Terazosin Hydrochloride → Terazosin Hydrochloride Anhydrous

Participants

Reaction Steps

In its principal embodiment, the present invention comprises a process for the preparation of 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(2-tetrahydrofuroyl)piperazine hydrochloride dihydrate comprising the steps of a) reacting 4-amino-2-chloro-6,7-dimethoxyquinazoline with N-(2-tetrahydrofuroyl)-piperazine in an anhydrous polar organic solvent in the absence of an added acid scavenger to produce the Form IV crystalline modification of anhydrous 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(2-tetrahydrofuroyl)piperazine hydrochloride; and b) thereafter converting the product of Step a) to 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(2-tetrahydrofuroyl)piperazine hydrochloride dihydrate.

Provenance & Evidence