Synthesis, characterization, pharmaceutical evaluation, molecular docking and DFT calculations of a novel drug (E)-5-bromo-3-(phenylimino) indolin-2-one

•Geometry optimization of the molecule have been carried out..•Complete vibrational analysis of the title compound is carried out.•HOMO–LUMO, NBO, MEP, ELF and LOL study has been theoretically performed.•UV–Vis study predicted the electronic excitations by using TD-DFT method.•Molecular docking study revealed the bioactivity of the molecule.