-Piperazinecarboxylic acid, 4-(6,7-dimethoxy-4-quinazolinyl)-, 2-hydroxy-2-methylpropyl ester 1-Piperazinecarboxylic acid, 4-(6,7-dimethoxy-4-quinazolinyl)-, 2-hydroxy-1-methylpropyl ester 21560-59-8 HOQUIZIL