开发了铜催化的2-芳基氮丙啶和环状甲硅烷基二烯醇醚的非对映选择性[3 + 2]环加成反应,以有效构建稠合-[5, n ]碳环吡咯烷,该化合物广泛存在于生物活性天然产物中。机理研究表明,这种转化的高非对映选择性源于连续的逆向氮杂迈克尔/差向异构化/氮杂迈克尔过程。利用这种新开发的方法,首次实现了 pancratinines B 和 C 的全合成。
Enzymatic kinetic resolution of racemic cyanohydrins via enantioselective acylation
作者:Qing Xu、Yongli Xie、Xiaohong Geng、Peiran Chen
DOI:10.1016/j.tet.2009.11.074
日期:2010.1
Enzymatickineticresolution of a series of aromatic and aliphatic cyanohydrins in organic media has been investigated. The behavior of potential lipases, molecular sieves, acyl reagent, reaction temperature, and organic solvents on the kineticresolution was studied. The influence of substrate structure, steric, and electronic nature and position of the aryl substituent on the enantioselectivity was
Process for producing optically active alpha-hydrocarboxylic acid having phenyl group
申请人:NITTO CHEMICAL INDUSTRY CO., LTD.
公开号:EP0610048A2
公开(公告)日:1994-08-10
A biological process for predominantly producing an optically active α-hydroxycarboxylic acid having a phenyl group directly from a racemic α-hydroxynitrile or a mixture of an aldehyde corresponding to the nitrile and prussic acid as a substrate is disclosed, comprising reacting a microorganism belonging to the genus Gordona with the substrate in a neutral to basic aqueous medium. A desired optically active α-hydroxycarboxylic acid having a phenyl group can be obtained quantitatively at a high optical purity.
Method of producing optically active alpha-hydroxy acid or alpha-hydroxyamide
申请人:NITTO CHEMICAL INDUSTRY CO., LTD.
公开号:EP0711836A1
公开(公告)日:1996-05-15
A reaction system, wherein a cyanohydrin is converted into an optically active α-hydroxy acid or α-hydroxyamide via a treatment in a reaction tank (f) with a microorganism, is provided with an automatic cyanohydrin controller (h) comprising a cyano ion detector (a), a regulator (b) and a cyanohydrin supplier (i) and (j) linked thereto. The reaction is performed while automatically controlling the cyanohydrin concentration.
Thus cyanohydrin can be supplied under automatic control at a relatively low and constant concentration on the basis of its consumption ratio. The reaction rate of the catalyst can be continuously regarded as the rate-limiting factor. As a result, a decrease in the enzymatic activity during the reaction can be suppressed and an optically active α-hydroxy acid or α-hydroxyamide can be efficiently obtained at a high yield.
Kinetic resolution of cyanohydrins via enantioselective acylation catalyzed by lipase PS-30
作者:Qing Xu、Xiaohong Geng、Peiran Chen
DOI:10.1016/j.tetlet.2008.08.090
日期:2008.11
By using lipase PS-30 as catalyst, the kinetic resolution of a series of racemic cyanohydrins has been achieved via enantioselective acylation. The values of kinetic enantiomeric ratio (E) reached up to 314. Substituent effect is also briefly discussed. (C) 2008 Elsevier Ltd. All rights reserved.