Novel 3-acyloxymethyl-cephem compounds of the formula: ##STR1## wherein R.sup.1 is hydrogen or an acyl group; X is a divalent group consisting of a carbon chain having 2 to 3 carbon atoms and a carbonyl or sulfonyl group at one terminal end thereof, said divalent group being either substituted or unsubstituted on the carbon chain; and Z is an organic acid residue, and salts thereof were found to be useful as starting materials for preparing cephalosporins of the formula: ##STR2## wherein R.sup.2 stands for a residue of a nucleophilic compound and R.sup.1 has the same meaning as above.
化合物的名称为Novel 3-acyloxymethyl-cephem,分子式为: ##STR1## 其中R1为氢或酰基;X为二价基团,由具有2到3个碳原子的碳链和一个在其末端具有羰基或磺酰基的基团组成,该二价基团在碳链上可以是取代或未取代的;Z为有机酸残基,其盐也可用作制备下式中
头孢菌素的起始材料: ##STR2## 其中R2代表亲核化合物的残基,R1具有与上述相同的含义。