title: Structure--activity relationships in cephalosporins prepared from penicillins. 2. Analogues of cephalexin substituted in the 3-methyl group.
abstract: A previously outlined general procedure for preparing various 3-substituted cephalosporins from the penicillin nucleus has been used, with modifications where required, to prepare a series of analogues of cephalexin with various substituents in the 3-methyl group. The 3-substituents most conducive to broad-spectrum antibacterial activity were 3-pyridylmethyl and m- or p-carboxybenzyl. The compounds were only poorly absorbed by the oral route in mice, but the 3-(carboxybenzyl) compounds gave more prolonged useful serum levels than the usual cephalosporins.
mesh_terms: D000818:Animals; D001419:Bacteria / Q000187:drug effects; D002506:Cephalexin / Q000031:analogs & derivatives* / Q000097:blood / Q000138:chemical synthesis / Q000494:pharmacology; D051379:Mice; D008826:Microbial Sensitivity Tests; D013211:Staphylococcus aureus / Q000187:drug effects; D013329:Structure-Activity Relationship; D013997:Time Factors
chemical_list: D002506:Cephalexin