Direct conversion of N-alkoxy .beta.-lactams to carbapenams: application to the synthesis of the bicyclic PS-5 keto ester
摘要:
The synthesis and direct conversion of N-alkoxy beta-lactams to the carbapenam ring system is described. This novel cyclization apparently proceeds by initial carbene-mediated ylide formation with concomitant rearrangement. The title reaction is applied to the construction of the methyl ester of the bicyclic beta-lactam precursor of PS-5.
Carbapenem compounds of formulae
wherein R₁ is a lower alkyl, R₂ is hydrogen or a substituent other than amino are useful for the treatment of infections.