Derivatives of 7-oxo-4-oxa-diazabicyclo-(3.2.0)-hept-2-en not substituted in position 6, processes for their preparation and their use as intermediates in the synthesis of beta-lactam antibiotics

摘要

A compound of the formula IMAGE in which R is hydrogen, or optionally substituted alkyl, alkenyl, alkinyl, aralkyl, aryl, heteroaryl, heteroaralkyl, aryloxyalkyl, heteroaryloxyalkyl, alkoxyalkyl, arylthioalkyl, heteroarylthioalkyl, alkylthioalkyl, alkoxy, aryloxy, alkylthio or arylthio. The compounds are prepared by novel processes and are suitable as intermediates for beta -lactam antibiotics.