Doxazosin → Doxazosin Mesylate

Participants

Reaction Conditions

Reaction Steps

Doxazosin (100 gms) was charged in acetone (0.8 lit) at room temperature. The contents were stirred for 10 mins at 25-30° C. Methane sulfonic acid (23.2 ml) was charged slowly at 25-30° C. The reaction mass was heated at 35-38° C. and the temperature maintained for 2 hours. The reaction mass was cooled to 25-30° C. and stirred for 1 hour. The solid obtained was filtered and washed with acetone (100 ml). The product was dried at 55-60° C. under vacuum to obtain pure Form IV doxazosin mesylate (115-120 gms) which was characterized by XRD, IR and DSC. Purity according to HPLC: −99.89%.

Provenance & Evidence