A process for preparing azetidinones of the formula: ##STR1## wherein R.sup.1 is an amino-protecting group and R.sup.2 is alkyl or aryl, which comprises reacting compounds of the formulae (VIII) and (IX) ##STR2## wherein L is a leaving group. The product azetidinones are intermediates in the preparation of penem and carbapenem antibiotics.
一种制备式为##STR1##的杂环酮的方法,其中R.sup.1是
氨基保护基,R.sup.2是烷基或芳基,包括反应式为(VIII)和(IX)的化合物##STR2##其中L为离去基团。所得的杂环酮是制备青霉烷和碳青霉烯类抗生素的中间体。