RESUMEN
Cu(II) complexes [Cu(mqt)(B)H2O]ClO4(1-3) of 2-thiol 4-methylquinoline and phenanthroline bases (B), viz 1,10-phenanthroline (phen in 1), Dipyrido[3,2-d:2',3'-f]quinoxaline (dpq in 2) and Dipyrido[3,2-a:2',3'-c]phenazine (dppz in 3) have been prepared and characterized by elemental analysis, IR, UV-Vis, magnetic moment values, EPR spectra and conductivity measurements. The spectral data reveal that all the complexes exhibit square-pyramidal geometry. The DNA-binding behaviors of the three complexes were investigated by absorption spectra, viscosity measurements and thermal denaturation studies. The DNA binding constants for complexes (1), (2) and (3) were determined to 2.2×10(3), 1.3×10(4) and 8.6×10(4)M(-1) respectively. The experimental results suggest that these complexes interact with DNA through groove-binding mode. The photo induced cleavage studies shows that the complexes possess photonuclease property against pUC19 DNA under UV-Visible irradiation via a mechanistic pathway involving formation of singlet oxygen as the reactive species. Antimicrobial photodynamic therapy was studied using photodynamic antimicrobial chemotherapy (PACT) assay against Escherichiacoli and all complexes exhibited significant reduction in bacterial growth on photoirradiation.
Asunto(s)
Antibacterianos/farmacología , Complejos de Coordinación/síntesis química , Cobre/farmacología , Fenantrolinas/farmacología , Fotoquimioterapia , Fármacos Fotosensibilizantes/síntesis química , Fármacos Fotosensibilizantes/farmacología , Oxígeno Singlete/metabolismo , Animales , Antibacterianos/síntesis química , Bovinos , Recuento de Colonia Microbiana , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , ADN/metabolismo , División del ADN/efectos de los fármacos , Electroforesis en Gel de Agar , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Desnaturalización de Ácido Nucleico , Fenantrolinas/síntesis química , ViscosidadRESUMEN
The new cobalt(III) and nickel(II) complexes of the type [M(L)2(H2O)2](n)(+) (where M = Co(III) or Ni(II) ion, n = 3 for Co and 2 for Ni, L = peptides Fmoc. Ala-val-OH (F-AVOH), Fmoc-Phe-Leu-Ome (F-PLOMe) and Z-Ala-Phe-CONH2 (Z-APCONH2)) were synthesized and structurally characterized by FTIR, (1)H NMR, elemental analysis and electronic spectral data. An octahedral geometry has been proposed for all the synthesized Co(III) and Ni(II) metal complexes. The binding property of the complexes with CT-DNA was studied by absorption spectral analysis, followed by viscosity measurement and thermal denaturation studies. Detailed analysis revealed that the metal complexes intercalates into the DNA base stack as intercalator. The photo induced cleavage studies shows that the complexes possess photonuclease property against pUC19 DNA under UV-Visible irradiation.
Asunto(s)
Cobalto/metabolismo , Complejos de Coordinación/síntesis química , Complejos de Coordinación/metabolismo , División del ADN , Níquel/metabolismo , Péptidos/síntesis química , Péptidos/metabolismo , Complejos de Coordinación/química , ADN/metabolismo , ADN Superhelicoidal/metabolismo , Electroforesis en Gel de Agar , Cinética , Desnaturalización de Ácido Nucleico , Péptidos/química , Plásmidos/metabolismo , Temperatura , ViscosidadRESUMEN
New metal complexes of the type [M(nih)(L)](PF(6))(n)·xH(2)O and [M(nih)(2)](PF(6))·xH(2)O (where M=Co(III) or Ni(II), L=1,10-phenanthroline (phen)/or 2,2' bipyridine (bpy), nih=2-hydroxy-1-naphthaldehyde isonicotinoyl hydrazone, n=2 or 1 and x=3 or 2) have been synthesized and characterized by elemental analysis, magnetic, IR and (1)H NMR spectral data. The electronic and magnetic moment 2.97-3.07 B.M. data infers octahedral geometry for all the complexes. The IR data reveals that Schiff base (nih) form coordination bond with the metal ion through azomethine-nitrogen, phenolic-oxygen and carbonyl-oxygen in a tridentate fashion. In addition, DNA-binding properties of these six metal complexes were investigated using absorption spectroscopy, viscosity measurements and thermal denaturation methods. The results indicated that the nickel(II) complex strongly bind with calf-thymus DNA with intrinsic DNA binding constant K(b) value of 4.9×10(4) M(-1) for (3), 4.2×10(4) M(-1) for (4), presumably via an intercalation mechanism compared to cobalt(III) complex with K(b) value of 4.6×10(4) M(-1) (1) and 4.1×10(4) M(-1) (2). The DNA Photoclevage experiment shows that, the complexes act as effective DNA cleavage agent.
Asunto(s)
Antiinfecciosos/química , Cobalto/química , Complejos de Coordinación/química , ADN/metabolismo , Níquel/química , Bases de Schiff/química , Animales , Antiinfecciosos/síntesis química , Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Infecciones Bacterianas/tratamiento farmacológico , Bovinos , Cobalto/farmacología , Complejos de Coordinación/síntesis química , Complejos de Coordinación/farmacología , Hongos/efectos de los fármacos , Humanos , Hidrazonas/síntesis química , Hidrazonas/química , Hidrazonas/farmacología , Micosis/tratamiento farmacológico , Naftalenos/síntesis química , Naftalenos/química , Naftalenos/farmacología , Níquel/farmacología , Fenantrolinas/síntesis química , Fenantrolinas/química , Fenantrolinas/farmacología , Bases de Schiff/síntesis química , Bases de Schiff/farmacologíaRESUMEN
The three Ni(II) complexes of fused aromatic N-containing ligands such as [Ni(bnp)(3)](PF(6))(2) (1), [Ni(phen)(2)(bnp)](PF(6))(2) (2) and [Ni(bpy)(2)(bnp)](PF(6))(2) (3) (where bnp=dibenzo(b)1,8-naphthpyridine, phen=1,10-phenanthroline and bpy=bipyridine) were synthesized and structurally characterized. Elemental analysis, magnetic and spectroscopic data suggested octahedral geometry for all the complexes. Binding of these complexes with (ds)DNA were analyzed by absorption spectra, viscosity and thermal denaturation studies. Detailed analysis revealed that the metal complexes intercalates into the DNA base stack as intercalator. The oxidative cleavage activities of the complexes were studied with supercoiled (SC)pUC19 DNA by using gel electrophoresis, and the results show that complexes have potent nuclease activity.