Estrone derived steroidal diepoxide: Biologically active compound and precursor of a stable steroidal A,B-spiro system

A simple approach to a stable steroidal estrone derived A,B-spiro system is reported. Treatment of estrone derived A-ring diepoxyalcohol with the Ac2O-TMSOTf system at the ambient temperature led to acetylation, while at the reflux temperature the acid-catalysed rearrangement took place affording the spiro-compound. Results of extensive in vitro and in vivo anticancer tests on the diepoxide, as well as preliminary data on the antiproliferative activity of the spiro-product against three cancer cell lines, are also presented.