Significant steroids: effective and general synthesis of 4 alpha- and 4 beta-amino-5 alpha-androstanes

4 alpha- Aminosteroids were synthesized by the substitution of a 2 alpha-bromo ketone using K2CO3 as an activator; 4 beta-aminosteroids were synthesized in excellent yields by a highly regioselective and trans-stereospecific ring opening of a steroidal 3,4a- epoxide using ZnCl2-H2O as a catalyst.