New 14-membered octaazamacrocyclic complexes: Synthesis, spectral, antibacterial and antifungal studies
ABSTRACT A novel series of macrocyclic complexes of the type [M(C(18)H(14)N(10)S(2))X]X(2) where M=Cr(III), Fe(III) and Mn(III); X=Cl(-), NO(3)(-) and CH(3)COO(-) have been synthesized by [2+2] condensation of thiocarbohydrazide and isatin in the presence of trivalent metal salts in methanolic medium by template method. The complexes have been characterized with the help of elemental analyses, conductance measurements, magnetic measurements, electronic, NMR, IR and mass spectral studies. On the basis of these studies, a five coordinate square pyramidal geometry for all of these complexes has been proposed. These metal complexes were also tested for their in vitro antimicrobial activities against some bacterial strains viz. Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and some fungal strains Aspergillus niger, Aspergillus flavus (molds), Candida albicans, Saccharomyces cerevisiae (yeasts).
- SourceAvailable from: Franc Perdih[Show abstract] [Hide abstract]
ABSTRACT: The manganese(II) complexes with the quinolone antimicrobial agent sparfloxacin (Hsf) in the absence or presence of the nitrogen–donor heterocyclic ligands 1,10–phenanthroline (phen), 2,2'–bipyridine (bipy), 2,2'–bipyridylamine (bipyam) or pyridine (py) were synthesized and characterized with diverse physicochemical and spectroscopic techniques. The crystal structure of complex [Mn(sf)2(phen)]∙4MeOH was determined by X–ray crystallography. In the resultant complexes, the deprotonated sparfloxacinato ligands are bidentately bound to manganese(II) through the pyridone oxygen and a carboxylato oxygen. The antimicrobial activity of the complexes was tested against four different microorganisms (Escherichia coli, Xanthomonas campestris, Staphylococcus aureus and Bacillus subtilis) and was found similar or higher than free Hsf. The binding of the complexes to calf–thymus DNA (CT DNA) was monitored by UV spectroscopy and DNA viscosity measurements, which indicated intercalation as the most possible mode, and the DNA–binding strength of the complexes were calculated. The ability of the complexes to displace ethidium bromide (EB) from the EB–DNA complex was also investigated. Fluorescence emission spectroscopy was used to evaluate the interaction of the complexes with human or bovine serum albumin proteins revealing their binding with relatively high binding constant values.RSC Advances 01/2015; DOI:10.1039/C4RA11682H · 3.71 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Manganese(III) complex (1) [Mn(8-hq)3] (where 8-hq=8-hydroxyquinoline) has been synthesized and characterized by elemental, spectral (UV-vis, FT-IR) and thermal analysis. The structure of complex (1) has been determined by single crystal X-ray diffraction studies and the configuration around manganese(III) ion was elongated octahedral coordination geometry. Density functional theory calculations were performed for ligand and its complex. Binding studies of ligand and complex 1 with calf thymus DNA (CT-DNA) was investigated by absorption, fluorescence, circular dichroic (CD) spectroscopy and viscosity measurements. Absorption spectral studies revealed that ligand and complex 1 binds to DNA groove and its intrinsic binding strength has been found to be 2.57×10(4) and 2.91×10(4)M(-1). A molecular docking study confirm that the complex 1 is a minor groove binder and was stabilized through hydrogen bonding interactions. Complex 1 exhibits a good binding propensity to bovine serum albumin (BSA) protein. The in vitro cytotoxicity study of complex 1 on breast cancer cell line (MCF-7) indicate that it has the potential to act as effective anticancer drug, with IC50 values of 3.25μM. The ligand and its complex have been screened for antimicrobial activities and the complex showed better antimicrobial activity than the free ligand. Copyright © 2014 Elsevier B.V. All rights reserved.Journal of Photochemistry and Photobiology B Biology 12/2014; 142C:220-231. DOI:10.1016/j.jphotobiol.2014.12.001 · 2.80 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: A manganese(II) complex of 4-(4-methylphenyl)-3,5-bis(2-pyridyl)-4H-1,2,4-triazole (MBPT) was synthesized and characterized by X-ray crystallography. [Mn(MBPT)2(H2O)2](ClO4)2 · 4H2O is a divalent mononuclear manganese(II) complex with manganese coordinated to four nitrogens from two triazole ligands and two oxygens from two water molecules in a slightly distorted octahedral geometry. The complex and ligand were tested in vitro for their antibacterial activities. The title complex showed a wide range of bactericidal activities.Journal of Coordination Chemistry 05/2011; 64(9):1602-1607. DOI:10.1080/00958972.2011.576758 · 2.22 Impact Factor