New series of quinazolinone derived Schiff’s bases: synthesis, spectroscopic properties and evaluation of their antioxidant and cytotoxic activity

Abstract

A series of novel 2,3-di-substituted-2,3-dihydro-quinazolin-4(1H)-one derived Schiff’s bases (1–7) have been designed, synthesized and characterized on the basis of their physical and spectral data. The presented microwave-assisted, phosphomolybdic acid (PMoA) catalysed, protocol provides an efficient and convenient route for the synthesis of structurally diverse and potentially biologically active compounds. The molecular structures of these Schiff’s bases related to quinazolinones were confirmed by various spectroscopic methods (NMR, FTIR, UV–Vis) and their antioxidant activities were evaluated by UV–Vis and EPR spectroscopy employing 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assay. Derivatives 1–7 were examined for their cytotoxicity in vitro against human hepatocellular carcinoma cells (HepG2) using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphentltetrazolium bromide (MTT) assay. The structure–activity relationships study revealed that the position and nature of functional groups attached to the quinazolinone moiety alter their physico-chemical and biological properties. Derivatives 5, 6 and 7 bearing multiple electron-donating groups were found to be the most active members of this series.