INTERMEDIATE PRODUCT FOR THE PRODUCTION OF 6,7- DIMETHOXY-4-AMINO-2-¬4-(2-FUROYL)-1- PIPERAZINYLQUINAZOLINE HAVING AN ANTIHYPERTENSIVE EFFECT

摘要

ABSTRACT OF THE DISCLOSUREAnovel benzonitrile, namely 3,4-dimethoxy-6-[4-(2-furoyl)-1-piper-azinylthiocarbamide] benzonitrile is provided herein. It may be prepared bycarrying out one of the following reaction, namely (a) reacting 3,4-dimethoxy-6-aminobenzonitrile having the formula(IV)with thiophosgene, to form 3,4-dimethoxy-6-isothiocyanatobenzonitrile havingthe formula(V)and then reacting compound (V) with 1-(2-furoyl)piperazine having the formula(VI)or (b) reacting 1-(2-furoyl)piperazine (Formula VI) with thiophosgene toform 4-(2-furoyl)-piperazinylthiocarbonyl chloride having the formula(VII )and then reacting compound (VII) with 3,4-dimethoxy-6-amlnobenzonitrile(Formula (IV). The product is an intermediate in the production of theanthibypertensive drug prazosine by a process in which the formation of thequinazoline ring of prazosine occurs within the molecule.