Condensation of 2-aminobenzimidazole, ortho-substituted benzaldehydes and cyclohexanone proceeds with the formation of 10-o-Rsubstituted phenyl benz[4,5]imidazolo-6,7,8,9,10,11-hexahydro[1,2-a] quinazolines having angular articulation rings, strukture which is set using IR, NMR, 1 H, 13C spectra.