Synthesis, Characterization and Antifungal Activity of Some Metal Complexes Derived from Quinoxaloylhydrazone

New Complexes of Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II) and Tin(II) with 3-methyl-2- (pyridine-2-yl-methylene-hydrazinocarbonyl)quinoxaline-4-oxide (LHP) and 2-(2-hydroxy benzylidene- hydrazinocarbonyl)-3-methylquinoxaline-4-oxide (LHS) were prepared. The new complexes were characterized by elemental analysis, conductivity, magnetic measurements, IR and UV-Vis spectroscopic measurements. The results indicate 1:1 [M:L] chelates with the general formula [M(LHP)Cl2].nH2O where: M = Mn(II), n=4, Co(II), n=1/2, Cu(II), n=1, Hg(II), n=1, and 1:2 [M:L] in case of [M(LHS)2](OAc)2.nH2O when M = Zn(II), n= 3, Cd(II), n= 1, Hg(II), n= 1/2. The tin complex structure is suggested to be [Sn(LHP)2]Cl2.2H2O, while copper produces [Cu2(LHS)2SO4].H2O complexes. Also, the formula for mercuric complex found to be [Hg(LHS)2Cl2].2H2O. The magnetic moment measurements and electronic spectra suggest octahedral geometry for the prepared complexes. The antifungal investigation reveals that the activity was enhanced by chelation. The Cu(II) complexes has the highest inhibition zone against A. niger. But, the antifungal activity was weaker than the standard drug used.