Transformations of penicillins: reactions of secopenicillanic acid derivatives with ethyl N-chloro-N-sodiocarbamate
Abstract
3β-Acetamido-4-(methylthio)azetidin-2-one (1) did not react with ethyl N-chloro-N-sodiocarbamate, in contrast with its ready reaction with N-chloro-N-sodiotoluene-p-sulphonamide. The 4-(methylsulphinyl)azetidin-2-ones (2) reacted with the former reagent to give 3,3-bis(ethoxyformamido)-4-(methylsulphinyl)azetidin-2-ones (5), whereas the 4-(methylsulphinimidoyl)azetidin-2-ones (3), gave 3,3-bis(ethoxyformamido)-products (8) together with 3β-acetamido-3α-ethoxyformamido-products (9). The sulphimides (8) and (9) were transformed into new 1-ethoxyformamido-4-oxa-2,6-diazabicyclo[3.2.0]hept-2-en-7-ones (11) and (13).