反应详情

According to the Hungarian Patent Specification No. 163,143 racemic, cis compounds of the formula (I) and optically active, cis compound of the formula (Ic) were prepared by hydrolyzing the pharmaceutically active vincamine and converting the vincaminic acid obtained into a desired ester from which the corresponding apovincaminic acid ester was obtained by splitting off water; or alternatively, vincamine was first converted into apovincamine by splitting off water which was then subjected to hydrolysis and the apovincaminic acid obtained was converted into a desired ester. This process is disadvantageous in that at first vincamine should be prepared by a multi-step synthesis from which the corresponding apovincaminic acid esters can be prepared with a yield of at most 60% only.

1. customwas then subjected to hydrolysis