A novel series of some precursors of 6, 8-dibromoquinazolin-4(3H)-one 61-12 have been synthesized by the based catalysed cyclisation of chromenamido 51-12 with phenylhydrazine hydrate. The overall reaction was base catalysed conventional multistep process. The title compounds have been confirmed by spectral data IR, 1H NMR, 13C NMR and elemental analysis. All the synthesized target molecules were screened for gram positive, gram negative antibacterial and fungicidal activity In Vitro by disc diffusion method. The zone of inhibition measured and calculated potency. The pharmacological strength of synthesized compounds was compared with standard drug.