| 摘要 |
The invention concerns a method of preparing 14,17(alpha)-etheno- and 14,17(alpha)-ethano-16(alpha),17(beta)-steroiddiols and derivatives thereof, in particular 14,17(alpha)etheno- and 14,17(alpha)-ethano-3,16(alpha),17(beta)-estriols and their esters, which are highly active, orally effective oestrogens, by Diels-Alder addition of a vinyl ester, preferably vinyl acetate, to a 17-alkanoyloxy-14,16-diene. |
