Syntheses, crystal structures, and antibacterial activities of two cobalt(III) complexes

Syntheses, structures, and antimicrobial activities of cobalt(III) complexes with two tetradentate Schiff-base ligands, (BA)2en = bis(benzoylacetone)ethylenediimine dianion and (acac)2en = bis(acetylacetone)ethylenediimine dianion, and two axial pyridines (py) have been investigated. These complexes were characterized by FT-IR, 1H-NMR, UV-Vis spectroscopy, and elemental analysis. The crystal structures of the complexes were determined by X-ray crystallography. Single-crystal X-ray diffraction analyses revealed that both complexes have distorted octahedral environments, Schiff-base ligand coordinates cobalt in four equatorial positions, and the two axial positions are occupied by pyridines. The pyridines and Schiff-base ligands are involved in N–H···O hydrogen bonds with perchlorate. Biological activities of the ligands and metal complexes have been studied on Staphylococcus aureus, Escherichia coli, and Bacillus subtilis by the well diffusion method. The activity data show the metal complexes to be more potent than the parent ligand against two bacterial species.

[1]  A. Kulkarni,et al.  DNA cleavage, antimicrobial, anti-inflammatory anthelmintic activities, and spectroscopic studies of Co(II), Ni(II), and Cu(II) complexes of biologically potential coumarin Schiff bases , 2011 .

[2]  N. Raman,et al.  Synthesis, characterization, and DNA damaging of bivalent metal complexes incorporating tetradentate dinitrogen–dioxygen ligand as potential biocidal agents , 2011 .

[3]  M. Zulfequar,et al.  Metal-containing polyurethanes from tetradentate Schiff bases: synthesis, characterization, and biocidal activities , 2011 .

[4]  A. Kulkarni,et al.  Synthesis, characterization, in vitro antimicrobial and DNA cleavage studies of Co(II), Ni(II) and Cu(II) complexes with ONOO donor coumarin Schiff bases , 2011 .

[5]  G. A. Kolawole,et al.  Synthesis, characterization, antibacterial, and thermal studies of unsymmetrical Schiff-base complexes of cobalt(II) , 2010 .

[6]  M. Kubicki,et al.  {2,2′-[1,1′-(Ethane-1,2-diyldinitrilo)diethylidyne]diphenolato}bis(pyrrolidine)cobalt(III) perchlorate p-xylene hemisolvate , 2010, Acta crystallographica. Section E, Structure reports online.

[7]  Wen-hui Li,et al.  Syntheses, crystal structures and antibacterial activities of azido-bridged cobalt(III) complexes with Schiff bases , 2010 .

[8]  P. Zavalij,et al.  Use of acid-base and redox chemistry to synthesize cobalt(III) and iron(III) complexes of a partially deprotonated triprotic imidazole-containing Schiff base ligand: Hydrogen bound 1D linear homochiral and zig-zag heterochiral supramolecular complexes , 2010 .

[9]  M. Ferraro,et al.  Antimicrobial susceptibility testing: a review of general principles and contemporary practices. , 2009, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[10]  Anthony L. Spek,et al.  Structure validation in chemical crystallography , 2009, Acta crystallographica. Section D, Biological crystallography.

[11]  R. Gupta,et al.  Synthesis, characterization and antibacterial activity of cobalt(III) complexes with pyridine-amide ligands. , 2008, European journal of medicinal chemistry.

[12]  G. Sheldrick A short history of SHELX. , 2008, Acta crystallographica. Section A, Foundations of crystallography.

[13]  M. Amirnasr,et al.  Co(III) complexes of Me-salpn and Me-salbn and the ring size effect on the coordination modes and electrochemical properties : The crystal structures of trans-[CoIII(Me -salpn ) (py )2 ]PF6 and cis-α-[CoIII(Me -salbn)(4 -Mepy )2]BPh4· 4-Mepy , 2007 .

[14]  Yong-mei Wang,et al.  Synthesis, structure and biological activity of cobalt(II) and copper(II) complexes of valine-derived schiff bases. , 2006, Journal of inorganic biochemistry.

[15]  M. Amirnasr,et al.  Synthesis, characterization, and single crystal X-ray structures of [CoIII(acacen)(thioacetamide)2]ClO4 and [CoIII((BA)2en)(thioacetamide)2]PF6 - Solvatochromic properties of [CoIII(acacen)(thioacetamide)2]ClO4 , 2005 .

[16]  T. Katsuki,et al.  Unique asymmetric catalysis of cis-beta metal complexes of salen and its related Schiff-base ligands. , 2004, Chemical Society reviews.

[17]  Yu-Ling Zhang,et al.  Synthesis and characterization of axial coordination cobalt(III) complexes containing chiral Salen ligands , 2003 .

[18]  M. Amirnasr,et al.  Synthesis, structure, and electrochemistry of cobalt(III) complexes with bis(benzoylacetone)ethylenediimine Schiff base , 2002 .

[19]  M. Amirnasr,et al.  Synthesis and spectroscopic characterization of [CoIII(salophen)(amine)2]ClO4 (amine=morpholine, pyrrolidine, and piperidine) complexes. The crystal structures of [CoIII(salophen)(morpholine)2]ClO4 and [CoIII(salophen)(pyrrolidine)2]ClO4 , 2001 .

[20]  P. Viswanathamurthi,et al.  Ruthenium(II) complexes containing bidentate Schiff bases and their antifungal activity , 2001 .

[21]  M. Ferraro Performance standards for antimicrobial susceptibility testing , 2001 .

[22]  Shoichiro Yamada,et al.  Advancement in stereochemical aspects of Schiff base metal complexes , 1999 .

[23]  N. Henson,et al.  Density Functional Theory Studies of the Binding of Molecular Oxygen with Schiff's Base Complexes of Cobalt† , 1999 .

[24]  L. Marzilli,et al.  Strong Trans Influence Methoxymethyl Ligand in B(12) Cobaloxime and Imine/Oxime Model Complexes: Structural, Spectroscopic, and Molecular Mechanics Investigations. , 1998, Inorganic chemistry.

[25]  M. Amirnasr,et al.  Synthesis and Characterization... , 1997 .

[26]  M. M. Aly RECENT DEVELOPMENTS IN THE METALLOSUPRAMOLECULAR AND MOLECULAR STRUCTURES OF THE COBALT, IRON AND VANADIUM COMPLEXES OF THE DIANIONIC TETRADENTATE SCHIFF BASE LIGANDS OF SALICYLIDINEIMINE AND ACETYLACETONEIMINE , 1998 .

[27]  R. Zoellner,et al.  Activation of Dioxygen by Cobalt Group Metal Complexes , 1997 .

[28]  G. Estiu,et al.  Quantum Chemical Calculations of the Structures and Electronic Properties of N,N'- Bis(3,5-dibromosalicylidene)-1,2-diaminobenzene and Its Cobalt(II) Complex. Origin of the Redox Activity of the Cobalt Complex. , 1996, Inorganic chemistry.

[29]  T. Mukaiyama,et al.  Enantioselective Reduction of Ketones with Sodium Borohydride, Catalyzed by Optically Active (β‐Oxoaldiminato)cobalt(II) Complexes , 1995 .

[30]  B. Speiser,et al.  Complexation of [N,N′‐Bis(salicylidene)‐ethylenediiminato]cobalt(III)+ by Anilines in Dimethylformamide , 1995 .

[31]  R. Blessing,et al.  An empirical correction for absorption anisotropy. , 1995, Acta crystallographica. Section A, Foundations of crystallography.

[32]  E. Jacobsen,et al.  Electronic tuning of asymmetric catalysts , 1991 .

[33]  K. Wieghardt,et al.  Syntheses, electrochemistry, and spectroscopic and magnetic properties of new mononuclear and binuclear complexes of vanadium(III), -(IV, and -(V) containing the tridentate macrocycle 1,4,7-trimethyl-1,4,7-triazacyclononane (L). Crystal structures of [L2V2(acac)2(.mu.-O)]I2.2H2O, [L2V2O4(.mu.-O)].14 , 1990 .

[34]  Emanuel Goldman,et al.  Practical Handbook of Microbiology , 1989 .

[35]  M. Summers,et al.  Organocobalt B12 models: axial ligand effects on the structural and coordination chemistry of cobaloximes , 1985 .

[36]  W. C. Wolsey Perchlorate salts, their uses and alternatives , 1973 .

[37]  A. Bauer,et al.  Antibiotic susceptibility testing by a standardized single disk method. , 1966, American journal of clinical pathology.

[38]  A. Martell,et al.  Inner Complex Chelates. I. Analogs of Bisacetylacetoneethylenediimine and its Metal Chelates1,2 , 1955 .