5β-Pregnane-3α, 20β-diol Disulfateの3N塩酸煮沸による分解について : ステロイドの臨床分析(第26報)

抄録

The degradation of 5β-pregnane-3α, 20β-diol disulfate (2) by refluxing with 3N hydrochloric acid was investigated. In addition to the main product, 17α-methyl-D-homo-5β-androstane-3α, 17aβ-diol (5), various kinds of minor degradation products were detected by gas chromatography and their structures were determined by gas chromatography-mass spectrometry as : 17α-methyl-17aβ-chloro-D-homo-5β-androstan-3α-ol (6), 17α-ethyl-17β-methyl-5β-androst-13-en-3α-ol (7), 5β-pregn-20-en-3α-ol (8), E-isomer (9) of 5β-pregn-17 (20)-en-3α-ol, 5β-pregn-3-en-20β-ol (13), 5β-pregn-2-en-20β-ol (14), and pregnanediol (3). The D-homoannulation of 2 to give 5 and 6 was considered to occur mainly by a concerted mechanism, while stepwise mechanism involving C₂₀-carbonium ion was assigned to the formation of the minor products. Stereochemistry of the degradation of 2 by hot acid is discussed.