Chemical synthesis of 3β-sulfooxy-7β-hydroxy-24-nor-5-cholenoic acid: An internal standard for mass spectrometric analysis of the abnormal Δ5-bile acids occurring in Niemann-Pick disease
作者:Genta Kakiyama、Akina Muto、Miki Shimada、Nariyasu Mano、Junichi Goto、Alan F. Hofmann、Takashi Iida
DOI:10.1016/j.steroids.2009.04.007
日期:2009.9
In Niemann-Pick disease, type C1, increased amounts of 3 beta,7 beta-dihydroxy-5-cholenoic acid are reported to be present in urinary bile acids. The compound occurs as a tri-conjugate, sulfated at C-3, N-acetylglucosamidated at C-7, and N-acylamidated with taurine or glycine at C-24. For sensitive LC-MS/MS analysis of this bile acid, a suitable internal standard is needed. We report here the synthesis of a satisfactory internal standard, 3 beta-sulfooxy-7 beta-hydroxy-24-nor-5-cholenoic acid (as the disodium salt). The key reactions involved were (1) the so-called "second order" Beckmann rearrangement (one-carbon degradation at C-24) of hyodeoxycholic acid (HDCA) 3,6-diformate with sodium nitrite in a mixture of trifluoroacetic anhydride and trifluoroacetic acid, (2) simultaneous inversion at C-3 and elimination at C-6 of the ditosylate derivatives of the resulting 3 alpha,6 alpha-dihydroxy-24-nor-5 beta-cholanoic acid with potassium acetate in aqueous N,N-dimethylformamide, and (3) regioselective sulfation at C-3 of an intermediary 3 beta,7 beta-dihydroxy-24-nor-Delta(5) derivative using sulfur trioxide-trimethylamine complex. Overall yield of the desired compound was 1.8% in 12 steps from HDCA. (C) 2009 Elsevier Inc. All rights reserved.
The First Total Synthesis of Solomonsterol B, a Marine Pregnane X Receptor Agonist
agonist solomonsterol B, a natural product isolated from the marine sponge Theonella swinhoei, has been developed starting from commercially available hyodeoxycholic acid. The synthesis features a one-carbon side chain degradation and the refunctionalization of the A and B rings to install the desired trans junction and the two hydroxy groups at C2 and C3 in a trans relationship. The protocol proceeded
已从市售猪脱氧胆酸开始开发了一种获得孕烷 X 受体 (PXR) 激动剂 solomonsterol B(一种从海洋海绵 Theonella swinhoei 中分离的天然产物)的简明途径。该合成的特点是单碳侧链降解和 A 环和 B 环的再官能化,以安装所需的反式连接和 C2 和 C3 上的两个羟基,形成反式关系。该方案取得了良好的产率(13 个步骤中的 10%),还允许制备侧链修饰的衍生物,可用于 PXR 的初步构效关系。solomonsterol B 的药理学特性表明,该化合物在反式激活试验中是 PXR 激动剂,当它与肝细胞一起孵育时,它增加了 PXR 调节基因的表达。