Isolation and Structural Elucidation of the Degradation Products of Pregnanediol Disulfate obtained by Hot Acid Hydrolysis (Clinical Analysis on Steroids. XXI)

Besides the main products, 17α-ethyl-17β-methyl-18-nor-5β-androst-13-en-3α-ol (7a), 17α-methyl-D-homo-5β-androstane-3α, 17aβ-diol (8), and 17α-methyl-17aβ-chloro-D-homo-5β-androstan-3α-ol (9), other minor degradation products of pregnanediol 3, 20-disulfate (2) were obtained under reflux in 3 N hydrochloric acid, and were structurally identified by comparison with synthetic specimens. The steroidal mono olefins isolated were 5β-pregn-3-en-20α-ol (10a), 5β-pregn-2-en-20α-ol (11a), 5β-pregn-20-en-3α-ol (12a), and 5β-pregn-17 (20)-en-3α-ol (13a). The Z-isomer of 13a, 5β-pregn-17 (20)-en-3α-ol (14a), was detected by gas chromatography and identified by gas chromatography-mass spectrometric comparison with synthetic compound. Steroidal dienes were obtained as a mixture of Δ2-and Δ3-compounds having partial D-ring structures corresponding to 7a, 12a, and 13a. Although it was a minor product, 5β-pregnane-3α, 20β-diol (16) was also obtained, and its isolation suggests the formation of a C20-carbonium ion in the course of the hydrolysis. The yield of intact steroid, pregnanediol (1), was only 18.4% of the total products obtained.