Bowen S T, Parish E J, Wilson W K, Schroepfer G J, Quiocho F A
Department of Biochemistry, Rice University, Houston, TX 77251.
Chem Phys Lipids. 1988 Apr;46(4):245-51. doi: 10.1016/0009-3084(88)90038-2.
The chemical synthesis of 3 beta-p-bromobenzoyloxy-15 beta-methyl-5 alpha,14 beta-cholest-7-en-15 alpha-ol from 15 beta-methyl-5 alpha, 14 beta-cholest-7-ene-3 beta,15 alpha-diol is described. The structure of the former compound was unambiguously determined by X-ray crystallographic analysis. The space group of the crystal was P2 with unit cell parameters a = 12.611 A, b = 9.826 A, c = 13.221 A, b = 91.71 degrees and Z = 2. The structure was solved by the heavy atom method and refined to a final R of 0.041. Asymmetry parameters indicated that ring A is a symmetrical chair, that rings B and C are half chairs, and that ring D is a 15 alpha-envelope.
描述了由15β-甲基-5α,14β-胆甾-7-烯-3β,15α-二醇化学合成3β-对溴苯甲酰氧基-15β-甲基-5α,14β-胆甾-7-烯-15α-醇的方法。通过X射线晶体学分析明确确定了前一种化合物的结构。晶体的空间群为P2，晶胞参数a = 12.611 Å，b = 9.826 Å，c = 13.221 Å，β = 91.71°，Z = 2。采用重原子法解析结构并精修至最终R值为0.041。不对称参数表明A环为对称椅式，B环和C环为半椅式，D环为15α-信封式。
