Synthesis of some functionalized 3-(4-thioxo-3,4-dihydroquinazolin-2-Yl) acrylic acid of pharmaceutical interest

3-(4-Thioxo-3,4-dihydroquinazolin-2-yl)acrylic acid 1 proved to be a convenient precursor for the synthesis of novel polyfunctional quinazoline derivatives of pharmaceutical interest via its treatment with some, pi-deficient compounds such as phenyl isocyanate and phenyl isothiocyanate. Also, S- and N-glucosidation of quinazoline has been achieved by treatment of 1 with glucopyranosyl bromide in alkaline medium. The behavior of 1 toward acrylonitrile (under Michael reaction condition), paraformaldehyde in the presence of secondary amines (under Mannich reaction condition) and sodium azide were investigated. Moreover, the peptidyl derivatives of quinazoline have been synthesized by condensation of 1 with alpha-amino acids via different routes. Some of the newly synthesized products were tested for their antimicrobial activities. The structure assignments are based on the analytical and spectroscopic results.