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Síntese de 1-(selenobutil)-2-fenil-4H-selenofeno[2,3-c]cromenos via reação de ciclização mediada por sais de ferro
(Universidade Federal de Santa MariaBrasilUFSMCentro de Ciências Naturais e Exatas, 2017-12-04)
This paper reports the study developed for the preparation of 1-(butylselanyl)-2-phenyl-4H-selenopheno[2,3-c]chromenes substituted by cyclization in intramolecular cascade of arylpropargyl ethers. Firstly, the study was ...
Hybridization in the Genus Baccharis : Baccharis linearis χ B. macraei
(1991)
On morphological, chemical composition and field distribution studies, the hybrid condition of Baccharis χ intermedia DC. is discussed. B. linearis (Ruiz et Pavón) Pers. and B. macraei Hook, et Arn. are the parental species. ...
Combined use of tandem mass spectrometry and computational chemistry to study 2H-chromenes from Piper aduncum
(2019-07-01)
Natural 2H-chromenes were isolated from the crude extract of Piper aduncum (Piperaceae) and analyzed by electrospray ionization tandem mass spectrometry (ESI-MS/MS) applying collision-induced dissociation. Density functional ...
Síntese regiosseletiva de cromenos e cromenonas derivados de organocalcogênio via reações de ciclização intramolecular
(Universidade Federal de Santa MariaBRQuímicaUFSMPrograma de Pós-Graduação em Química, 2012-08-30)
In the first part of this work, a series of organochalcogen propargyl aryl ethers (19 examples) was easily prepared by reaction of propargyl aryl ethers and different organochalcogen electrophilic species. In general, the ...
Secondary metabolites isolated from Piper chimonantifolium and their antifungal activity
(TAYLOR & FRANCIS LTDABINGDON, 2012)
In this study, the CH2Cl2 extract from leaves of Piper chimonantifolium was subjected to several chromatographic separation procedures to afford one chromene (gaudichaudianic acid) as a major compound as well as two ...
Biosynthetic insights into p-Hydroxybenzoic acid-Derived benzopyrans in piper gaudichaudianum
(2018-05-01)
Piper gaudichaudianum Kunth (Piperaceae) accumulates gaudichaudianic acid, a prenylated benzopyran, as its major component. Interestingly, this trypanocidal compound occurs as a racemic mixture. Herein, transcriptomic ...
Secondary metabolites isolated from Piper chimonantifolium and their antifungal activity
(Taylor & Francis Ltd, 2012-01-01)
In this study, the CH2Cl2 extract from leaves of Piper chimonantifolium was subjected to several chromatographic separation procedures to afford one chromene (gaudichaudianic acid) as a major compound as well as two ...
The effect of chalcogen substitution on the structure and spectroscopy of 4,7-dimethyl-2: H -chromen-2-one/thione analogues
(Royal Society of Chemistry, 2017-02)
4,7-Dimethyl-2H-chromen-2-one (1) and its novel sulfur analogue 4,7-dimethyl-2H-chromen-2-thione (2) were synthesized and fully characterized by spectroscopic methods and mass spectrometry. The crystal structure of compound ...