Solid phase synthesis of 2-aminoquinazoline-based compounds

A versatile method for the solid-phase synthesis of 2-aminoquinazoline-based derivatives, 3-substituted-3,4-dihydroquinazolin-2-amines and imidazoquinazolines, has been developed. They were obtained by treating the amino group of polymer-linked amino acids with 2-nitrobenzaldehyde followed by reduction of the nitro group to an amine. Cyclization of the resulting immobilized intermediates with cyanogen bromide followed by acidic/basic cleavage yielded the desired quinazoline-based compounds in high yields and purities.