Synthesis and Antimicrobial Activity of Some Novel Hydrazinyl Quinazoline Amine Derivatives

2-chloro-4-aminoquinazolines 3a-b were synthesized by intramolecular cyclization of substituted formamide 2a-b in presence of phosphorus oxychloride in one pot. These were further condensed with 5-aryl/alkyl-2-hydrazino-1,3,4thiadiazoles 8a-e. synthesized by condensation of hydrazine hydrate with 2-chloro-5-aryl/alkyl-1,3,4-thiadiazoles 7a-e which in turn were obtained by copper mediated diazotization of 2-amino-5-aryl/alkyl-1,3,4-thiadiazoles 6a-e in acetic acid to give various 2-[2-(1,3,4-thiadiazol-2-yl)hydrazinyl] quinazolin-4-amines 9a-l. The structures of the compounds have been confirmed by elemental analysis and spectral analysis. Newly synthesized compounds were screened for their antimicrobial activities.