Preparation and Utilization of Chiral alpha-and beta-Hydroxyacetylenes

为了获得多功能的手性2-环戊烯醇结构单元，研究了几种2-取代的2-环戊烯醇衍生物的酶促拆分。经过测试，2-乙氧羰基-2-环戊烯醇已干净地拆分脂肪酶PS在两个转酯在有机溶剂中和脱酰在缓冲溶液中，在几乎完全的对映体特异性的方式在高的化学产率。由于酶促反应的特点，反应发生在同一立体构型上，使对映体互补拆分成为可能，利用所得光学纯的环戊烯醇，实现了关键中间体1，25-二羟基维生素D_3和长春胺的高效合成。

Intending to obtain versatile chiral 2-cyclopentenol building blocks, enzymatic resolution of several 2-substituted 2-cyclopentenol derivatives has been investigated. Having been tested, 2-carbethoxy-2-cyclopentenol has been cleanly resolved by lipase PS under both trans-esterification in organic solvent and deacylation in buffer solution in virtually complete enantiospecific manner in high chemical yields. Owing to characteristic feature of the enzymatic reaction, the reaction occurred at the same stereogenic configuraion which made enantiocomplementary resolution possible.Utilizing the optically pure cyclopentenols thus obtained, efficient syntheses of the key intermediate of 1,25-dihydroxyvitamin D_3 and vincamine have been achieved.