20-(5,5-dimethyl-1,3-dioxan-2-yl)-1alpha-(tert-butyldimethylsilyl)oxy-3beta-(N,N-dimethylcarbamoyl)oxypregn-6-en-5alpha-ol → 20-(5,5-dimethyl-1,3-dioxan-2-yl)-1alpha-(tert-butyldimethylsilyl)oxy-3beta-(N,N-dimethylcarbamoyl)oxypregna-5,7-diene

Participants

Reaction Steps

In 10 ml of benzene was dissolved 350 mg of 20-(5,5-dimethyl-1,3-dioxan-2-yl)-1α-(tert-butyldimethylsilyl)oxy-3β-(N,N-dimethylcarbamoyl)oxypregn-6-en-5α-ol, followed by addition of one drop of concentrated sulfuric acid. The mixture was stirred in an atmosphere of argon gas under ice-cooling for 1 hour. The reaction mixture was then worked up in the same manner as Example 124 to give 135 mg of 20-(5,5-dimethyl-1,3-dioxan-2-yl)-1α-(tert-butyldimethylsilyl)oxy-3β-(N,N-dimethylcarbamoyl)oxypregna-5,7-diene showing the following properties.

Provenance & Evidence