- Naphthoquinone based chemosensors for transition metal ions: Experiment and theory
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The synthesis and characterization of 2-((pyridine-2-yl)methylamino)naphthalene-1,4-dione (H-1), 2-((thiophen-2-yl)methylamino)naphthalene-1,4-dione (H-2) and 2-((pyridine/thiophen-2-yl)ethylamino) naphthalene-1,4-dione (H-3 and H-4) have been carried out. Molecular recognition abilities of these ligands toward transition metal ions in methanol, methanol-water, methanol-triethylamine or methanol-water-triethylamine mixtures, stoichiometries and association constants of H-1 and H-3 have been determined. It has been shown that H-1 and H-3 coordinate to metal ions via two nitrogen atoms and oxygen and exhibit remarkable selectivity towards Cu2+ ions in methanol or methanol-water mixtures, the complexation being accompanied by a color change from orange to intense blue. LOD (Limit of Detection) of Cu2+ with H-1, H-3 are 1.48 × 10-8 mol L-1 and 1.59 × 10-8 mol L-1 respectively. The vibrational spectra, 1H NMR chemical shifts and optical properties of H-1 to H-4 derived from density functional theory are also presented.
- Gosavi-Mirkute, Prajkta,Patil, Amit,Lande, Dipali N.,Chakravarty, Debamitra,Gejji, Shridhar P.,Satpute, Surekha,Salunke-Gawali, Sunita
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- Selectivity in changes of fluorescence emission of 1,4-naphthoquinone derivatives by manganese and cadmium ions
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Interactions of various metal ions with pyridine tethered 1,4-naphthoquinone derivatives (1-4) are studied by fluorescence spectroscopy. The fluorescence emission of 2-(pyridine-2-yl-methylamino) naphthalene-1,4-dione (1) is influenced by various metal ions and show highly selective fluorescence emission with Mn2+ ions and fluorescence ON and OFF states can be generated at different concentrations of Mn2+ ions. Sequential addition of Ni2+ and Mn2+ ions to a solution of 1 also generates ON and OFF emission states. The fluorescence responses towards the metal ions by two isomers 2-(pyridine-n-yl-methylamino)naphthalene-1,4-dione (n = 3,4) are non-specific. The 2-(pyridine-2-yl-ethylamino)naphthalene-1,4-dione (4) shows fluorescence response to various metal ions; but its fluorescence response upon interaction with cadmium ions is very unique. Three stages in emission upon increase in concentration of Cd2+ ions, namely OFF-ON-ON are observed.
- Jali, Bigyan Ranjan,Masud, Kazi,Baruah, Jubaraj B.
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- Design, synthesis, characterization and cation sensing behavior of amino-naphthoquinone receptor: Selective colorimetric sensing of Cu(II) ion in nearly aqueous solution with mimicking logic gate operation
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An amino-naphthoquione receptor (R1) has been rationally designed, synthesized and characterized using 1H and 13C NMR, LCMS and single crystal X-ray diffraction studies. The receptor exhibits an instantaneous colour change from yellow to blue selectively with Cu(II) ions in water-DMF (98:2% v/v) medium. The results of UV–Vis and fluorescence spectral studies indicates that the mechanism of sensing involves formation of a 1:1 complex between R1 and Cu(II) ion. The proposed mechanism has been confirmed through product analysis using FT-IR, UV–Vis, EPR and HRMS studies in addition to magnetic moment and elemental analysis measurements. The formed [Cu(R1)Cl2] possess a square planar geometry. The binding constant for the interaction of Cu(II) ion with the present unsubstituted quinone is found to be relatively higher than that with quinones containing electron withdrawing chlorine atom and electron releasing methyl group reported in literature. The detection limit of Cu(II) ion in aqueous solution by R1 is observed to be 8.7?nM. The detection of Cu(II) ion by R1 in aqueous solution produces remarkable changes in the electronic and fluorescence spectra, which is applied to construct logic gate at molecular level.
- Parthiban,Elango, Kuppanagounder P.
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- Synthetic enamine naphthoquinone derived from lawsone as cytotoxic agents assessed by in vitro and in silico evaluations
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We synthesized ten enamine naphthoquinones with yields ranging from 43 to 76%. These compounds were screened for their in vitro antiproliferative activities by MTT assay against four types of human cancer cell lines: HCT116, PC3, HL60 and SNB19. The naphthoquinones bearing the picolylamine (7) and quinoline (12) moieties were the most actives (IC50 2–C3 internuclear repulsion and the molecular dipole moment, relate to the biological response. Furthermore, Molecular Docking simulations indicate that the synthetic compounds have the potential to act as anticancer molecules by inhibiting topoisomerase-II and thymidylate synthase.
- Carneiro, José Walkimar M.,Costa, Pedro Mikael S.,Filho, Eclair Venturini,Fiorot, Rodolfo G.,Gomes, Anne Caroline C.,Greco, Sandro J.,Guimar?es, Celina J.,Lemos, Bárbara C.,Pessoa, Claudia,Westphal, Regina,de Oliveira, Fátima C. E.
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supporting information
(2021/11/11)
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- Synthesis, antitumor activity and docking of 2,3-(substituted)-1,4-naphthoquinone derivatives containing nitrogen, oxygen and sulfur
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Eleven 2,3-(substituted)-1,4-naphthoquinone derivatives were synthesized in yields ranging from 52-89percent. These derivatives were evaluated for their cytotoxic effects on human lungs (H460), triple-negative breast (MDA-MB-231) and ovarian (A2780) cancer cell lines. Compounds 5f and 8 showed IC50 values of 3.048 × 10-5 mol L-1 and 4.24 × 10-6 mol L-1 for H460; 5c and 8 showed IC50 values of 2.16 × 10-5 mol L-1 and 1.60 × 10-5 mol L-1 for MDA-MB-231, and 5g and 8 showed IC50 values of 2.68 × 10-6 mol L-1 and 3.89 × 10-6 mol L-1 for A2780. Additionally, we conducted a docking study with the four most active compounds and the therapeutic targets PI3K and topoisomerase II showing the pharmacophoric conformation of these compounds.
- Delarmelina, Maicon,Daltoé, Renata D.,Cerri, Murilo F.,Madeira, Klesia P.,Rangel, Leticia B. A.,Júnior, Valdemar Lacerda,Rom?o, Wanderson,Taranto, Alex G.,Greco, Sandro J.
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p. 1804 - 1816
(2015/09/22)
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- COMPOSITIONS AND METHODS FOR TREATING NEUROLOGICAL DISEASES OR INJURY
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Provided are compounds for the treatment of neurological diseases or injuries, including neurodegenerative diseases, stroke, trauma, epilepsy, acute and chronic kidney injuries, diabetes mellitus, and/or seizures. In some embodiments, derivatives of vitamin K are provided.
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Paragraph 00224
(2014/05/24)
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- Structure-activity relationship study of vitamin K derivatives yields highly potent neuroprotective agents
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Historically known for its role in blood coagulation and bone formation, vitamin K (VK) has begun to emerge as an important nutrient for brain function. While VK involvement in the brain has not been fully explored, it is well-known that oxidative stress plays a critical role in neurodegenerative diseases. It was recently reported that VK protects neurons and oligodendrocytes from oxidative injury and rescues Drosophila from mitochondrial defects associated with Parkinson's disease. In this study, we take a chemical approach to define the optimal and minimum pharmacophore responsible for the neuroprotective effects of VK. In doing so, we have developed a series of potent VK analogues with favorable drug characteristics that provide full protection at nanomolar concentrations in a well-defined model of neuronal oxidative stress. Additionally, we have characterized key cellular responses and biomarkers consistent with the compounds' ability to rescue cells from oxidative stress induced cell death.
- Josey, Benjamin J.,Inks, Elizabeth S.,Wen, Xuejun,Chou, C. James
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p. 1007 - 1022
(2013/03/28)
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