This article describes the synthesis and some properties of a new phenol-based Schiff base oligomer and its metal complexes. First, Schiff base monomer, 2,3-bis[(2-hydroxy- naphtyl)methylene] diaminopyridine (HNMDAP) was synthesized by condensation of 2-hydroxy-1-naphtaldehyde with 2,3-diaminopyridine. Then, HNMDAP was oxidized to give its corresponding oligomer (OHNMDAP) in the presence of the oxidants such as H2O2, NaOCl and air in alkaline medium. Finally, OHNMDAP was converted into the chelates of some divalent metals. The resulting compounds were characterized by spectral (UV-vis and IR), thermal (TG), electrochemical (CV) techniques in addition to conductivity measurements. Both HNMDAP and OHNMDAP were also tested by some selected bacteria in vitro medium.