Expedient synthesis of lactone analogues of formestane as new potential aromatase inhibitors

Abstract

A convenient synthetic strategy for the preparation of ring-D lactones of the androstane derivatives 4, 5 and 6 has been achieved through a high yielding, three-step sequence. Baeyer–Villiger oxidation of 3α,4β-dihydroxy-5α-androstan-17-one 3, previously prepared from a 3-olefin, followed by a TFAA mediated Swern oxidation and subsequent isomerization allowed the preparation of the ring-D lactone analogue of formestane 6.