New, stable crystalline polymorph (form III) of the diuretic torasemide, by controlled acidification of alkaline solutions, has more rapid dissolution than form I

摘要

New crystalline polymorph of torasemide, characterized by its powder x-ray diffraction pattern data; and its preparation by controlled acidification of alkaline torasemide solutions at specific temperatures and over specific periods. New crystal modification (form III) of torasemide, with spacings (d) between lattice planes, expressed in angstroms as 15.3898, 12.5973, 11.4565, 9.7973, 9.5493, 8.6802, 8.2371, 7.6351, 7.3356, 6.9759, 6.5351, 6.3240, 6.1985, 5.9521, 5.6237, 5.5623, 5.4040, 5.1119, 4.8738, 4.7865, 4.6986, 4.5985, 4.4602, 4.3405, 4.2552, 4.1829, 4.0768, 3.9377, 3.8659, 3.8429, 3.7801, 3.7248, 3.6239, 3.5556, 3.4825, 3.4130, 3.3055, 3.2298, 3.1786, 3.1278, 3.0699, 3.0078, 2.9549, 2.9056, 2.8541, 2.7686, 2.6988, 2.6610, 2.6293, 2.5549, 2.5236, 2.4485, 2.4161, 2.3671, 2.3133, 2.2788, 2.2312, 2.1852, 2.1468, 2.0957, 2.0617, 2.0273, 1.9896, 1.9688, 1.9274, 1.8853, 1.7931, 1.7449, 1.7169, 1.6512, 1.6122, 1.5601, 1.5320, 1.5057, 1.4521, and 1.3773. An independent claim is also included for the preparation of this new modification form III, by controlled acidification of an alkaline torasemide solution with inorganic or organic acids, with or without addition of a seed crystal, at a temperature of 0-35[deg]C within a period of 0.25-25 hours. ACTIVITY : Diuretic; cardiovascular; hypotensive; cardiant; ophthalmological; cytostatic; anticonvulsant; antiallergic; antiasthmatic. MECHANISM OF ACTION : None given.