Synthesis of 16α-amino-pregnenolone derivatives via ionic liquid-catalyzed aza-Michael addition and their evaluation as C17,20-lyase inhibitors
Aza-Michael addition of 16-dehydropregnenolone was studied in the presence of a basic ionic liquid, [DBU][OAc] as catalyst and solvent. The reaction was carried out using different primary and secondary amines as N-nucleophiles. The products were obtained in moderate to good yields and were characterized by 1H and 13C NMR, MS and IR. The ionic liquid was found to be an efficient and recyclable catalyst that was reused five times. The products were investigated for the inhibition of in vitro C17,20-lyase activity and displayed moderate inhibitory effect.