Fragmentation procedure for preparing 3-amino-azetidinones

摘要

When 3-(2-hydroxyiminoacetylamino)-2-oxo-azetidine compounds are treated with reactive derivatives of carbonic acid half-esters in aqueous media in the presence of bases a fragmentation takes place which, in addition to 3-amino-2-oxo-azetidines, also yields nitriles which, compared with the 2-hydroxyiminoacetyl group, have one less carbon atom. The resulting products are intermediates for the preparation of nocardicin-like antibiotics. The deacylation procedure of this specification offers advantages over the multi-stage deacylation procedure known hitherto, inasmuch as higher yields of 3-amino-2-oxoazetidine compounds are obtained and the acyl group can be obtained in the form of a nitrile which is shorter by one carbon atom.