Methods for preparing vitamin D derivatives that are useful for treating psoriasis

摘要

Preparation of a compound of formula (3) by a method of carbonylating a compound of formula (2) in a solvent in the presence of an organoaluminum reagent that may be represented as (R15)nAlW3-n and a palladium catalyst under a carbon monoxide atmosphere is disclosed, wherein: R12 and R13 each represent a protecting group; R14 represents a leaving group; R15 represents an alkyl group, an aryl group, an alkenyl group or an alkynyl group; W represents a halogen atom; and n represents an integer of 1 to 3. The compound of formula (3) may be used in the preparation of Vitamin D derivatives that are useful as therapeutic agents for skin diseases such as psoriasis, and that have a reduced hypercalcemic effect. (62) Divided out of 522853