Sex pheromone of pine sawflies: Enantioselective lipase catalysed transesterification of erythro-3,7-dimethylpentadecan-2-ol, diprionol
作者:Mårten Lundh、Olof Smitt、Erik Hedenström
DOI:10.1016/0957-4166(96)00428-4
日期:1996.11
(2S,3S,7R/S)-3,7-Dimethylpentadecan-2-ol (2S,3S,7R/S)-1 was prepared with less then 0.5% of (2R,3R,7R/S)-3,7-dimethylpentadecan-2-ol via Pseudomonas sp. (PSL) catalysed transesterification of a 1:1:1:1 mixture of the four erythro-3,7-dimethylpentadecan-2-ols and vinyl acetate in n-heptane at initial low water activity (a(W) < 0.1). (2S,3S,7S)-3,7-Dimethylpentadecan-2-ol (Diprionol) is the precursor to the behaviourally active diprionyl acetate used by the female pine sawfly Neodiprion sertifer as a sexual pheromone. Several lipases, solvents and reaction conditions were tested, and the best results (enantiomeric ratio E = 110) were obtained with Pseudomonas sp. (PSL) and vinyl acetate in iso-octane at initial water activity a(W) < 0.32, When using Candida rugosa (CRL, immobilised on polypropylene) as the catalyst in an esterification reaction with rac-4-methyl-dodecanoic acid and eicosanol at a(W) = 0.8 in cyclohexane a pronounced enantioselectivity was obtained (E = 19). Copyright (C) 1996 Elsevier Science Ltd
(2S,3S,7R/S)-3,7-二甲基十五烷-2-醇(2S,3S,7R/S)-1通过对产碱杆菌(PSL)催化的酯交换反应制得,其中(2R,3R,7R/S)-3,7-二甲基十五烷-2-醇的含量低于0.5%。该反应使用1:1:1:1比例混合的四种赤式-3,7-二甲基十五烷-2-醇与醋酸乙烯酯为原料,在n-庚烷中进行,初始含水量较低(a_W < 0.1)。
(2S,3S,7S)-3,7-二甲基十五烷-2-醇(Diprionol)是行为活性的二吡仑基乙酸的前体,后者被雌性松树锯蝇Neodiprion sertifer用作性信息素。
研究人员测试了多种脂肪酶、溶剂和反应条件,并发现最佳结果(对映体比例E = 110)是在初始含水量a_W < 0.32的异辛烷中,使用产碱杆菌(PSL)和醋酸乙烯酯作为催化剂时获得。
在使用Candida rugosa(CRL,固定化在聚丙烯上)作为催化剂,在a_W = 0.8的环己烷中进行酯化反应,将外消旋的4-甲基十二酸与二十醇反应时,获得了显著的对映选择性(E = 19)。
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