| 摘要 |
<p>The present invention provides in a process for the production of a .DELTA.15-steroid having the general formula I (I), wherein R1 represents a hydrogen atom, a trialkyl silyl group or an acyl group and R2 represents an ethynyl group, a chloroethynyl group or a propynyl group, which comprises introducing the R2 group into the 17.alpha.position of a 17- oxo steroid having the general formula II (II), wherein Y represents a ketalised keto group and one of the ----bonds in the 4, 5-, 5, 6- or 7, 10- position is a carbon-carbon double bond and the others represent carbon-carbon single bonds and A-B represents a carbon-carbon double bond or the grouping wherein R' represents a hydrogen atom, a silyl, acyl, sulphonyl or nitro group, the improvement in which Y in formula II represents a keto group protected with ethane dithiol - (1,2) and the carbon-carbon double bond is in the 4,5-position.</p> |
