Synthesis, structure and biological activity of the O,O′-diethylphosphorohydrazonothionate Schiff base and its complexes with transition metals

N'-2-Hydroxy-3-methoxy-benzalmethylene-O,O'-diethylphosphorohydrazonothionate (HL) and its six complexes (ML2) with Cu-II, Zn-II, Ni-II, Fe-II, Co-II and Mn-II have been synthesized and characterized. The crystal structure of CuL2 shows that the metal ion is tetracoordinated, bound to 2N from imine and 2O from hydroxybenzene to form a parallelogram. The effects on Stenostigma remota cells of complexes CuL2, CoL2 and MnL2 have been determined by microcalorimetry, which indicates that the compounds inhibit the metabolism of the insect cells.