| 摘要 |
PROBLEM TO BE SOLVED: To obtain, in high purity and yield under mild conditions, a compound useful as a side chain intermediate for cephem-based antibiotics by acylating a 2-(2-aminothiazol-4-yl)-2-hydroxyiminoacetate with an actid anhydride in the presence of a base. SOLUTION: The objective compound of formula III is obtained by reaction of (A) a compound of formula I [R<1> is a (substituted) 1-8C alkyl, (substituted) 3-8C alkenyl, (substituted) 7-20C aralkyl, benzoylalkyl or (substituted) aryl] with (B) a compound of formula II [R<2> and R<3> are each a (substituted) 1-6C alkyl, (substituted) 7-15C aralkyl or (substituted) aryl] in the presence of (C) a basic catalyst such as potassium (bi)carbonate or sodium (bi)carbonate. |
