The present study involves one pot synthesis of a novel Schiff base derived from 2‐hydroxy‐1‐naphthaldehyde. Further the Schiff base is used for metal complex preparation. All synthesized compounds are characterized by various spectral and analytical studies. Stoichiometry of the complexes is confirmed by Job's plot method. Of the three complexes, Co(II) complex is found to be the most stable one through UV/Vis titrations and Benesi‐Hildebrand equation. Redox property of the complexes ascertained from CV(Cyclic Voltammetry) confirms catalytic application of the complexes; while fluorescence property of the complexes and the Schiff base indicates chemosensor application of the Schiff base. Both the Schiff base and the complexes are screened against bacterial and fungal pathogens. MIC (Minimum Inhibitory Concentration) studies of the Schiff base and the cobalt complex over Staphylococcus aureus disclose the MIC value as 25 ppm. Cu(II) complex is found to have cytotoxicity against breast cancer cell lines (MCF‐7).