Δ4-3-keto, Δ1,4-3-keto and 3β-hydroxy-17-keto-steroids are transformed into the corresponding 16β-methyl-17-keto--steroids by activating the C-16 position, methylating, and reacting with a strong base. The C-3 position of the Δ4-3-keto and 3β-hydroxy-steroids is protected.
Δ4-3-酮、Δ1,4-3-酮和 3β-hydroxy-17-keto-steroids 通过活化 C-16 位、甲基化并与强碱反应,转化为相应的 16β-甲基-17-
酮类化合物。Δ4-3-
酮类和 3β- 羟基类
固醇的 C-3 位受到保护。