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

用x射线晶体学和圆二向色法测定了各种手性有机化合物的绝对立体结构。我们明确了CD激子手性方法适用于含有两种或两种以上不同发色团的非简并体系，并确定了以下具有生物活性的天然产物和人工合成的手性有机化合物：含有蒽类发色团的三烯体系；从海藻中分离出的一种甾烷二萜的异氨基jiol；不饱和羟基脂肪酸——水稻抗稻瘟病的自卫物质具有角保护羟基的旋光性威兰-米歇尔酮类似物；致癌苯并[e]芘衍生物；反式- 2,3 -二取代螺环丙烷-1,9'-芴衍生物；2, 2’-spirobibenz [e]茚满衍生品;由d -亮氨酸合成的手性甾体cd环。此外，我们还建立了测定无环二醇绝对立体结构的CD方法。有许多天然产物具有扭共轭<pi> -电子体系。我们发现，用<pi> -电子scf - ci -偶极子速度MO法理论计算CD光谱对于确定这类化合物的绝对立体结构是非常有用的。例如，我们成功地确定了(+)-1,8a-二氢-3,8-二甲基噻唑烯的绝对立体结构，这是一种从一种茅中分离出来的1,4-二甲基噻唑烯的稳定的生物合成中间体。通过合成合适的手性模型化合物，验证了理论结论。应用该方法，确定了下列具有扭曲共轭<pi> -电子体系的化合物的绝对立体结构：新型手性对流层样螺旋化合物；冲绳海绵的一种心脏活性成分、烯丙酚及其衍生物；顺式和反式4,4′-联苯苯基的手性烯烃。x射线方法和CD方法是互补的，通过x射线晶体学研究建立了二氢偶氮烯模型化合物合成中间体的绝对立体化学，证明了两种方法的一致性。少

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