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Long-range correlations ((n)j (C,H) n > 3) in the HMBC spectra of 3-(4-oxo-4H-chromen-3-YL)-acrylic acid ethyl esters
(SOC BRASILEIRA QUIMICA, 2005-05)
A systematic study about the long-range correlations observed in the HMBC spectra of a series of cis and trans 3-(4-oxo-4H-chromen-3-yl)-acrylic acid ethyl esters, and 5-hydroxy derivatives, was carried out. The results ...
Hydrogen-bonded supramolecular array in the crystal structure of ethyl 7-hydroxy-2-oxo-2h-chromene-3-carboxylate monohydrate
(Sociedad Chilena de Quimica, 2011)
The crystal structure of ethyl 7-hydroxy-2-oxo-2H-chromene-3-carboxylate monohydrate (1), C12H10O5.H2O, was established by X-ray crystallographic analysis. The molecule of the title compound is essentially planar except ...
New thiourea and urea derivatives containing trifluoromethyl- and bis-triflouromethyl-4H-chromen-3-yl substituents
(Taylor & Francis Ltd, 2019-02)
Two new thiourea (1) and urea (2) derivatives, substituted with 2-trifluoromethyl-4H-chromen-3-yl moieties at defined positions, were obtained by convenient synthetic methodologies. The pure compounds were studied in solid ...
Síntese de selanil-(hetero)arenos e 3-selanil-4-amino-2H-cromen-2-onas via selenilação promovida por Selectfluor®
(Universidade Federal de Santa MariaBrasilQuímicaUFSMPrograma de Pós-Graduação em QuímicaCentro de Ciências Naturais e Exatas, 2021-07-26)
In the present work, two synthetic methodologies were developed to access organochalcogen compounds, from direct selenylation reactions using several (hetero)arenes or 4-amino-2H-chromen-2-ones and diorganyl diselenides ...
Derivados de 2H-cromen-2-onas acoplados a L-aminoácidos via reação de Ullmann empregados na síntese de 1,3,4-oxadiazóis 2,5-dissubstituídos
(Universidade Federal de Santa MariaBrasilQuímicaUFSMPrograma de Pós-Graduação em QuímicaCentro de Ciências Naturais e Exatas, 2014-02-28)
In the following work, an unprecedented series of 2,5- disubstituted 1,3,4-
oxadiazole 3 was synthesized from 2H-chromen-2-ones-L-amino acids derivatives 1,
targeting the union of 2H-chromen-2-one, L-amino acid and ...
Synthesis of coumarin derivatives as fluorescent probes for membrane and cell dynamics studies
(Elsevier, 2014)
Three coumarin-derived fluorescent probes, 3-acetyl-7-[(6-bromohexyl)oxy]-2H-chromen-2-one (FM1),
7-[(6-bromohexyl)oxy]-4-methyl-2H-chromen-2-one (FM2) and ethyl 2-{7-[(6-bromohexyl)oxy]-2-oxo-
2H-chromen-4-yl}acetate ...
Domino inverse electron demand Diels-Alder reactions of chromones with ethyl vinyl ether
(PERGAMON-ELSEVIER SCIENCE LTD, 2007-06-01)
E)-Ethyl 3-(4-oxo-4H-chromen-3-yi)acrylate (3), (E)-3-(4-oxo-4H-chromen-3-yl)-2-propenenitrile (12) and their 5-hydroxy-derivatives 11 and 13 undergo alternative, solvent dependent, domino reactions with ethyl vinyl ether. ...
Theoretical and experimental study of a novel psolaren derivate: (E)-9-(3,4 dimethylpent-2-enyloxy)-7H-furo[3,2-g]chromen-7-one
(Pergamon-Elsevier Science Ltd, 2014-04)
A new psolaren derivate, (E)-9-(3,4-dimethylpent-2-enyloxy)-7H-furo[3,2-g]chromen-7-one, has been isolated and characterized by experimental and theoretical methodologies. The solid state molecular structure has been ...