Synthesis, characterization, and biological activity studies of copper(II)–metal(II) binuclear complexes of dipyridylglyoxal bis(2-hydroxybenzoyl hydrazone)

Abstract

2010) Synthesis, characterization, and biological activity studies of copper(II)-metal(II) binuclear complexes of dipyridylglyoxal bis(2-hydroxybenzoyl hydrazoneA new series of copper(II) mononuclear and copper(II)-metal(II) binuclear complexes [(H 2 L)Cu] Á H 2 O, [CuLM] Á nH 2 O, and [Cu(H 2 L)M(OAc) 2 ] Á nH 2 O, n ¼ 1-2, M ¼ Co(II), Ni(II), Cu(II), or Zn(II), and L is the anion of dipyridylglyoxal bis(2-hydroxybenzoyl hydrazone), H 4 L, were synthesized and characterized. Elemental analyses, molar conductivities, and FT-IR spectra support the formulation of these complexes. IR data suggest that H 4 L is dibasic tetradentate in [(H 2 L)Cu] Á H 2 O and [Cu(H 2 L)M(OAc) 2 ] Á nH 2 O but tetrabasic hexadentate in [CuLM] Á nH 2 O (n ¼ 1-2). Thermal studies indicate that waters are of crystallization and the complexes are thermally stable to 347-402 C depending upon the nature of the complex. Magnetic moment values indicate magnetic exchange interaction between Cu(II) and M(II) centers in binuclear complexes. The electronic spectral data show that d-d transitions of CuN 2 O 2 in the mononuclear complex are blue shifted in binuclear complexes in the sequences: Cu-Cu 4 Cu-Ni 4 Cu-Co 4 Cu-Zn, suggesting that the binuclear complexes [CuLM] Á nH 2 O are more planar than the mononuclear complex. The structures of complexes were optimized through molecular mechanics applying MM þ force field coupled with molecular dynamics simulation. [(H 2 L)Cu] Á nH 2 O, [CuLM] Á nH 2 O, and the free ligand were screened for antimicrobial activities on some Gram-positive and Gramnegative bacterial species. The free ligand is inactive against all studied bacteria. The screening data showed that [CuLCu] Á H 2 O 4 [(H 2 L)Cu] Á H 2 O 4 [CuLZn] Á H 2 O 4 [CuLNi] Á 2H 2 O % [CuLCo] Á H 2 O in order of biological activity. The data are discussed in terms of their compositions and structures.

Spectral, thermal, molecular modeling and biological studies on mono- and binuclear complexes derived from oxalo bis(2,3-butanedionehydrazone)

“…[Cu(OBH) 2 Cl 2 ]·2H 2 O has higher value against Fusarium (15 mm). Comparing these data with that of ampicillin and those obtained for different hydrazone complexes showed more or less activity [29, 30]. …”

Crystal structure of 2-methoxy-N'-(3,5-dichloro-2- hydroxybenzylidene)benzohydrazide, C15H12Cl2N2O3

“…Hydrazone derivatives have been widely investigated for their biological activity [2][3][4][5]. Recently, the crystal structures of a number of hydrazone derivatives have been reported [6][7][8][9].…”

Synthesis, Characterization and Crystal Structures of Oxovanadium(V) Complexes with Benzohydrazone and 8-Hydroxyquinoline

“…Metal complexes with hydrazones have been received particular attention in biological and medicinal chemistry [1][2][3][4] . In recent years, vanadium complexes have been reported to have interesting biological activities such as normalizing the high blood glucose levels and acting as models of haloperoxidases [5][6][7][8][9] .…”