PhI=NSes mediated aziridination of 11-pregnane derivatives: Synthesis of an 11,12-aziridino analogue of neuroactive steroids

Article abstract of DOI:10.1016/S0040-4020(02)01655-1

Reaction of 11-pregnene-3,20-dione (6) or 3-α-acetoxy-11-pregnen-20-one (12) with trimethylsilylethanesulfonyl ('Ses') iminoiodinane 5 in the presence of copper (I) triflate gave the corresponding α,α-11,12-aziridino steroids 7 and 13 in 53 and 45% yields, respectively. The Ses group of each compound was removed using the TASF reagent and the resulting free aziridine NH was methylated to afford the 11α,12α-N-methyl aziridinosteroids 9 and 15, respectively. The latter is a conformationally constrained analogue of the endogenous neurosteroid pregnanolone (1).