| abstract |
The invention comprises compounds of formula <FORM:0983125/C2/1> wherein X is a chlorine or bromine atom and R is a hydrogen atom or an acyl group, and the process for preparing 9(11)-dehydro-12-desoxyspirotanes by reducing a 9(11)-dehydro-12-ketospirostane to the corresponding 12-(a - or b -hydroxy)-spirostane or a mixture of the epimers and, if desired, converting this to the 12-acylate, converting this product to the corresponding 12-halospirostane of the invention, and reducing this product to the 9(11)-dehydro-12-desoxyspirostane Starting materials specified are 9(11)-dehydrohecogenin, the 3-acyl derivative thereof, and 9(11)-dehydrobotogenin. |