| 摘要 |
<p>Medicinally active penicillanic acid or cephalosporanic acid derivatives and salts, and intermediates therefor, of the formula (I) wherein R1 stands for hydrogen or an easily removable ester-forming or salt group, preferably a trialkylamine, trialkylsilyl, trichloroethyl, acetoxymethyl, phenacyl, substituted phenacyl, substituted phenyl or benzyl group, R2 stands for hydrogen, alkyl group, alkenyl group, alkyl group having an aryl or heterocyclic (preferably furyl or thienyl) substituent, an aryl group having an alkyl substituent (preferably xylyl), or an aryl, aralkyl or heterocyclic group (preferably a phenyl, thienyl or furyl group) having optionally one or more substituent(s), R3 stands for hydrogen, or an optionally substituted aryl, alkyl, cycloalkyl or aralkyl group, and X stands for .mu. group of the formul? are prepared by acylating an amine of the formula wherein X has the same meanings as defined above and R4 is an easily removable ester-forming group, preferably a trialkylamino, trialkyisilyl, trichloroethyl, acetoxymethyl, phenacyl, substituted phenacyl, substituted phenyl or benzyl group, or a salt formed preferably with an alkyli metal or a trialkylamine, with an ester of the formula wherein R2 has the same meanings as defined above and R5 stands for an optionally substituted aryl, alkyl, cycloalkyl or aralkyl group, and where required splitting off substituents R4 and/or R5. Those compounds of formula(I) in which R2 is alkyl are novel compounds which also form an embodiment of the invention.</p> |
