| 摘要 |
PROBLEM TO BE SOLVED: To provide a novel crystal polymorphism of levonorgestrel which is a steroid useful as an emergency contraceptive or the like, and to provide a production method thereof, as well as to provide a pharmaceutical composition containing the crystal polymorphism.SOLUTION: The invention provides: a &bgr;-crystal polymorphism of levonorgestrel in which a diffraction angle 2&thetas; has a diffraction peak at 2&thetas;=13.9° ±0.2°, 14.5° ±0.2°, 21.3° ±0.2°, 24.9° ±0.2°, and 28.2° ±0.2° in powder X-ray diffraction spectrum; and a pharmaceutical composition containing the crystal polymorphism. The diffraction peak is not substantially shown at 2&thetas;=18.6° ±0.2°, and when the strength of the diffraction peak at 2&thetas;=13.9°±0.2° is Xand the strength of the diffraction peak at 2&thetas;=14.5°±0.2° is X, X/X=5/100-2000/100. The invention also provides a method for producing the &bgr;-crystal polymorphism by mixing a dioxane solution of levonorgestrel with hexane as a deposition solvent. |
