Synthesis, structural characterization and biological properties of cyclometalated iridium(III) complexes containing 2-methyl-3-{(E)-[(quinolin-2-yl)methylidene]amino}quinazolin-4(3H)-one

•Two cyclometalated iridium(III) complexes were synthesized and characterised.•The complex 2 was characterized by single crystal X-ray structure determination.•The iridium(III) complexes have weak DNA binding ability.•Iridium(III) complexes have higher cytoxicity than cis-platin.•The iridium(III) complexes undergo rapid cellular internalization and localized throughout the cells.