4α-Aminosteroids were synthesized by the substitution of a 2α-bromo ketone using K2CO3 as an activator; 4β-aminosteroids were synthesized in excellent yields by a highly regioselective and trans-stereospecific ring opening of a steroidal 3,4α-epoxide using ZnCl2âH2O as a catalyst.
采用K2CO3作为活化剂,通过2α-
溴酮的取代反应合成了4α-
氨基甾体;在ZnCl2-
H2O催化剂的作用下,通过甾体3,4α-
环氧化物的区域选择性和反式立体特异性环开裂反应,以优异的产率合成了4β-
氨基甾体。