; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D013329:Structure-Activity Relationship
chemical_list: D010406:Penicillins