Perimidines or 1H-perimidines represent an important class of heterocyclic compounds built up of a dihydropyrimidine ring peri-fused to a naphthalene moiety. They exhibit 1, 3-annular tautomerism due to two possible hydrogen positions at one or the other endocyclic nitrogen atoms or both resulting in the imine or enamine forms, respectively. The imine forms of 2- substituted-1H-perimidines can exhibit cis or trans orientation of 2-substituent in respect of ...
