Synthesis of some New Fused Pyrimidine Compounds

Biginelli reaction is a one-pot reaction which is used to prepare some of fused pyrimidine (2-Amino-4-aryl-7, 7- dimethyl-1, 4, 5, 6, 7, 8-hexahydro quinazoline-5-one) (A1-6) by the action of dimedone, guanidenium hydrochloride and some substituted benzaldehyde in presence of Lewis acid represented by boric acid (20% mole). These compounds were used later as precursors to prepare a superim type of schiff bases represented by compounds (2-Amino-4-aryl-5-hydrazono-7, 7-dimethyl-1, 4, 5, 6, 7, 8-hexahydro quinazoline) (B1-6). The assigned structure of the prepared compounds was corroborated by available physical and spectral methods.