Numazawa M, Osawa Y
Steroids. 1979 Sep;34(3):347-60. doi: 10.1016/0039-128x(79)90085-0.
The synthesis of epimeric 6-bromo-4-androstene-3,17-dione (1a and 1b), 6-bromotestosterone (2a and 2b) and its acetate (3a and 3b), and 6-bromo-16 alpha-acetoxy-4-androstene-3,17-dione (5a and 5b), and 6 beta-bromo-16 alpha-hydroxy-4-androstene-3,17-dione (4) is described. The interconversions among compounds 1, 2, and 3 are also studied. The 6 beta-isomer (1b, 2b, and 3b) was epimerized to the 6 alpha-isomer (1a, 2a and 3a) in carbon tetrachloride or chloroform-methanol (9:1) and the 6 alpha-isomer was isolated by fractional crystallization from the epimeric mixture. 6 alpha-Bromo isomer 1a was also epimerized back to 6 beta-bromo isomer 1b in chloroform-methanol (9:1). Two polymorphic forms of 6 beta-bromotestosterone acetate (3b) were isolated (mp. 114--117 degrees and 138--141 degrees). The 6 beta-bromo isomers were found to be unstable in methanol and decomposed to give 5 alpha-androstane-3,6-dione derivative (6). The results of irreversible inactivation of human placental androgen aromatase with some of these 6-bromoandrogens are discussed.
本文描述了差向异构的6-溴-4-雄烯-3,17-二酮（1a和1b）、6-溴睾酮（2a和2b）及其乙酸酯（3a和3b）、6-溴-16α-乙酰氧基-4-雄烯-3,17-二酮（5a和5b）以及6β-溴-16α-羟基-4-雄烯-3,17-二酮（4）的合成。还研究了化合物1、2和3之间的相互转化。6β-异构体（1b、2b和3b）在四氯化碳或氯仿-甲醇（9:1）中差向异构化为6α-异构体（1a、2a和3a），并通过从差向异构混合物中分步结晶分离出6α-异构体。6α-溴异构体1a在氯仿-甲醇（9:1）中也会差向异构化为6β-溴异构体1b。分离出了6β-溴睾酮乙酸酯（3b）的两种多晶型物（熔点分别为114 - 117℃和138 - 141℃）。发现6β-溴异构体在甲醇中不稳定，会分解生成5α-雄甾烷-3,6-二酮衍生物（6）。讨论了其中一些6-溴雄激素对人胎盘雄激素芳香化酶不可逆失活的结果。
