[Potentially bioactive pyrimidine derivatives. 1. 2-Amino-4-aryl-8-arylidene-3,4,5,6,7,8-hexahydroquinazoline].

Six condensed 2-amino-4-arylpyrimidines (1a-f) were synthesized by the base catalyzed reaction of some monoarylidenecycloalkanones and guanidine. The reaction of 2,6-diarylidenecyclohexanones with guanidine yielded 2-amino-4-aryl-3,4,5,6,7,8-hexahydroquinazolines which were stable only as salts 3a-j. The oxidation of 3a-j led to 2-amino-4-aryl-8-arylidene-5,6,7,8-tetrahydroquinazolines 4a-j.