Total synthesis of nuclear analogues of 7-methylcephalosporin

Abstract

A synthetic route which was developed for the preparation of nuclear analogues of the penicillins and cephalosporins has been used to synthesise 8-oxo-7α-phenylacetamido-6αH-1-aza-4-thiabicyclo[4.2.0]octane-2α-carboxylic acid (19),7α-methyl-8-oxo-7β-phenylacetamido-6αH-1-aza-4-thiabicyclo[4.2.0]octane-2α-carboxylic acid (27), and 7α-methyl-8-oxo-7β-phenylacetamido-6αH-1-aza-4-thiabicyclo[4.2.0]oct-2-ene-2-carboxylic acid (30).