Preparation, Structure, and Properties of All Possible Cyclic Dimers (Diolides) of 3-Hydroxybutanoic Acid
作者:Dieter Seebach、Torsten Hoffmann、Florian N. M. Kühnle、Joachim N. Kinkel、Michael Schulte
DOI:10.1002/hlca.19950780611
日期:1995.9.20
Accordingly, these compounds show reactivities similar to those of carboxylic-acid anhydrides or even acid chlorides. They cannot be chromatographed on silica gel, and they react with primary, secondary, and tertiary alcohols, and with amines to form derivatives of open chain 3-HB ‘dimers’, hydroxy acids 6, esters 7, and amides 8 (Scheme 2). The rate of acid-catalyzed ring opening of the diolides 1 with
与所提出的结构连接的反式聚之间由一个复杂的-membrane细胞离子通道[([R多磷酸钙)-3-羟基丁酸](P(3-HB))和,CAPP我(约150个单位每),它应该包含s-顺式键甚至更高的酯构象,我们已经制备并研究了3-HB环二聚体(乙交酯1)的性质。的所有可能的形式1中,外消旋-时,内消旋-和对映体纯(- [R ,- [R )-和(小号,小号制备,纯化和表征化合物。合成(方案1)从琥珀酸二甲酯开始,关键步骤是外消旋-和内消旋-2,5-二甲基环己烷-1,4-二酮5的Baeyer-Villiger氧化。所述外消旋-diolide 1物用制备型色谱法解决CHIRALCEL OD柱(图1)。通过X射线衍射确定rac - 1(图3)和meso - 1(图5)的晶体结构:二醇化物1含有顺式-酯键和酯基,其构象位于旋转过渡态的一半(图2)。对于二元醇化物1,建议的应变能高达17.8kcal / mo