An expedient enantioselective synthetic approach for the gypsy moth sex-attractant pheromone cis-(+)-1 and trans-(+)-disparlure 2 is described employing the optimized combination of organocatalytic MacMillan’s self aldol reaction, Wittig olefination, regioselective ring opening of an epoxide and Mitsunobu esterification reactions as key steps.
We report a series of shortpeptides possessing the sequence (FE)n or (EF)n and bearing l‐proline at their N‐terminus that self‐assemble into high aspect ratio aggregates and hydrogels. We show that these aggregates are able to catalyze the aldol reaction, whereas non‐aggregated analogues are catalytically inactive. We have undertaken an analysis of the results, considering the accessibility of catalytic
我们报道了一系列短肽,它们的序列在其N端带有(FE)n或(EF)n序列,并带有l-脯氨酸,它们可以自组装成高长宽比的聚集体和水凝胶。我们表明,这些聚集体能够催化羟醛反应,而非聚集的类似物具有催化活性。考虑到催化部位的可及性,我们对结果进行了分析,p K a价值转移,以及疏水口袋的存在。我们得出结论,疏水区的存在确实与底物溶解有关,但是活性位点可及性是观察到的反应速率差异的关键因素。此处提供的结果提供了一个由自组装引起的新化学性质出现的示例,并支持了自组装肽在益生元场景中发挥的相关作用。从这个意义上说,所报道的系统可以看作是原始的醛缩酶I模拟物,并且已经成功地测试了简单碳水化合物前体的合成。
Total Synthesis and Structural Revision of Callipeltoside C
作者:Joseph Carpenter、Alan B. Northrup、deMichael Chung、John J. M. Wiener、Sung-Gon Kim、David W. C. MacMillan
DOI:10.1002/anie.200800086
日期:2008.4.28
The Importance of Iminium Geometry Control in Enamine Catalysis: Identification of a New Catalyst Architecture for Aldehyde-Aldehyde Couplings
作者:Ian K. Mangion、Alan B. Northrup、David W. C. MacMillan
DOI:10.1002/anie.200461851
日期:2004.12.10
Enantioselective Organocatalytic Direct Aldol Reactions ofα-Oxyaldehydes: Step One in a Two-Step Synthesis of Carbohydrates
作者:Alan B. Northrup、Ian K. Mangion、Frank Hettche、David W. C. MacMillan