This invention provides a method for conveniently obtaining a compound of formula (Ia) which is a production intermediate of antimicrobial compounds, in which a salt of optically active acid of formula (IIIa) is obtained by allowing a compound of formula (I), a ketone compound and an optically active acid to react with one another, converted into its free form and then hydrolyzed.
In the formula, R1: hydrogen atom or alkyl, aryl or aralkyl group; R2: hydrogen atom or alkyl, aryl, aralkyl, acyl, alkyloxycarbonyl, aralkyloxycarbonyl or substituted sulfonyl; these may further have substituents.)
本发明提供了一种方便地获得化合物公式(Ia)的方法,该化合物是抗微
生物化合物的生产中间体。其中,通过让化合物公式(I)、
酮类化合物和手性酸的盐公式(IIIa)相互反应,转化为其自由形式,然后
水解,从而获得一种手性酸的盐。在公式中,R1:氢原子或烷基、芳基或芳基烷基;R2:氢原子或烷基、芳基、芳基烷基、酰基、烷氧羰基、芳基烷氧羰基或取代磺酰基;这些可能进一步具有取代基。