Determination of Absolute Stereostructure of Organic Compounds by Means of X-Ray Crystallographic and Circular Dichroic Methods

X 射线晶体学和圆二向色法测定有机化合物的绝对立体结构

基本信息

批准号：
59430005
负责人：
HARADA Nobuyuki
金额：
$ 15.62万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (A)
财政年份：
1984
资助国家：
日本
起止时间：
1984 至 1986
项目状态：
已结题

项目摘要

The absolute stereostructure of various chiral organic compounds were determined by means of X-ray crystallographic and circular dichroic methods. We clarified that the CD exciton chirality method is applicable to the non-degenerate systems containing two or more different chromophores, and determined the following biologically active natural products and synthetic chiral organic compounds: triptycene systems containing an anthracene chromophore; isoamijiol of a dolastane diterpene isolated from a seaweed; unsaturated hydroxy fatty acids, the self defensive substances in rice plant against rice blast disease; optically active Wieland-Miescher ketone analogues bearing an angular protected hydroxymethyl group; carcinogenic benzo[e]pyrene derivatives; trans-2, 3-disubstituted spirocyclopropane-1,9'-fluorene derivatives; 2,2'-spirobibenz[e]indan derivatives; a chiral steroid CD-ring synthon from D-leucine. Furthermore, we established the CD method for determining the absolute stereostructu … More re of acyclic glycols.There are many natural products having a twisted conjugated <pi> -electron system. We have found that for determination of absolute stereostructure of such compounds, the theoretical calculation of CD spectra by the <pi> -electron SCF-CI-dipole velocity MO method is very useful. For instance, we succeeded to determine the absolute stereostructure of (+)-1,8a-dihydro-3,8-dimethylazulene, a labile biosynthetic intermediate for 1,4-dimethylazulene isolated from a liverwort, by calculation of CD spectra using the present MO method. The theoretical conclusion was experimentally proved by the synthesis of suitable chiral model compounds. By applying this method, the absolute stereostructures of the following compounds having a twisted conjugated <pi> -electron system were determined: novel chiral troponoid spiro compounds; a cardiac active constituent of an Okinawan marine sponge, halenaquinol and its derivative; chiral olefins of cis- and trans-4,4'-biphenanthrylidenes. The X-ray and CD methods are complementary each other, and the absolute stereochemistry of the synthetic intermediate of the dihydroazulene model compounds was established by the X-ray crystallographic studies, proving that both of the methods are consistent with each other. Less

各种手性有机化合物的绝对立体结构是通过X射线晶体学和圆形二色性方法确定的。我们澄清说，CD令人兴奋的手性方法适用于包含两个或更多不同发色团的非分类系统，并确定了以下生物活性的天然产物和合成手性有机化合物：含有蒽色粒的三倍苯树系统；从海藻中分离出的dolastane ditrene的异硫醇；不饱和羟基脂肪酸，水稻植物中针对水稻爆炸疾病的自我防御性物质；具有角度保护的羟基甲基的光学活性Wieland-Miescher酮类似物；致癌苯并[E] pyrene衍生物； Trans-2，3分取代的螺旋丙烷1,9'-氟衍生物； 2,2'-Spirobenz [e] indan衍生物； D-达氨酸的手性类固醇CD形环合成。此外，我们还建立了CD方法，用于确定绝对的定位构结构……更多的无环乙二醇。有许多天然产品具有扭曲的共轭<pi> - 电子系统。我们发现，为了确定此类化合物的绝对立体结构，通过<pi> - 电子SCF-CI-CI-偶极速度MO方法对CD光谱的理论计算非常有用。例如，我们成功地确定了（+） - 1,8a-dihydro-3,8-二甲基硫酸盐的绝对立体结构，这是一种使用当前的MO方法计算CD光谱的1,4-二甲基硫酸元的不稳定生物合成中间体。通过合成合适的手性模型化合物的合成，实验证明了理论结论。通过应用此方法，确定了具有扭曲连接的<pi> - 电子系统的以下化合物的绝对立体结构：新型手性troponoid螺旋体化合物；冲绳海洋赞助商Halenaquinol及其衍生物的心脏活跃构成；顺式和trans-4,4'-二烯乙烯乙烯的手性烯烃。 X射线和CD方法相互完成，并且X射线晶体学研究确定了二氢余心素模型化合物的合成中间体的绝对立体化学化学化合物，前提是这两种方法都是彼此一致的。较少的