- Highly selective light-up Al3+ sensing by a coumarin based Schiff base probe: Subsequent phosphate sensing DNA binding and live cell imaging
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A coumarin based simple fluorescent “turn-on” probe, 4-Hydroxy-3-[(2-hydroxy-5-methoxybenzylidene)-amino]-chromen-2-one (HMC), to detect metal ion based on the chelation enhanced fluorescence (CHEF), was synthesized by condensing 3-amino-4-hydroxycoumarin and 2-hydroxy-5-methoxybenzaldehyde. It was found to be highly selective and sensitive sensor for Al3+ in 90% aqueous methanol (MeOH: 0.01?M HEPES Buffer; 9:1; v/v) at pH 7.4 in fluorescence spectroscopy. Fluorescence intensity enhancement along with 10?nm blue shift was observed only in the presence of Al3+. The HMC binds Al3+ in 1:1 stoichiometry with a binding constant, Ka?=?(9.9?±?0.04)?×?103?M?1 and the detection limit was calculated to be as low as 1.62?μM. The binding mode of interaction with Al3+ and the chelate complex formation was supported with the help of a 1H NMR spectroscopy titration, ESI–MS and also by theoretical studies. Moreover, the HMC·Al3+ ensemble subsequently detected the biologically important phosphate ions and nucleotides via fluorescence quenching. The live cell imaging study indicated that HMC is highly efficient in the detection of exogenous Al3+ in living cell.
- Sheet, Sanjoy Kumar,Sen, Bhaskar,Thounaojam, Romita,Aguan, Kripamoy,Khatua, Snehadrinarayan
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- A coumarin based Schiff base probe for selective fluorescence detection of Al3?+ and its application in live cell imaging
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A new coumarin based Schiff base compound, CSB-1 has been synthesized to detect metal ion based on the chelation enhanced fluorescence (CHEF). The cation binding properties of CSB-1 was thoroughly examined in UV–vis and fluorescence spectroscopy. In fluorescence spectroscopy the compound showed high selectivity toward Al3?+ ion and the Al3?+ can be quantified in mixed aqueous buffer solution (MeOH: 0.01?M HEPES Buffer; 9:1; v/v) at pH?7.4 as well as in BSA media. The fluorescence intensity of CSB-1 was enhanced by ~?24 fold after addition of only five equivalents of Al3?+. The fluorescence titration of CSB-1 with Al3?+ in mixed aqueous buffer afforded a binding constant, Ka?=?(1.06?±?0.2)?×?104?M??1. The colour change from light yellow to colourless and the appearance of blue fluorescence, which can be observed by the naked eye, provides a real-time method for Al3?+ sensing. Further the live cell imaging study indicated that the detection of intracellular Al3?+ ions are also readily possible in living cell.
- Sen, Bhaskar,Sheet, Sanjoy Kumar,Thounaojam, Romita,Jamatia, Ramen,Pal, Amarta Kumar,Aguan, Kripamoy,Khatua, Snehadrinarayan
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- HETEROCYCLIC BIOANTIOXIDANTS 1. REACTION OF 3-NITRO-4-CHLOROCOUMARIN WITH THIOLATING AGENTS
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The reaction of 3-nitro-4-chlorocoumarin with thiolating agents in the presence of water leads to the formation of a mixture of 3-nitro-4-hydroxycoumarin, bis(3-nitro-4-coumarinyl) sulfide, and colored labile products of undetermined structure.The reaction path can be controlled by the choice of solvent, reagent ratio, and temperature regime and by the use of weakly basic additives.
- Parfenov, E. A.,Smirnov, L. D.
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- Could X-ray analysis explain for the differing antimicrobial and antioxidant activity of two 2-arylamino-3-nitro-coumarins?
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X-Ray analyses of 4-(naphthalen-1-ylamino)- 3-nitro-chromen-2-one and 3-nitro-4-phenylamino-chromen- 2-one showed that thementioned compounds crystallize in the space groups P1- (triclinic crystal system; unit cell parameters: a = 8.087(2) ?, b = 9.241(3)
- Radulovi?, Niko S.,Bogdanovi?, Goran A.,Blagojevi?, Polina D.,Deki?, Vidosav S.,Vuki?evi?, Rastko D.
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- Pseudo three-component approach to coumarin-annulated azepines: Synthesis of coumarin[3,4-: B] azepines
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A series of coumarin-annulated azepines were synthesized via acid-catalyzed condensation of 3-amino-4-hydroxycoumarin with two equivalents of substituted acetophenones in toluene with moderate to good yields. A plausible mechanism for this pseudo three-component reaction was proposed.
- Manjappa, Kiran B.,Peng, Yu-Ting,Liou, Teau-Jiuan,Yang, Ding-Yah
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- A small library of 4-(alkylamino)-3-nitrocoumarin derivatives with potent antimicrobial activity against gastrointestinal pathogens
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Abstract: Due to a confirmed antimicrobial activity of both natural and synthetic coumarin derivatives, the present study was envisaged to provide a further insight into the antimicrobial potential of coumarins through a screening of a designed library of nine 4-(alkylamino)-3-nitrocoumarins against a panel of 24 laboratory strains and resistant (isolates) bacterial and fungal pathogens. All compounds showed some degree of strain-selective activity, that was, in some cases, very pronounced, reaching the value of 0.04 nmol/ml (i.e. 12 ng/ml) for the minimal inhibitory concentration against Candida albicans. The observed activity was higher against Gram-negative strains, among which the most susceptible strain, among both ATCC strains and clinical isolates, was Salmonella enteritidis. These results point out to a high potential of these coumarins as antimicrobials for the treatment of gastrointestinal and other infections caused by highly resistant microbial strains. Finally, a multivariate statistical analysis of the herein obtained and previous results on the antimicrobial activity of related selected coumarins was performed to allow an easier structure-activity discussion.
- Radulovi, Niko S.,Stojanovi-Radi, Zorica,Stojanovi, Predrag,Stojanovi, Nikola,Deki, Vidoslav,Deki, Biljana
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- New Coumarin Derivatives as Anti-Breast and Anti-Cervical Cancer Agents Targeting VEGFR-2 and p38α MAPK
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Breast and cervical cancers are the most common gender-specific cancers affecting women worldwide. In this investigation, we highlighted the synthesis, VEGFR-2 and p38α MAPK inhibitory activity of new series of fluorinated coumarin-based derivatives featuring a variety of bioactive chemical moieties attached or fused to the coumarin nucleus at the 3 and/or 4 position. The bioactive inhibitors were further assessed for their anti-proliferative effect against human MCF-7 breast cancer and HeLa cervical cancer cell lines, respectively. Most of the tested compounds showed potent preferential inhibition effects against human VEGFR-2 and remarkable anticancer activities in the human breast cancer cell line MCF-7. Compounds 29, 24, and 2 displayed the highest inhibitory activity against VEGFR-2 (94% inhibition) and they were the most potent anticancer agents toward MCF-7 cancer cells with IC50 values of 7.90, 8.28, and 8.30 μg/mL, respectively. Compound 13 inhibited p38α MAPK phosphorylation with a significant reduction in % cell viability against HeLa cancer cells at 10 and 30 μM. Docking experiments carried out on VEGFR-2 and p38 MAPK crystallographic structures revealed that the active compounds bind to the active sites through H-bonds, arene–cation, and hydrophobic π–π interactions. QSAR analysis demonstrated considerable correlation coefficient (R2 = 0.76969) and root mean square error (RMSE = 0.10446) values. Also, the residual values between the experimental pIC50 and predicted pIC50 are very close, indicating the reliability of the established QSAR model.
- Batran, Rasha Z.,Dawood, Dina H.,El-Seginy, Samia A.,Ali, Mamdouh M.,Maher, Timothy J.,Gugnani, Kuljeet S.,Rondon-Ortiz, Alejandro N.
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- Studies on regioselectivity of nitration of coumarins with cerium(IV) ammonium nitrate: Solid-state nitration of 6-hydroxy-coumarins on montmorillonite K-10 clay support under microwave irradiation
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6-Hydroxycoumarins and their O-methyl ethers were selectively nitrated in the carbocyclic ring even in the presence of activating 4-Me group in the 2-pyrone ring with cerium(IV) ammonium nitrate (CAN) in acetic acid and acetonitrile in acceptable-to-excellent yields. Acetonitrile was found to be a better solvent for regioselective nitration than acetic acid. Use of CAN on montmorillonite K-10 clay under microwave irradiation for expeditious solvent-free regio-selective nitration has been revealed for the first time.
- Ganguly, Nemai C.,Datta, Mrityunjoy,De, Prithwiraj,Chakravarty, Romaprosad
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- Synthesis of substituted 4-(4-((3-Nitro-2-oxo-2H-chromene-4-yl)amino)phenyl)morpholine-3-one coumarin derivatives
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A series of novel 4-(4-amino phenyl) morpholine-3-one substituted coumarin derivatives have been prepared by chloramine coupling reaction and were identified. The novel synthetic route involves nucleophilic substitution reaction of 4-chloro-3-nitro-2H-chromene-2- one with 4-(4-amino phenyl)morpholine-3-one. Due to the presence of nitro group in coumarin derivatives make substitution reaction easy and convenient at low temperature. Using DMF as solvent and K2CO3 as base various substituted 4-(4-((3-nitro-2-oxo-2H-chromen- 4-yl)amino)phenyl)morpholine-3-one derivatives (YS-1 to YS-10) can be obtain in good yield and high purity. Structural characterization of all synthesized compound was done by NMR, Mass and IR spectra.
- Sanghani, Yogesh J.,Koradiya, Suresh B.,Patel, Anilkumar S.
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p. 1461 - 1464
(2019/06/11)
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- A small library of 4-(alkylamino)-3-nitrocoumarin derivatives with potent antimicrobial activity against gastrointestinal pathogens
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Due to the confirmed antimicrobial activity of both natural and synthetic coumarin derivatives, the present study was envisaged to provide further insight into the antimicrobial potential of coumarins through the screening of a designed library of nine 4-(alkylamino)-3-nitrocoumarins against a panel of 24 laboratory strains and resistant (isolates) bacterial and fungal pathogens. All compounds showed some degree of strain-selective activity that in some cases was very pronounced, reaching the value of 0.04 nmol mL-1 (i.e., 12 ng mL-1) for the minimal inhibitory concentration against Candida albicans. The observed activities were higher against Gram-negative strains, among which the most susceptible strain, among both ATCC strains and clinical isolates, was Salmonella enterica subsp. enterica serovar Enteritidis. These results indicate to a high potential of these coumarins as antimicrobials for the treatment of gastrointestinal and other infections caused by highly resistant microbial strains. Finally, a multivariate statistical analysis of the herein obtained and previous results on the antimicrobial activity of related selected coumarins was performed to allow an easier structure-activity discussion.
- Radulovi?, Niko S.,Stojanovi?-Radi?, Zorica,Stojanovi?, Predrag,Stojanovi?, Nikola,Deki?, Vidoslav,Deki?, Biljana
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p. 315 - 327
(2015/06/16)
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- Synthesis of heteroannulated 3-nitro- and 3-aminopyridines by cyclocondensation of electron-rich aminoheterocycles with 3-nitrochromone
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3-Nitrochromone reacts with electron-rich aminoheterocycles (in glacial acetic acid at reflux) and anilines (in a mixture of DMF and TMSCl at 100-140 °C) to give a variety of hetero(carbo)annulated 3-nitropyridines. The reaction, involving a formal [3+3] cyclocondensation, proceeds in high yields and appears not to be influences greatly by the nature of the 1,3-C,N-dinucleophile as seen from the thorough scope study. The synthetic utility of the products was demonstrated by their conversion into the corresponding 3-aminopyridine derivatives. An NMR study and X-ray crystallographic analysis are reported.
- Iaroshenko, Viktor O.,Mkrtchyan, Satenik,Gevorgyan, Ashot,Vilches-Herrera, Marcelo,Sevenard, Dmitri V.,Villinger, Alexander,Ghochikyan, Tariel V.,Saghiyan, Ashot,Sosnovskikh, Vyacheslav Ya.,Langer, Peter
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experimental part
p. 2532 - 2543
(2012/05/20)
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- Synthesis and antimicrobial activity of new 4-heteroarylamino coumarin derivatives containing nitrogen and sulfur as heteroatoms
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Synthesis, spectral analysis and bioactivity of new coumarin derivatives are described in this paper. Eight new coumarin derivatives were synthesized in moderate to good yields by condensation of 4-chloro-3-nitrocoumarin and the corresponding heteroarylam
- Dekic, Biljana R.,Radulovic, Niko S.,Dekic, Vidoslav S.,Vukicevic, Rastko D.,Palic, Radosav M.
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scheme or table
p. 2246 - 2256
(2010/08/04)
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- Complete assignment of the 1H and 13C NMR spectra of antimicrobial 4-arylamino- 3-nitrocoumarin derivatives
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Herein, we describe the synthesis and complete assignment of the 1H and 13C NMR chemical shifts of a series of antimicrobial 4-arylamino-3-nitrocoumarin derivatives based on a combination of 1H and 13C NMR, sup
- Dekic, Vidoslav,Radulovic, Niko,Vukicevic, Rastko,Dekic, Biljana,Skropeta, Danielle,Palic, Radosav
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experimental part
p. 896 - 902
(2011/09/14)
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- A New approach to pyrrolocoumarin derivatives by palladium-Catalyzed reactions: Expedient construction of polycyclic lamellarin scaffold
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A new and efficient protocol for straightforward synthesis of chromeno[3,4-b]pyrrol-4(3H)-one derivatives by palladium-catalyzed sequential coupling/cyclization reactions has been developed. The key strategy relies on creation of pyrrole ring through pall
- Chen, Lei,Xu, Ming-Hua
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p. 2005 - 2012
(2011/03/18)
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- Mono-nitration of Coumarins by Nitric Oxide
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A novel methodology for the efficient and selective nitration of coumarins has been developed. The reaction of coumarins containing a hydroxy group with nitric oxide in CH2Cl2 or CH3CN gave aromatic mono- and regio-specifi
- Lei, Liandi,Yang, Desuo,Liu, Zhongquan,Wu, Longmin
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p. 985 - 992
(2007/10/03)
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- Electronic properties of Ru(II) complexes bound to a bisphenolate bridge with low lying π* orbitals
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The synthesis and a detailed investigation into the electronic properties of mononuclear and dinuclear Ru(II) complexes of the ligand bis(2-hydroxyphenyl)-2,5-dihydropyrazine (H2BHD) is described. In these complexes the Ru(II) moieties are boun
- Brady, Ian,Leane, Deirdre,Hughes, Helen P.,Forster, Robert J.,Keyes, Tia E.
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p. 334 - 341
(2007/10/03)
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- 4-hydroxycoumarin derivatives. Part XI. (1) 3-alkylthio-4-hydroxycoumarins and their oxidation products
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3-Methylthio- and 3-ethylthio-4-hydroxycoumarins were synthesized. Acetylation of these compounds with acetic anhydride and pyridine yielded respective 4-acetylcoumarins, while appropriate sulfoxides and sulfones were obtained by oxidation of alkylthio substituents with H2O2. 3-Ethplthio-4-hydroxycoumarin oxidized with nitric acid yielded 3-nitro-4-hydroxycoumarin and methylated with diazomethane gave 3-ethylthio-4-methoxycoumarin and 2-methoxy-3-ethylthiochromone.
- Sulko, Jerzy
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- SPIROCYCLIC MEISENHEIMER COMPLEXES XXVII. FORMATION OF AN ANIONIC SPIROCOMPLEX OF THE MEISENHEIMER TYPE WITH 1,3-DIOXOLANE RING IN THE 3-NITROCOUMARIN SYSTEM. A NEW METHOD FOR THE PRODUCTION OF 4-ALKOXY-3-NITROCOUMARINS
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A new method is proposed for the production of 4-alkoxy-3-nitrocoumarins by the reaction of 4-chloro- and 4-methoxy-3-nitrocoumarins with alcohols in the absence of bases.It was shown that the introduction of a second nitro group at position 6 of the coumarin ring complicates the reaction, leading to the products from opening of the α-pyrone ring.In the presence of bases the 3-nitro-4-(2-hydroxyethoxy)coumarin formed during transetherification of 4-methoxy-3-nitrocoumarin gives the corresponding salts of an anionic spirocomplex of the Meisenheimer type.
- Knyazev, V. N.,Mozhaeva, T. Ya.,Lezina, V. P.,Savel'ev, V. L.,Drozd, V.N.
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p. 1517 - 1522
(2007/10/02)
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- Coumarin derivatives for the treatment of allergies
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Pharmaceutical compositions for the treatment of allergies are produced using coumarin derivatives as the active agent. Certain of these compounds and their salts are novel.
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