The pharmacological activity of several 16-bromosubstituted trienediones 4 and 5, 16-methyl substituted dienediones 6 and 7 and the 16-methyl substituted trienedione 8 was determined on gonadectomized hamster seminal vesicles by measuring the in vitro conversion of testosterone (T) to dihydrotestosterone (DHT) as 5α-reductase inhibitors and also the ability of these steroids to bind to the androgen receptor. Steroids 6 and 7 when injected together with T decreased the weight of the seminal vesicles thus showing an antiandrogenic effect. Compounds 5 and 6 reduced substantially the conversion of T to DHT and therefore can be considered good inhibitors for the enzyme 5α-reductase; however both steroids failed to form a complex with the androgen receptor. On the other hand compound 7 which showed a very small inhibitory activity for the enzyme 5α-reductase, exhibited a very high affinity for the androgen receptor and thus can be considered an effective antiandrogen. This compound also reduced substantially the weight of the seminal vesicles. Steroids 4 and 8 did not reduce the weight of the seminal vesicles and exhibited a low affinity for the androgen receptor; 8 showed a weak 5α-reductase inhibitory activity, whereas 4 exhibited a weak androgenic effect.
通过测量
睾酮(T)在体外转化为双氢
睾酮(DHT)的情况,以及这些类
固醇与雄激素受体结合的能力,确定了几种16-
溴取代
三烯二酮4和5、16-甲基取代二烯二酮6和7以及16-甲基取代
三烯二酮8在去势仓鼠精囊中的药理活性,它们是5α-还原酶
抑制剂。类
固醇6和7与T一起注射时,精囊重量减轻,因此显示出抗雄激素作用。化合物5和6大大减少了T向DHT的转化,因此可以被认为是5α-还原酶的良好
抑制剂;然而这两种类
固醇都无法与雄激素受体形成复合物。另一方面,化合物7对5α-还原酶的抑制活性非常小,但对雄激素受体的亲和力却非常高,因此可以被认为是有效的抗雄激素。这种化合物还大大减轻了精囊的重量。类
固醇4和8没有减轻精囊的重量,对雄激素受体的亲和力也很低;8显示出微弱的5α-还原酶抑制活性,而4则显示出微弱的雄激素作用。