Design and synthesis of three Fe(III) mixed-ligand complexes: Exploration of their biological and phenoxazinone synthase-like activities

•New Fe complexes based on Schiff-base & N-heterocyclic ring have been assembled.•DFT calculations were performed to estimate the electronic properties.•The complexes showed a promising antibacterial and antifungal activity.•Phenoxazinone synthase mimicking activity was explored.•Structure activity relationship (SAR) for these complexes had been derived.