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Kaouadji M.,Laboratoire Of Pharmacognosie
Tetrahedron Letters | Year: 2014

In addition to the methylated and prenylated flavonoids previously reported from Platanus acerifolia, the multistep chromatographic processing of the toluene extract of defatted fresh unripe buds resulted in the isolation of 8 metabolites. They corresponded to 5,7-dihydroxychromone, strobopinin [(2S)-5,7-dihydroxy-6-C-methylflavanone] as well as to six prenylated flavonols. Divided into two groups of three isomers, these C5-substituted flavonols are derived from either galangin (5,7-dihydroxyflavonol) or kaempferide (5,7-dihydroxy-4′-methoxyflavonol). Four of them, unknown in the plant kingdom and with either open or cyclized C5 chain, are discussed for the 13C NMR chemical shift variations when going from the open side C5 chain to the cyclized chain isomers. © 2014 Elsevier Ltd. All rights reserved. Source


Kaouadji M.,Laboratoire Of Pharmacognosie
Tetrahedron Letters | Year: 2015

Considered as an essential intermediary at the biogenesis crossroads of most of the Erica cinerea 1,9-diarylnonanoids, the highly anticipated and sought β-ericadione is finally isolated as a glycoside. Accompanied by the newly reported ericanone 3-O-galactoside as well as mixed s-trans and s-cis conformers of α-ericadione 3-O-galactoside, it stands itself currently only as 3-O-galactoside split into the major 5-keto-enol tautomer. Unlike all other E. cinerea 1,9-diarylnonanoid glucosides, it does not seem currently having a glucoside correspondent within this species. © 2015 Elsevier Ltd. Source


Lawson M.A.,Laboratoire Of Pharmacognosie | Kaouadji M.,Faculte des science et Techniques 123 | Chulia A.J.,Laboratoire Of Pharmacognosie
Tetrahedron Letters | Year: 2010

The lipophile extract of Lonchocarpus nicou roots afforded the new pyranochalcone 3-O-methylabyssinone A as well as the new rotenoids 7′-hydroxytephrosin, and 7′-nor-6′-oxo-2′,3′- dehydrorotenone, both compounds occurring with the known 7′- hydroxydeguelin and 7′-nor-6′-oxo-2′,3′-dehydro- 12aβ-hydroxyrotenone. Furthermore, two rotenoid epoxides previously reported as resulting from the direct oxidative conversion of rotenone and 12aβ-hydroxyrotenone, respectively, were isolated for the first time from a plant source. All the structures were established on the basis of UV, MS, and NMR data. © 2010 Elsevier Ltd. All rights reserved. Source


Moura S.,Laboratoire Of Pharmacognosie | Moura S.,University of Caxias do Sul | Thomassigny C.,University of Versailles | Ligeour C.,University of Versailles | And 4 more authors.
Green Chemistry | Year: 2011

Two polyhydroxylated piperidines have been prepared in short sequences from diacetone gluco- and allofuranose. The key step is a piezo-aza-Michael addition of diphenylmethanamine to enoates bearing a sugar moiety in the γ-position. The combination of ultra-high pressure associated to the presence of readily available sugars chiral pool led to the expected chiral amines in good yields and excellent stereoselectivities. © 2011 The Royal Society of Chemistry. Source


Mitaine-Offer A.-C.,Laboratoire Of Pharmacognosie | Penez N.,Laboratoire Of Pharmacognosie | Miyamoto T.,Kyushu University | Delaude C.,University of Liege | And 3 more authors.
Phytochemistry | Year: 2010

Four triterpene saponins, 3-O-β-d-glucopyranosylpresenegenin 28-O-β-d-apiofuranosyl-(1 → 3)-β-d-xylopyranosyl-(1 → 4)-[β-d-apiofuranosyl-(1 → 3)]-α-l-rhamnopyranosyl-(1 → 2)-{4-O-[(E)-3,4,5-trimethoxycinnamoyl]}-β-d-fucopyranosyl ester, 3-O-β-d-glucopyranosylpresenegenin 28-O-β-d-apiofuranosyl-(1 → 3)-β-d-xylopyranosyl-(1 → 4)-[β-d-apiofuranosyl-(1 → 3)]-α-l-rhamnopyranosyl-(1 → 2)-[(6-O-acetyl)-β-d-glucopyranosyl-(1 → 3)]-{4-O-[(E)-3,4,5-trimethoxycinnamoyl]}-β-d-fucopyranosyl ester, 3-O-β-d-glucopyranosylpresenegenin 28-O-β-d-apiofuranosyl-(1 → 3)-β-d-xylopyranosyl-(1 → 4)-[β-d-apiofuranosyl-(1 → 3)]-α-l-rhamnopyranosyl-(1 → 2)-[β-d-galactopyranosyl-(1 → 3)]-{4-O-[(E)-3,4,5-trimethoxycinnamoyl]}-β-d-fucopyranosyl ester, and 3-O-β-d-glucopyranosylpresenegenin 28-O-β-d-apiofuranosyl-(1 → 3)-[α-l-arabinopyranosyl-(1 → 4)]-β-d-xylopyranosyl-(1 → 4)-[β-d-apiofuranosyl-(1 → 3)]-α-l-rhamnopyranosyl-(1 → 2)-{4-O-[(E)-3,4,5-trimethoxycinnamoyl]}-β-d-fucopyranosyl ester, were isolated from the roots of Securidaca longepedunculata, together with three known compounds. Their structures were established mainly by 2D NMR techniques and mass spectrometry. © 2009 Elsevier Ltd. All rights reserved. Source

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