Synthesis, spectra, dioxygen affinity and antifungal activity of Ru(III) Schiff base complexes.

The reaction of ruthenium(III) complexes, [RuX(3)(EPh(3))(3)] (E=As, X=Cl or Br; E=P, X=Cl) and [RuBr(3)(PPh(3))(2)(CH(3)OH)] with bidendate Schiff base ligands derived by condensing salicylaldehyde with methylamine (Hsalmet), cyclohexylamine (Hsalchx), 2-aminopyridine (Hsalampy) have been carried out. The complexes were characterized by analytical and spectral studies (IR, electronic and EPR) and are formulated as [RuX(EPh(3))(LL')(2)] (where LL'=monobasic bidentate Schiff base ligand; E=P or As, X=Cl or Br). An octahedral geometry has been tentatively proposed for the new complexes. Dioxygen affinity of some of the Ru(III) Schiff base complexes was studied by cyclic voltammetry. The representative Schiff bases and their complexes were tested in vitro to evaluate their activity against fungi, namely, Aspergillus flavus (A. flavus) and Fusarium species.