Development of CD Method and Application to Stereochemistry

1.视紫红质中视网膜发色团的绝对构象是理解视觉传导过程的核心问题。Nakanishi等人用11个顺式锁定的3/7元环手性视网膜类似物研究了视紫红质中发色团12-13单键的绝对扭曲。哥伦比亚大学。然而，1的绝对构型与CD计算得到的结果不一致。为了明确地确定1的绝对立体化学，我们将“手性邻苯二甲酸法”应用于3/7元醇。双环[5.1.0]辛烷-2，6-二醇(syn-2)与手性二氯邻苯二甲酸(-)-3缩合生成酯(4)的非对映异构体混合物。由酯4B制备的对溴苯甲酸酯(+)-(5)结晶为单晶，适合于X射线衍射。(+)-(5)的(1S，2R，7R)构型由X-r…明确确定More Ay Bijvoet方法2.作为最近开发的生物活性化合物和手性活性有机材料的基本信息，我们正在构建手性数据库“手性世界”。为了收集大量的光盘数据，我们邀请了凯泽斯劳滕大学的库博尔教授，也派了原田教授去那里，我们开发了光盘数据库格式来标准化这些数据。在与伊利诺伊大学Pirkle教授的合作下，用手性邻苯二甲酸法拆分了各种邻位取代二芳基甲醇：(1)外消旋醇与手性邻苯二甲酸的酯化；(2)在硅胶上分离高效液相色谱形成的非对映混合物；(3)从分离的酯中回收对映体醇。以樟脑磺胺为绝对构型的内标，用X-射线单晶衍射法明确测定了邻取代二芳基甲醇手性邻苯二甲酸酯的绝对构型。较少

1. The absolute conformation of the retinal chromophore in rhodopsin is a central problem for understanding the visual transduction process. The absolute twist around the 12-13 single bond of the chromophore in rhodopsin has been reported on studies with 11-cis-locked chiral retinal analogues (1) with 3/7 membered ring system by Prof. Nakanishi et al. Columbia University. However, the absolute configuration of 1 disagrees with that obtained by the CD calculation. To determine the absolute stereochemistry of 1 in an unambiguous manner, we have applied "the chiral phthalic acid method" to 3/7 membered alcohol. Bicyclo [5.1.0] octan-2,6-diol (syn-2) was condensed with chiral dichlorophthalic acid (-)-3 to yield a diastereomeric mixture of esters (4), which was easily separated by HPLC on silica gel. p-Bromobenzoate (+)-(5) prepared from ester 4B crystallized as single crystals suitable for X-ray diffraction. The (1S, 2R, 7R) configuration of (+)-(5) was unambiguously determined by the X-r … More ay Bijvoet method.2. As the fundamental information of bioactive compounds and chiroptically active organic materials recently developed, we are constructing the chirality database, "Chiral World." To collect many CD data, we have invited Prof. Kuball, University of Keiserslautern, and also sent Prof. Harada there, and we have developed the CD database format to normalize these data.3. As the joint work with Prof. Pirkle, University of Illinois, various o-substituted diaryl methanols were enantioresolved by the chiral phthalic acid method as follows ; (1) esterification of racemic alcohols with chiral phthalic acid, (2) separation of a diastereomeric mixture of the esters formed by HPLC on silica gel, and (3) recovery of enantiopure alcohols from the separated esters. The absolute configurations of chiral phthalic acid esters of o-substituted diaryl methanols were unambiguously determined by the X-ray crystallography using the campharsultam moiety as the internal standard of absolute configuration. Less