Piperazine-Bridged Homodinuclear Transition Metal Complexes

Self-assembled transition metal dithiocarbamates of pyridine-3-carboxamide: synthesis, spectral characterization, thermal and biological studies

Synthesis of self assembled transition metal dithiocarbamates of pyridine-3-carboxamide by conventional as well as in situ methodology was reported. Characterization was done with a variety of spectroscopic techniques. Anticancer and antioxidant activity of ligand and its complexes is also tested.

Synthesis, characterization, molecular docking and biological studies of self assembled transition metal dithiocarbamates of substituted pyrrole-2-carboxaldehyde

A series of self assembled 3d transition metal dithiocarbamate, M(pdtc) [where M=Mn(II), Fe(II), Co(II), Ni(II) and Cu(II)] have been synthesized and spectroscopically characterized. The bidentate dithiocarbamate ligand Na2pdtc (Disodium-1,4-phenyldiaminobis (pyrrole-1-sulfino)dithioate) was prepared by insertion reaction of carbondisulfide with Schiff base, N,N'-bis-(1H-pyrrol-2-ylmethylene)-benzene-1,4-diamine (L1) in basic medium. The simple substitution reaction between the metal halide and Na2pdtc yielded the title complexes in moderate yields. However, the in situ procedure gives high yield with the formation of single product as evident by TLC. Elemental analysis, IR, (1)H and (13)C NMR spectra, UV-vis., magnetic susceptibility and conductance measurements were done to characterize the complexes, M(pdtc). All the evidences suggest that the complexes have tetrahedral geometry excepting Cu(II) which is found to be square planar. A symmetrical bidentate coordination of the dithiocarbamato moiety has been observed in all the complexes. The conductivity data show that the complexes are non-electrolyte in nature. The anti-oxidant activity of the ligand, Na2pdtc and its transition metal complexes, M(pdtc) have been carried out using DPPH and Cu(pdtc) was found to be most effective. The anti-microbial activity of the Na2pdtc and M(pdtc) complexes have been carried out and on this basis the molecular docking study of the most effective complex, Cu(pdtc) has also been reported.

Unique Keto-Enol Tautomerism in Transition Metal Complexes of Cyanoimidodithiocarbonate

A novel potential bidentate sulfur ligand, K2[S2CNHCOCH2CN] and its complexes with first row divalent transition metal ions of the type, M(phen)L, [M = Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Pd(II), L = S2CNHCOCH2CN and phen = 1,10-phenanthroline] have been synthesised and characterised. On the basis of IR and 1H NMR an enol form is found in the case of ligand and its complexes in the solid state whereas the complexes exist predominantly in the keto form in solution. Electronic spectra and magnetic measurement data indicate that the Ni(II), Cu(II) and Pd(II) complexes have a square-planar geometry but the others have a distorted-tetrahedral structure.