从珠子草中分离得到的化合物:软木三萜酮在溶液和晶体中的结构

首次从大戟科植物珠子草中分离得到软木三萜酮.利用晶体X-射线法与一维和二维核磁共振法测定了该化合物的结构,指认了核磁共振信号的归属.晶体衍射结果表明,化合物是以斜方晶体空间群形成晶体,晶体数据维P2(1)2(1)2(1)with a=6.361(2)A,b=13.933(3)A,c=28.440(6)A,α=90°,β=90°,γ=90°,V=2520.6(11)A3,Z=4.在晶体中存在一个微弱的分子间的作用力C-H……O=C,此作用力被认为是晶体形成的重要因素.NMR方法确定化合物的结构相同,表明了软木三萜酮在晶体和溶液具有相同的构型.

THE STRUCTURES IN CRYSTAL AND IN SOLUTION OF FRIEDELIN ISOLATED FROM PHYLLANTHUS NIRURI LINN

Friedelin was first isolated from Phyllanthus niruri linn. Its structure was determined by means of spectroscopy methods and X-ray crystallography. Chemical shifts of all carbons and protons were assigned based on the 2D NMR methods. The structure elucidated by means of NMR coincided with the structure got from X-ray diffraction method. It means that structure of friedelin in crystal an in solution have a same configuration. This compound crystallized in the orthorhombic space group P2(1)2(1)2(1) with a = 6.361(2)A, b = 13.933(3)A, c = 28.440 (6)A, α = 90°,β= 90°, γ= 90°,V = 2520.6(11)A3,Z= 4.A slightlyintermolecular contact C-H O=C was observed firstly in this crystal. This contact was supposed to be the determinative factor of formation of the crystal.