title: Hydroxylamine inactivation of cephalosporins: nucleophilic attack on beta-lactam structures.
abstract: Cephalosporins are not degraded by hydroxylamine (NH2OH) in neutral and acidic solutions. Their reaction with NH2OH in slightly alkaline solutions leads to microbiological inactivation which seems to be a structure dependent phenomenon. In these experiments the mandelic acid-type compounds appear to be quite stable to the effect of NH2OH, whereas, cefazolin is gradually degraded and the straight chain-containing cephalosporins are variably inactivated. The phenylglycine-type oral cephalosporins were generally sensitive to the alkaline conditions used in these tests and apparently are not inactivated by NH2OH. On the contrary, the phenylglycine-type cephalosporins seem to be somewhat stabilized in the presence of NH2OH.
mesh_terms: D000667:Ampicillin / Q000037:antagonists & inhibitors; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001412:Bacillus subtilis / Q000187:drug effects / Q000378:metabolism; D002506:Cephalexin / Q000037:antagonists & inhibitors; D002507:Cephaloglycin / Q000037:antagonists & inhibitors; D002511:Cephalosporins / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D055598:Chemical Phenomena; D002621:Chemistry; D006863:Hydrogen-Ion Concentration; D019811:Hydroxylamine; D006898:Hydroxylamines / Q000494:pharmacology*; D010400:Penicillin G / Q000037:antagonists & inhibitors
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D006898:Hydroxylamines; D019811:Hydroxylamine; D000667:Ampicillin; D002507:Cephaloglycin; D002506:Cephalexin; D010400:Penicillin G