Acetic Anhydride → Methylprednisolone Impurity 79

Participants

Reaction Steps

A solution of 1.0 g of 17-acetoxy-11β,21-dihydroxy-6α-methyl-1,4-pregnadiene-3,20-dione in 10 ml of pyridine is stirred with 5 ml of acetic anhydride for one hour at 0° C. Then the mixture is poured on an ice water-sodium chloride solution; the precipitate is filtered off and purified by crystallization from acetone/hexane, thus isolating 810 mg of 17,21-diacetoxy-11β-hydroxy-6α-methyl-1,4-pregnadiene-3,20-dione, mp 216° C.

Provenance & Evidence