The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform
Marc Lemaire - One of the best experts on this subject based on the ideXlab platform.
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field assessment of 4 Hydroxycoumarin as an attractant for anthropophilic anopheles spp vectors of malaria in madagascar
Scientific Reports, 2020Co-Authors: Tovo Mbolatiana Andrianjafy, Voahangy Vestalys Ramanandraibe, Elodie Toavina Andrianarijaona, Niry Hasinandrianina Ramarosandratana, Lala Harivelo Ravaomanarivo, Patrick Mavingui, Marc LemaireAbstract:Mosquito-borne diseases like malaria are a major public health problem in tropical countries, such as Madagascar. Female Anopheles mosquito vectors the human malaria parasites (Plasmodium spp.) and is important indicator in malaria surveillance activities. Among the various means of vector control in Madagascar, the use of attractants for mass trapping of target species could be an alternative to insecticides. The aim of this study is to evaluate whether 4-Hydroxycoumarin can be used as an attractant for anthropophilic Anopheles spp. vectors of malaria. For this, a field study was conducted using CDC light traps in the village of Ambohidray, Madagascar. 16 days of trapping was conducted and four replicates nights were performed for each product tested. 4-Hydroxycoumarin, octenol and two types of blend of these products were tested. The results showed that 4-Hydroxycoumarin (2 mg) have a significant attractive effect on Anopheles spp. and significant selectivity towards Anopheles gambiae s.l, and Anopheles mascarensis which are both significant malaria vectors in Madagascar. A synergy of 4-Hydroxycoumarin with octenol was found to attract these mosquito vectors. A significant decrease in vector populations was observed during this experiment. These results suggest that 4-Hydroxycoumarin could be useful for malaria surveillance and the control of vector populations.
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efficient c 3 reductive alkylation of 4 Hydroxycoumarin by dehydrogenative oxidation of benzylic alcohols through ruthenium catalysis
ChemInform, 2014Co-Authors: Adrien Montagutromans, Manon Boulven, Florence Popowycz, Marc LemaireAbstract:Only benzylic alcohols react with 4-Hydroxycoumarin in the presence of Wilkinson′s catalyst.
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efficient c 3 reductive alkylation of 4 Hydroxycoumarin by dehydrogenative oxidation of benzylic alcohols through ruthenium catalysis
New Journal of Chemistry, 2014Co-Authors: Adrien Montagutromans, Manon Boulven, Florence Popowycz, Marc LemaireAbstract:A practical route to prepare 4-Hydroxycoumarin derivatives functionalized at the C-3 position is described through a catalytic coupling reaction between 4-Hydroxycoumarin and a series of substituted benzylic alcohols. The reaction is conducted in the presence of tris(triphenylphosphine)ruthenium(II) dichloride (5 mol%), KOH (0.2 eq.) in tertamyl alcohol under microwave irradiation at 140 °C for 2 hours.
Mladen Mintas - One of the best experts on this subject based on the ideXlab platform.
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benzylidene bis 4 Hydroxycoumarin and benzopyrano coumarin derivatives synthesis 1h 13c nmr conformational and x ray crystal structure studies and in vitro antiviral activity evaluations
Molecules, 2011Co-Authors: Davorka Zavrsnik, Samija Muratovic, Damjan Makuc, Janez Plavec, Mario Cetina, Ante Nagl, Erik De Clercq, Jan Balzarini, Mladen MintasAbstract:We report on the synthesis of 4-Hydroxycoumarin dimers 1–15 bearing an aryl substituent on the central linker and fused benzopyranocoumarin derivatives 16–20 and on their in vitro broad anti-DNA and RNA virus activity evaluations. The chemical identities and structure of compounds 1–20 were deduced from their homo- and heteronuclear NMR measurements whereas the conformational properties of 5, 14 and 20 were assessed by the use of 1D difference NOE enhancements. Unequivocal proof of the stereostructure of compounds 7, 9, 16 and 18 was obtained by single crystal X-ray diffraction method. The X-ray crystal structure analysis revealed that two 4-Hydroxycoumarin moieties in the 4-trifluoromethylphenyl- and 2-nitrophenyl derivatives (compounds 7 and 9, respectively) are intramolecularly hydrogen-bonded between hydroxyl and carbonyl oxygen atoms. Consequently, the compounds 7 and 9 adopt conformations in which two 4-hydroxy-coumarin moieties are anti-disposed. Antiviral activity evaluation results indicated that the 4-bromobenzylidene derivative of bis-(4-Hydroxycoumarin) (compound 3) possesses inhibitory activity against HSV-1 (KOS), HSV-2 (G), vaccinia virus and HSV-1 TK- KOS (ACVr) at a concentration of 9–12 μM and at a minimum cytotoxic concentration (MCC) greater than 20 μM. Compounds 4–6, 8, and 20 were active against feline herpes virus (50% effective concentration, EC50 = 5–8.1 μM), that is at a 4-7-fold lower concentration than the MCC.
Veerababu Rao Kavala - One of the best experts on this subject based on the ideXlab platform.
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synthesis of c3 nitroalkylated 4 Hydroxycoumarin and hydroxyiminodihydrofuroquinolinone derivatives via the michael addition of cyclic 1 3 dicarbonyl compounds to β nitrostyrenes
ChemInform, 2011Co-Authors: Deepak Kumar Barange, Veerababu Rao KavalaAbstract:A variety of 3-substituted 4-Hydroxycoumarin derivatives is prepared in high yields from 4-Hydroxycoumarine (I) and aromatic nitroalkenes [cf.
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synthesis of c3 nitroalkylated 4 Hydroxycoumarin and hydroxyiminodihydrofuroquinolinone derivatives via the michael addition of cyclic 1 3 dicarbonyl compounds to β nitrostyrenes
Tetrahedron, 2011Co-Authors: Deepak Kumar Barange, Veerababu Rao KavalaAbstract:Abstract Herein, we describe a practical and efficient method for the C3-alkylation of 4-Hydroxycoumarin by sonication under ‘on water’ conditions and mild temperatures using various substituted β-nitrostyrenes. In addition, we report on the development of a convenient process for the regioselective synthesis of angular hydroxyiminodihydrofuroquinolinone catalyzed by base. 4-Hydroxycoumarin and 4-hydroxy-1-methylquinolin-2(1H)-one reacted smoothly with various nitroolefins to furnish C3-nitroalkylated Hydroxycoumarin derivatives (by sonication and ‘on water’ conditions) and hydroxyiminodihydrofuroquinolinone derivatives (ambient condition) as a mixture of Z (minor) and E (major) isomers, respectively. The mild reaction conditions employed, ease of isolation of the products and excellent yields constitute important features of the methodology.
Oeesook Park - One of the best experts on this subject based on the ideXlab platform.
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synthetic approaches and biological activities of 4 Hydroxycoumarin derivatives
Molecules, 2009Co-Authors: Jaechul Jung, Oeesook ParkAbstract:The main purpose of this review is to summarize recent chemical syntheses and structural modifications of 4-Hydroxycoumarin and its derivatives, of interest due to their characteristic conjugated molecular architecture and biological activities.
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a convenient one pot synthesis of 4 Hydroxycoumarin 4 hydroxythiocoumarin and 4 hydroxyquinolin 2 1h one
Synthetic Communications, 2001Co-Authors: Jaechul Jung, Youngjo Jung, Oeesook ParkAbstract:An improved one-pot synthesis of 4-Hydroxycoumarin, 4-hydroxythiocoumarin, and 4-hydroxyquinolin-2(1H)-one from 2-hydroxyacetophenone, 2-mercaptoacetophenone, and 2-aminoacetophenone, respectively, is described. The synthetic strategies involve the acylation and internal ring cyclization. This method is readily amenable to large-scale synthesis of 4-Hydroxycoumarin, 4-hydroxythiocoumarin, and 4-hydroxyquinolin-2(1H)-one derivatives in high yields.
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simple and cost effective syntheses of 4 Hydroxycoumarin
Synthetic Communications, 1999Co-Authors: Jaechul Jung, Oeesook ParkAbstract:Abstract Two simple and inexpensive methods for the preparation of 4-Hydroxycoumarin from aspirin are described, which should be readily amenable to large scale synthesis.
Davorka Zavrsnik - One of the best experts on this subject based on the ideXlab platform.
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benzylidene bis 4 Hydroxycoumarin and benzopyrano coumarin derivatives synthesis 1h 13c nmr conformational and x ray crystal structure studies and in vitro antiviral activity evaluations
Molecules, 2011Co-Authors: Davorka Zavrsnik, Samija Muratovic, Damjan Makuc, Janez Plavec, Mario Cetina, Ante Nagl, Erik De Clercq, Jan Balzarini, Mladen MintasAbstract:We report on the synthesis of 4-Hydroxycoumarin dimers 1–15 bearing an aryl substituent on the central linker and fused benzopyranocoumarin derivatives 16–20 and on their in vitro broad anti-DNA and RNA virus activity evaluations. The chemical identities and structure of compounds 1–20 were deduced from their homo- and heteronuclear NMR measurements whereas the conformational properties of 5, 14 and 20 were assessed by the use of 1D difference NOE enhancements. Unequivocal proof of the stereostructure of compounds 7, 9, 16 and 18 was obtained by single crystal X-ray diffraction method. The X-ray crystal structure analysis revealed that two 4-Hydroxycoumarin moieties in the 4-trifluoromethylphenyl- and 2-nitrophenyl derivatives (compounds 7 and 9, respectively) are intramolecularly hydrogen-bonded between hydroxyl and carbonyl oxygen atoms. Consequently, the compounds 7 and 9 adopt conformations in which two 4-hydroxy-coumarin moieties are anti-disposed. Antiviral activity evaluation results indicated that the 4-bromobenzylidene derivative of bis-(4-Hydroxycoumarin) (compound 3) possesses inhibitory activity against HSV-1 (KOS), HSV-2 (G), vaccinia virus and HSV-1 TK- KOS (ACVr) at a concentration of 9–12 μM and at a minimum cytotoxic concentration (MCC) greater than 20 μM. Compounds 4–6, 8, and 20 were active against feline herpes virus (50% effective concentration, EC50 = 5–8.1 μM), that is at a 4-7-fold lower concentration than the MCC.
