环氧化物水解酶 (EH) 存在于所有生物体中,可催化环氧化物水解为相应的邻二醇。EH参与内源性和外源性环氧化物的代谢,因此在药理学和生物技术方面有应用。在这项工作中,我们描述了最近从丝状真菌里氏木霉 QM9414 (TrEH) 克隆的环氧化物水解酶的底物和抑制剂选择性。我们还研究了基于 TrEH 尿素的抑制剂对真菌生长的影响。TrEH 对放射性和荧光替代物和天然底物,尤其是来自二十二碳六烯酸的环氧化物显示出高活性。使用荧光替代底物,鉴定了 TrEH 的有效抑制剂。有趣的是,最好的化合物之一抑制了里氏木霉生长的 60%,表明 TrEH 具有内源性作用。
Reagent-Controlled Asymmetric Homologation of Boronic Esters by Enantioenriched Main-Group Chiral Carbenoids
作者:Paul R. Blakemore、Stephen P. Marsden、Huw D. Vater
DOI:10.1021/ol053055k
日期:2006.2.1
and (S)-1-chloro-2-phenylethyllithium (26), generated in situ by sulfoxide ligand exchange from (-)-(R(S),R)-1-chloro-2-phenylethyl p-tolyl sulfoxide (8), effected the stereocontrolled homologation of boronicesters. sec-Alcohols derived from the product boronates by oxidation with basic hydrogen peroxide exhibited % ee closely approaching that of sulfoxide 8 in examples employing Li-carbenoid 26.
alpha-Chloro- and alpha-bromoalkyl Grignard reagents 11 and 30 with > 97% ee (enantiomeric excess) were generated by a sulfoxide/magnesium exchange reaction from the enantiomerically and diastereomerically pure sulfoxides 25 and 27. The resulting alpha-haloalkyl Grignard reagents are configurationally stable at -78 degrees C. Racemization sets in at or above -60 degrees C, especially when the solution
Simple Diastereoselectivity on Addition of α-Haloalkyl Grignard Reagents to Benzaldehyde
作者:Volker Schulze、Peter G. Nell、Andrew Burton、Reinhard W. Hoffmann
DOI:10.1021/jo034138m
日期:2003.5.1
The addition of alpha-haloalkyl Grignard reagents to benzaldehyde occurs with simple diastereoselectivity substantially higher than that of the corresponding lithium reagents. Reaction in the presence of dimethyl-aluminum chloride suppresses subsequent Oppenauer oxidation of the resulting Mg-alkoxides by excess benzaldehyde.
An enantioselective iodine/magnesium exchange reaction between the diiodoalkane 4 and a chiral Grignard reagent 12 has been realized at - 78 degrees C in THE The resulting alpha-iodoalkylmagnesium reagents 13 are configurationally stable under these conditions and during trapping by a benzaldehyde/dimethylaluminium chloride system to furnish the iodohydrins 19 and epoxides 9.