Physico-chemical and antibacterial studies on the coordination compounds of N-(2-carbamoylfuranyl)-C-(3'-carboxy-2'-hydroxyphenyl) thiazolidin-4-one

An equimolar mixture of 3-formylsalicylic acid and furoic acid hydrazide, refluxed in MeOH, forms the Schiff base (I). The latter upon reacting with mercaptoacetic acid in dry benzene, undergoes cyclization and forms N-(2carbamoylfuranyl)-C-(3'-carboxy-2'-hydroxyphenyl)thiazolidin-4-one, LH3 (II). A MeOH solution of II reacts with Co(II), Ni(II), Zn(II), Fe(III) and MoO2(VI) ions and forms the coordination compounds [M(LH)(MeOH)2] [where M = Co(II), Ni(II)], [Zn(LH)], [FeCl3(LH3)] and [MoO2(acac)(LH2)] (here acacH = pentane-2,4-dione). The coordination compounds were characterized on the basis of elemental analyses, molar conductance, molecular weight, spectral (IR, reflectance, NMR) studies and magnetic susceptibility measurements. All coordination compounds are non-electrolytes (M = 2.8-11.7 mho cm mol) in DMF. II behaves as a monobasic bidentate OS donor ligand in [MoO2(acac)(LH2)], neutral tridentate ONO donor ligand in [FeCl3(LH3)], and dibasic tetradentate OONO donor ligand in [M(LH)(MeOH)2] [where M = Co(II), Ni(II)] and [Zn(LH)]. All compounds are monomers in diphenyl. The absolute coordination number of Zn(II) ion is 4 and those of Co(II), Ni(II), Fe(III) and MoO2(VI) are 6. Tetrahedral structure for [Zn(LH)] and octahedral structure for the rest of the compounds are proposed. The ligand (II) and its compounds show antibacterial activities towards E. Coli (Gram Negative) and S. Aureus (Gram positive).