11-oxo estr-9-ene derivs. - intermediates in the synthesis of steroids

摘要

Cpds. of formula (I) are new (where R1 is 1-3C alkyl; R2 is oxygen, free or blocked in the form of a ketal or a gp. in which R3 is H or acyl derived from a 1-2C carboxylic acid) and are inters. in the synthesis of steroids, esp. cortisone derivs.