Process for the preparation of a stable modification of torasemide, and medicaments containing torasemide

摘要

The present invention provides a process for the preparation of cystalline torasemide in the pure modification I (monoclinic, space group P21/c, melting point 162 DEG C.) from torasemide of modification II (monoclinic, space group P2/n, melting point 169 DEG C.), wherein a suspension of torasemide of modification II is stirred in water with the addition of a catalytic amount of modification I until the rearrangement is complete. The present invention also provides pharmaceutical compositions containing torasemide of modification I.