A New Efficient Method for Conversion of Corticosteroid 17α, 21-Cyclic Ortho Esters to 17α-Acyloxy-21-chloro-21-deoxy Derivatives

Abstract

The reaction of corticosteroid 17α, 21-cyclic ortho esters (2) with various chloroformates (3) afforded the corresponding 17α-acyloxy-21-chloro-21-deoxy derivatives (4) in good yields. It was found that several new derivatives, 17α-acyloxy-21-chloro-11β-hydroxy-6α-methyl-1, 4-pregnadiene-3, 20-diones (4a-g), exhibited potent vasoconstrictive activities.