Nine biologically important pyrimidine derivatives have been prepared by conventional method and UV-irradiation methods. The percentage yield of a product was substantially higher (40%-88%) by UV-irradiation method compared to that (18%-51%) by conventional method. Moreover, the UV-irradiation method is an environmentally friendly method and avoids the pollution problem in organic synthesis. The structures of the compounds were verified by microanalysis (CHN), Infrared (IR) and Proton Nuclear Magnetic Resonance (1H-NMR) spectroscopies and X-ray powder diffraction analysis. The investigated compounds consist of a pyrimidine ring and two benzene rings with intermolecular N–H---N interaction between the adjacent molecules. The compounds crystallized in the monoclinic space group P-1. The synthesized products have also been tested for their anti-bacterial/anti-fungal and anti-oxidant activities. The compounds have shown comparatively higher activities against the fungal microbes as compared to the gram positive and gram negative bacteria. The products exhibited excellent anti-oxidant potential which was rendered to the presence of multi-chloro groups on the phenyl rings.