[EN] PROCESS FOR THE PREPARATION OF HIGHLY PURE TORSEMIDE<br/>[FR] METHODE DE PREPARATION DE TORSEMIDE DE PURETE ELEVEE
申请人:FINETECH LAB LTD
公开号:WO2003097603A1
公开(公告)日:2003-11-27
The present invention provides a novel process for the preparation of highly pure torsemide [1] by reacting of 4-m-tolylamino-3-pyridinesulfonamide [2] with phenyl isopropylcarbamate in the presence of lithium base (F I, II). The present invention also provides a novel intermediate - torsemide lithium, also in hydrate or solvate form - which is a stable, solid compound, and may be simply isolated from the reaction mixture to give after acidification practically pure torsemide [1] without further purification steps.
Process for the preparation of torsemide and related intermediates
申请人:Che Daqing
公开号:US20050209460A1
公开(公告)日:2005-09-22
A process for preparing torsemide or salts thereof comprising: a) reacting II with isopropyl isocyanate in the presence of an alkali carbonate or bicarbonate and an organic solvent to form an alkali torsemide mixture, b) recovering the alkali torsemide mixture, and c) if desired, recovering the torsemide by acidification of the alkali torsemide mixture.