Regioselective synthesis of novel 5-nitro-naphthoquinone derivatives: Electrochemistry and in-situ spectroelectrochemistry properties

•Naphthoquinones have the ring system as important core structure in drug substances.•Aromatic ring with NO2 in quinone system is known to increase biological activity.•Redox reactions of quinones are important in biological and material fields.•Electrochemical studies were carried out to perform assignments of the redox reactions.•This is the first in-situ UV–Vis spectroelectrochemical study for 5-Nitro-NQ’s.