41834-91-7Relevant academic research and scientific papers
Production of 1-phenyl-3-cyanoureas
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, (2008/06/13)
Disclosed herein is a method for producing 1-phenyl-3-cyanoureas with the general formula: STR1 by reacting the corresponding benzamide with an alkali metal or alkaline earth metal hypohalite followed by reaction with cyanamide.
Process for preparing quinazolines
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, (2008/06/13)
2-Halo-4-aminoquinazolines are produced by a two-step process involving cyclization of 1-phenyl-3-cyanoureas or 1-phenyl-3-cyanothioureas in the presence of phosphorus halides and phosphorus oxyhalides to provide a phosphoquinazoline intermediate which is hydrolyzed to the quinazoline. Exemplary of the process is the intramolecular cyclization of 1-(3,4-dimethoxyphenyl)-3-cyanourea in the presence of phosphorus pentachloride and phosphorus oxychloride to a phosphoquinazoline intermediate which is subsequently hydrolyzed with formic acid to 2-chloro-4-amino-6,7-dimethoxy-quinazoline. The 2-halo-4-aminoquinazolines of the instant process are particularly valuable as intermediates in the preparation of 4-amino-2-(4-substituted-piperazin-l-yl)quinazolines useful in the treatment of cardiovascular disease, e.g. hypertension.
