X-射线单晶衍射法研究双炔失碳醇α-差向异构体的构型

本文报道有抗生育作用和雌激素活性的双炔失碳醇α-差向异构体的构型研究。采用重结晶法、低压硅胶柱色谱与HPLC相结合的方法,制得单晶纯品。经HPLC,IR,MS,¹HNMR证实。经Ⅹ-射线单晶衍射法测定,晶体属正交晶系,空问群为P222₁,晶胞参数为a=6.777(2),b=12.125(4),c=25.292(8),V=2078.5(1.2)。晶体结构采用直接法和Fourier技术得到,经最小二乘法修正,最后的偏离因子R=0.039。结构表明:其相对构型中,C₂,C¹⁷之乙炔基为α-型,结合合成原料构型推定C₂为R型,C₁₇为R型。

X-ray diffraction studies on the configuration of 2 xi, 17 alpha-diethynyl-2 xi, 17 beta-dihydroxy-A-nor-5 alpha-androstane alpha-epimer

X-ray diffraction studies on the configuration of 2 xi, 17 alpha-diethynyl-2 xi, 17 beta-dihydroxy-A-nor-5 alpha-androstane "alpha-epimer" that possessed antifertility effect and estrogen activity were reported. Pure alpha-epimer was obtained by recrystallization and low pressure silica gel column chromatography combined with HPLC method. Its structure was identified by IR, MS, 1HNMR. The configuration was determined by single crystal X-ray diffraction analysis. The crystal of alpha-epimer belonged to orthorhombic, the space group was P222(1), with the following crystallographic parameters: a = 6.777 (2), b = 12.125 (4), c = 25.292 (8)A, V = 2078.5(1.2)A3, Z = 4. One thousand two hundred and thirty-five independent reflections with I greater than or equal to 3 sigma (I) were collected on a Nicolet R3M/E four-circle diffractometer by means of MoK alpha radiation. The structure was solved by direct method and refined by least square technique to a final discrepancy factor of R = 0.039. The molecule was shown to consist of the alpha-configuration of C2 and C17ethynyl groups. The absolute configuration was deduced by the absolute configuration of synthetic raw material, conformation analysis and the study of 1HNMR. The absolute configuration of asymmetric centers were 2R,5S,8R,9S,10S,13S,14S,17R.