摘要 |
Paricalcitol, a synthetic vitamin D analog, is purified to a purity greater than 99.7% by crystallization from solution in isopropyl acetate solvent, followed by filtration and vacuum drying. Isopropyl acetate appears to be unique among commonly available and pharmaceutically acceptable solvents in its ability to precipitate paricalcitol in this high purity, essentially free of isomers thereof. (see formula 1) |