(20r,25s)-2-methylene-19,26-dinor-1amp;alpha;, 25-dihydroxyvitamin d3 in crystalline form

摘要

Provided is a method of purifying (20R,25S)-2-methylene-19,26-dinor-1α,25-dihydroxyvitamin D3, depicted in formula (I), to obtain the compound in crystalline form. Further provided is a crystalline form of (20R,25S)-2-methylene-19,26-dinor-1α,25-dihydroxyvitamin D3 . The method includes preparing a solvent of methanol and water, dissolving a product containing (20R,25S)-2-methylene-19,26-dinor-1α,25-dihydroxyvitamin D3 in the solvent, cooling the solvent and dissolved product below ambient temperature for a sufficient amount of time to form a precipitate of (20R,25S)-2-methylene-19,26-dinor-1α,25-dihydroxyvitamin D3 crystals, and recovering the crystals.