DESULPHURATIVE APPROACHES TO PENEM ANTIBIOTICS. II. 4-ACYLDITHIOAZETIDIN-2-ONES FROM PENICILLIN DERIVED SULPHENIMIDES, THIOLSULPHONATES AND DISULPHIDES.

Article abstract of DOI:10.1016/S0040-4039(00)81728-1

Displacement of different leaving groups from a number of 2-oxo-azetidin-4-ylthio derivatives with thioacids, followed by sulphur extrusion, provides a facile access to β-lactam thioesters and hence to penems.