title: 3-Cyanocephems, and carbon-3 heterocyclic-substituted cephems via 1,3-dipolar cycloadditions.
abstract: The transformation is described of 3-formylcephem 1 into its oxime, substituted oximes, and substituted hydrazones and, thence, into the 3-cyano, 3-diazomethyl, and 3-oxonitrilomethyl derivatives. These reactive 1,3-dipoles undergo 1,3-dipolar cycloadditions with various dipolarophiles to give C-3 heterocyclic-substituted cephems.
mesh_terms: D002511:Cephalosporins / Q000138:chemical synthesis* / Q000494:pharmacology; D003500:Cyclization; D008826:Microbial Sensitivity Tests; D013211:Staphylococcus aureus / Q000187:drug effects; D013297:Streptococcus pyogenes / Q000187:drug effects
chemical_list: D002511:Cephalosporins