Int J Lab Hematol
October 2024
We report the DNA-binding properties of three porphyrins with peripheral thienyl substituents (, and ). The binding capacity of each porphyrin with DNA was determined by UV-Vis and steady-state fluorescence emission spectroscopy combined with molecular docking calculations. The results suggest that the interaction of these compounds probably occurs via secondary interactions via external grooves (minor grooves) around the DNA macromolecule.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
May 2023
Due to the scarcity of spectroscopic studies on metal-coordinated naphthalimides, and aiming to investigate fundamental spectroscopic aspects, we have described here the aggregates of N-(4-pyridyl)-1,8-naphthalimide (NI-py) in solution as well as solvatochromism displayed by it and by the coordination compounds [RuO(CHCOO)(NI-py)], n = +1 or 0. Based both on theoretical calculations and luminescence spectra, we demonstrated that in aqueous media, the NI-py π-stacking is thermodynamically favored, suggesting a preferable conformation where the pyridine and naphthalene moieties of two NI-py molecules are parallel to each other, but are not co-planar within an individual molecule, due to steric hindrance. The NI-py ππ* band displayed positive solvatochromism, to which the major contribution was the Catalan's SP parameter (solvent polarizability).
View Article and Find Full Text PDFTrinuclear ruthenium complexes with orthometalated phenazines of general formula [Ru3(μ3-O)(μ2-OAc)5(L)(py)2]PF6 (L = dppn, benzo[i]dipyrido[3,2-a:2',3'-c]phenazine, 1; dppz, dipyrido[3,2-a:2',3'-c]phenazine, 2; CH3-dppz, 7-methyldipyrido[3,2-a:2',3'-c]phenazine, 3; Cl-dppz, 7-chlorodipyrido[3,2-a:2',3'-c]phenazine, 4) were investigated for their cytotoxic activity toward the B16F10 murine melanoma and the L929 non-cancer cell lines and against Trypanosoma cruzi (2-4). This study also reports a multi-technique investigation into how complexes 1-4 interact with DNA and human serum albumin, HSA. At concentrations ranging from 2 to 50 μM, all the complexes reduced B16F10 murine melanoma cell viability by over 50%.
View Article and Find Full Text PDFThis work reports a series of five-acetate triruthenium clusters [RuO(OAc)(L)(py)]PF, where L = dppn (benzo[i]dipyrido[3,2-a:2',3'-c]phenazine, 1); dppz (dipyrido[3,2-a:2',3'-c]phenazine, 2); CH-dppz (7-methyldipyrido [3,2-a:2',3'-c] phenazine, 3); Cl-dppz (7-chlorodipyrido [3,2-a:2',3'-c] phenazine, 4); and phen (1,10-phenanthroline, 5). The EPR spectra collected at 10 K displayed one isotropic signal without a hyperfine structure and with g values of ∼2.0, which showed that the five-acetate triruthenium clusters are paramagnetic, and that their electronic delocalization resembled the electronic delocalization of the parent hexa-acetate complexes.
View Article and Find Full Text PDFIt is known that aziridines and nitrogen mustards exert their biological activities, especially in chemotherapy, via DNA alkylation. The studied scaffold, 2-phenyl-1-aziridine, provides a distinct conformation compared to commonly used aziridines, and therefore, leads to a change in high-strained ring reactivity towards biological nucleophiles, such as DNA. The above series of compounds was tested in three breast cell lines: MCF-10, a healthy cell; MCF-7, a hormone responsive cancer cell; and MDA-MB-231, a triple negative breast cancer cell.
View Article and Find Full Text PDFTwo novel triruthenium clusters, [Ru(μ-O)(μ-OOCCH)(NO)L]PF (L = 4‑acetylpyridine, 1, or 4‑tert‑butylpyridine, 2) release NO. Their spectroscopic and electrochemical characterization confirmed their structure. These complexes efficiently deliver NO in solution under irradiation at λ = 377 nm and/or through chemical reduction with ascorbic acid.
View Article and Find Full Text PDFThis work reports on the trypanocidal activity of a series of symmetric triruthenium complexes combined with azanaphthalene ligands of general formula [RuO(CHCOO)(L)]PF (L=(1) quinazoline (qui), (2) 5-nitroisoquinoline (5-nitroiq), (3) 5-bromoisoquinoline (5-briq), (4) isoquinoline (iq), (5) 5-aminoisoquinoline (5-amiq), and (6) 5,6,7,8-tetrahydroisoquinoline (thiq)). All complexes within the series presented in vitro trypanocidal activity against both the trypomastigote and amastigote forms of T. cruzi.
View Article and Find Full Text PDFJ Pharm Biomed Anal
October 2017
Drug Delivery Systems (DDS) of known drugs are prominent candidates towards new and more-effective treatments of various infectious diseases as they may increase drug bioavailability, control drug delivery and target the site of action. In this sense, the encapsulation of Amphotericin B (AmB) in Nanostructured Lipid Carriers (NLCs) designed with pH-sensible phospholipids to target infectious tissues was proposed and suitable analytical methods were validated, as well as, proper nanoparticle characterization were conducted. Characterization assays by Dinamic Light Scattering (DLS) and Atomic Force Microscopy demonstrated spherical particles with nanometric size 268.
View Article and Find Full Text PDFWe report on the investigation of a new series of symmetric trinuclear ruthenium complexes combined with azanaphthalene ligands: [RuO(CHCOO)(L)]PF where L = (1) quinazoline (qui), (2) 5-nitroisoquinoline (5-nitroiq), (3) 5-bromoisoquinoline (5-briq), (4) isoquinoline (iq), (5) 5-aminoisoquinoline (5-amiq), and (6) 5,6,7,8-tetrahydroisoquinoline (thiq). The crystal structure of complex 1, [RuO(CHCOO)(qui)]PF, was determined by X-ray diffraction analysis, showing a high degree of co-planarity between the [RuO] plane and the azanaphthalene ligands. Spectroscopic (UV-visible, NMR and infra-red) and electrochemical (cyclic voltammetry and spectroelectrochemistry) data showed correlation with the pK values of the azanaphthalene ligands and this dependence was rationalized in terms of the molecular orbital of the [RuO] unit and the structure of the ligands.
View Article and Find Full Text PDFWe synthesized and characterized a series of oxo-centered carbonyl-triruthenium complexes with the general formula [RuO(CHCOO)(L)(CO)], where L = 2,6-dimethylpyrazine (dmpz) (1), isonicotinamide (adpy) (2), 4-acetylpyridine (acpy) (3), 3-methylpyridine (3-pic) (4), 4-methylpyridine (4-pic) (5), 4-tert-butylpyridine (4-tbpy) (6), 4-(dimethyl)aminopyridine (dmap) (7), or 4-aminopyridine (ampy) (8); we also investigated the photoreactivity of these complexes. Single-crystal X-ray diffraction helped to elucidate the structures of 1·HO, 7·CHCl, and 8. The unit cell of 8 is composed of four cluster units; the hydrogen bonds between the amino groups of the terminal ligand of a neighboring molecule and the oxygen atoms of CO or acetate bridging ligands hold these cluster units together.
View Article and Find Full Text PDFJ Inorg Biochem
December 2015
This work presents the synthesis and characterization of two novel binuclear ruthenium compounds of general formula [Ru2O(carb)2(py)6](PF6)2, where py=pyridine and carb are the non-steroidal anti-inflammatory drugs ibuprofen (1) and ketoprofen (2). Both complexes were characterized by ESI-MS/MS spectrometry. The fragmentation patterns, which confirm the proposed structures, are presented.
View Article and Find Full Text PDFIn vitro cytotoxicity study of the [Ru3O(CH3COO)6(4-pic)2(NO)]PF6 triruthenium nitrosyl cluster (compound 1, 4-pic=4-methylpyridine) against B16F10 melanoma cell line was evaluated in the presence and absence of visible light irradiation. The nitrosyl cluster 1 showed a significant tumoricidal activity when irradiated at λ=532 nm, reducing cell viability up to 90% at a concentration of 62.5 μM.
View Article and Find Full Text PDFNat Prod Commun
November 2011
This communication describes the in situ combination of Al(III) and Zn(II) with resveratrol, and evaluation of the antioxidant power of the novel species via DPPH* assay. The formation of the complexes in aqueous medium was verified by Job's method, using fluorescence spectroscopy. The metal/ligand stoichiometry for the Zn(II)/resveratrol complex was found to be 1:2 and, for the Al(III)/resveratrol complex two preferential species were formed with 1:1 and 3:1 stoichiometries.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
June 2008
Al-catechin/beta-cyclodextrin and Al-quercetin/beta-cyclodextrin (beta-CD) inclusion compounds were synthesized and characterized by IR, UV-vis, 1H and 13C NMR and TG and DTA analyses. Because quercetin is sparingly soluble in water, the stability constants of the Al-quercetin/beta-CD and Al-catechin/beta-CD compounds were determined by phase solubility studies. The AL-type diagrams indicated the formation of 1:1 inclusion compounds and allowed calculation of the stability constants.
View Article and Find Full Text PDFIn this work, the interaction between fisetin (3,3',4',7-tetrahydroxyflavone) (Fis) and cyclodextrins (CDs) (alpha and beta) was studied through UV-vis absorption, steady-state fluorescence, induced circular dichroism, and (1)H NMR experiments with dependence on temperature and pH. Some experimental data were compared with quantum-mechanics studies based on the SAM1 (AMPAC) semiempirical model, as well as with the B3LYP and MPW1PW91 functional models from density functional theory using the 6-311G and 3-21G basis sets. The spectroscopic measurements show that Fis does not form stable complexes with alpha-CD.
View Article and Find Full Text PDFThe synthesis of cis-[Ru(II)(cyclen)(L)(x)](n+) (cyclen = 1,4,7,10-tetraazacyclododecane and L = 2,2'-bipyridine (bpy), phenanthroline (phen) or 4-cyanopyridinium (4-NCpyH(+))) is reported. The freshly prepared complexes are stable in aprotic solvents and cyclen undergoes oxidative dehydrogenation reaction at high pH. These compounds also present solvent dependent conformational isomerization.
View Article and Find Full Text PDFTwo novel ruthenium polypyridine complexes, [Ru(bpy)(2)Cl(BPEB)](PF(6)) and ([Ru(bpy)(2)Cl](2)(BPEB))(PF(6))(2) (BPEB = trans-1,4-bis[2-(4-pyridyl)ethenyl]benzene), were synthesized and their characterization carried out by means of elemental analysis, UV-visible spectroscopy, positive ion electrospray (ESI-MS), and tandem mass (ESI-MS/MS) spectrometry, as well as by NMR spectroscopy and cyclic voltammetry. Cyclic and differential pulse voltammetry for the mononuclear complex showed three set of waves around 1.2 V (Ru(2+/3+)), -1.
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