Structural evolution of the quinqzoline as effective agents in the treatment of microbial infe ctions. Novel quinqzoline based thiosemicarbazide and styryl derivatives have been designed and synthesized. The structures of the synthesized compounds were assigned on the basis of elemental analysis, IR, 1H NMR. spectral data. All the newly synthesized compounds were screened against various strains of bacterial and fungi.it has been observed that compounds gave significant co-relation.