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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1067914Generated: November 1, 2026

Ethanol → Terazosin

https://huagongshe.com/reaction/1067914

Reaction equation

Participants

RoleNameHCIDCharge
ReactantEthanolHCID 702—
Reactant2-Chloro-6,7-dimethoxy-4-quinazolinamineHCID 90235—
Reactant1-(Tetrahydro-2-furoyl)piperazineHCID 2734641—
SolventWaterHCID 962—
ProductTerazosinHCID 5401101.5%

Reaction Steps

To a solution of absolute ethanol (272 ml), water (68 ml) and N-(2-tetrahydrofuroyl)piperazine (20 g) were added, while stirring, 4-amino-2-chloro-6,7-dimethoxyquinazoline (22.2 g). The reaction mixture was heated to reflux and the reflux was maintained for about 32 hours. Then the reaction mixture was cooled to room temperature and stirred at this temperature for about 48 hours. The crystals were collected by filtration, washed with absolute ethanol and dried in vacuo at 40° C. to yield 36.44 g (85.5%) of Terazosin.HCl dihydrate. See Trial M in Table I. Trial N was performed using a 10% volume of water.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS06248888B1
Source datasetuspto-grants-2001_06
ORD IDord-6974a168f6cd404a8e52a190cb51185e
Source noteuspto-grants-2001_06