摘要 |
A process for producing 7 alpha -acetylsteroids having the formula (I), in which R1, R2, R3 and R4 are hydrogen or (a) is the group (b) and (c) is the group (d). The process is characterized by the fact that a 3-oxo-17 alpha -pregna-4,6-dien-21,17-carbolacton having the formula (II), in which R3 and R4 have the meaning already described, is transformed with thioacetic acid in the presence of acids of Lewis. |