Patent ID: 6462031
Filing Date: 2002-10-08
Classification: C07C

Abstract:
A method of purifying 1&agr;-hydroxyvitamin D2, comprising the steps of:(a) boiling a solvent consisting of essentially of ethyl acetate under inert atmosphere; (b) dissolving a product containing 1&agr;-hydroxyvitamin D2 to be purified in said solvent; (c) adding petroleum ether to said solvent after dissolving said product in said solvent; (d) cooling said solvent and dissolved product below ambient temperature for a sufficient amount of time to form a precipitate of 1&agr;-hydroxyvitamin D2 crystals; and (e) recovering the 1&agr;-hydroxyvitamin D2 crystals having a molecular packing arrangement defined by space group C2 and unit cell dimensions a=23.9AÂ°, b=6.8AÂ°, c=31.7AÂ°, &agr;=90Â°, P=100.9Â° and y=90Â°, or any other space group that yields substantially the same crystalline packing arrangement.