One pot cyclocondensation reaction of barbituric/thiobarbituric acid with aromatic aldehydes and p-phenylenediamine/2, 6-diaminopyridine by refluxing in glacial acetic acid afforded novel bis (pyrimido [5, 4-c] quinoline-2, 4 (1H, 3H)-diones)/pyrido bis (pyrimido [5, 4-c] quinoline-2, 4 (1H, 3H)-diones. All the synthesized compounds were screened for their antioxidant activities using FRAP and DPPH methods. Compounds with chloro ...