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While ruthenium tris(diimine) complexes have been extensively studied, this is not the case with ruthenium bis(diimine)X2complexes where X represents a pyridinyl-based ligand. The synthesis of a new complex ([2][PF6]2) bearing two ambident Schiff base ligands (HL) constituted by the assembly of phenol and pyridinyl moieties is reported. Thanks to the heteroditopic property of HL, compound [2]2+was used as an original metalloligand for the coordination of a redox-active (Mn(iii)) and redox-inactive (Zn(ii)) second metal cation affording three heterodinuclear complexes, namely, [(bpy)2RuL2Mn(acac)][PF6]2([3][PF6]2; acac = acetylacetonate), [(bpy)2RuL2Mn(OAc)][PF6]2([4][PF6]2, OAc = acetate), and [(bpy)2RuL2Zn][PF6]2([5][PF6]2). The influence of the second metal with regard to the photophysical and electrochemical properties of the ruthenium bis(diimine)X2subunit was then investigated. In the case of Ru(ii)–Mn(iii) heterodinuclear complexes, a partial quenching of the luminescence was observed as a consequence of an efficient electron transfer process from the ruthenium to the manganese. EPR and spectrophotometric analyses of the oxidized species resulting from the one-electron oxidation of compounds [3]2+and [4]2+showed the formation of a Mn(iv) species for [3]2+and an organic free radical for [4]2+. [ABSTRACT FROM AUTHOR]