title: Electrochemical, catalytic and antimicrobial activity of N-functionalized tetraazamacrocyclic binuclear nickel(II) complexes.
abstract: The five binuclear nickel(II) complexes have been synthesized by the Schiff base condensation of 1,8-[bis(3-formyl-2-hydroxy-5-methyl)benzyl]-l,4,8,11-tetraazacyclo-tetradecane (PC) with appropriate aliphatic diamines and nickel(II) perchlorate. All the five complexes were characterized by elemental and spectral analysis. The electronic spectra of the complexes show three d-d transition in the range of 550-1055 nm due to 3A2g→3T2g(F), 3A2g→3T1g(F) and 3A2g→3T1g(P). These spin allowed electronic transitions are characteristic of an octahedral Ni2+ center. Electrochemical studies of the complexes show two irreversible one electron reduction waves at cathodic region. The reduction potential of the complexes shifts towards anodically upon increasing the chain length of the macrocyclic ring. All the nickel(II) complexes show two irreversible one electron oxidation waves at anodic region. The oxidation potential of the complexes shift towards anodically upon increasing the chain length of the macrocyclic ring. The catalytic activities of the complexes were observed to be increase with increase the macrocyclic ring size. The observed rate constant values for the catalytic hydrolysis of 4-nitrophenyl phosphate are in the range of 5.85×10(-3) to 9.14×10(-3) min(-1). All the complexes were screened for antimicrobial activity.
authors.affiliation: Department of Inorganic Chemistry, School of Chemical Sciences, University of Madras, Guindy Campus, Chennai 600 025, India.
authors.forename: R
authors.initials: R
authors.lastname: Prabu
authors.forename: A
authors.initials: A
authors.lastname: Vijayaraj
authors.forename: R
authors.initials: R
authors.lastname: Suresh
authors.forename: R
authors.initials: R
authors.lastname: Shenbhagaraman
authors.forename: V
authors.initials: V
authors.lastname: Kaviyarasan
authors.forename: V
authors.initials: V
authors.lastname: Narayanan
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry / Q000494:pharmacology*; D000935:Antifungal Agents / Q000737:chemistry / Q000494:pharmacology; D001372:Aza Compounds / Q000737:chemistry / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects; D002384:Catalysis / Q000187:drug effects; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D004583:Electrons; D005658:Fungi / Q000187:drug effects; D006868:Hydrolysis / Q000187:drug effects; D007700:Kinetics; D047028:Macrocyclic Compounds / Q000737:chemistry / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D009532:Nickel; D009596:Nitrophenols / Q000737:chemistry; D009943:Organophosphorus Compounds / Q000737:chemistry; D010084:Oxidation-Reduction / Q000187:drug effects
chemical_list: D000890:Anti-Infective Agents; D000935:Antifungal Agents; D001372:Aza Compounds; D047028:Macrocyclic Compounds; D009596:Nitrophenols; D009943:Organophosphorus Compounds; C008644:nitrophenylphosphate; D009532:Nickel