Nuclear analogs of β-lactam antibiotics. XII. 2-Oxodesthiocephalosporins

Abstract
Epoxidation of Δ2-1-carbacephems 2 followed by base treatment gave the allylic alcohols 4. Oxidation of 4 gave the 2-keto-Δ3-carbacephem 9 which could be reduced to the isomeric allylic alcohol 7. Conversion of these intermediates to a series of biologically active cephalosporin analogs 13g–l and 14 is described.