ABSTRACT
The leaves of Garcinia epunctata Stapf have furnished two new phenolic glucosides, epunctosides A and B, along with 13 known secondary metabolites identified as lanceoloside A, betulinic acid, lupeol, stigmasterol, ß-sitosterol, ß-sitosterol-3-O-ß-d-glucopyranoside, stigmasterol-3-O-ß-d-glucopyranoside, luteolin-7-O-glucoside, quercitin-7-O-glucoside, amentoflavone, robustaflavone, 4'-O-methyl-amentoflavone and 4'-O-methyl-robustaflavone. All structures were established from chemical and spectroscopic evidence including 1D and 2D NMR data as well as by comparing the obtained spectroscopic data with literature. This is the first report of the presence of phenolic glucosides in the genus Garcinia.
Subject(s)
Garcinia/chemistry , Glycosides/chemistry , Phenols/chemistry , Plant Leaves/chemistry , Biflavonoids/chemistry , Glycosides/isolation & purification , Pentacyclic Triterpenes/chemistry , Phenols/isolation & purification , Secondary Metabolism/genetics , Sitosterols/chemistry , Stigmasterol/chemistry , Triterpenes/chemistry , Betulinic AcidABSTRACT
The methanol extract of the stem heartwood of Garcinia brevipedicellata has furnished three new flavonoid C-O-C dimers, brevipedicilones A (6), B (8) and C (10), along with five previously reported flavonoid dimers, viz. amentoflavone (1), 4â³'-O-methylamentoflavone (2), robustaflavone (3), 4'-O-methyl robustaflavone (4) and tetrahinokiflavone (5). The new structures, which are composed of flavanone-flavanonol or flavanonol-flavanonol sub-units, were established based on spectroscopic analysis including 1D and 2D NMR (1H-1H COSY, HSQC, HMBC, and NOESY) spectroscopy, and by comparing their spectral data with those reported for related compounds.
Subject(s)
Flavonoids/chemistry , Garcinia/chemistry , Plant Stems/chemistry , Wood/chemistry , Flavanones/chemistry , Flavonoids/isolation & purification , Magnetic Resonance Spectroscopy/methods , Methanol/chemistry , Molecular StructureABSTRACT
Six new compounds, comprising three flavonoid glycosides and their respective coumaroyl esters, have been isolated and characterized from the methanol extract of the leaves of Campylospermum calanthum, along with three known flavonoid aglycones, 7-O-methyl apigenin (1), 7-O-methyl luteolin (2), and 7-O-methyl quercetin (3). Their structures were elucidated based on chemical evidence as well as spectroscopic analysis including 1D and 2D NMR (1H-1H COSY, HSQC, HMBC, and NOESY) spectroscopy and by comparing their spectral data with those reported for related compounds.
Subject(s)
Flavonoids/isolation & purification , Glycosides/isolation & purification , Ochnaceae/chemistry , Plant Leaves/chemistry , Magnetic Resonance Spectroscopy , Mass Spectrometry , Spectrophotometry, UltravioletABSTRACT
Six isoflavonoid derivatives among which three are new have been isolated from the stem heartwood of Lophira alata. The structures were elucidated from spectroscopic and chemical evidences. Two have unusual carbon skeletons, possibly resulting from a variant of isoflavonoid biogenesis. The two compounds form the first members of a new subclass of flavonoid compounds which we call "isobiflavonoids". The presence of these isoflavonoid compounds in this plant of the Ochnaceae family has important chemotaxonomic implications since it modifies the botanic distribution of isoflavonoid compounds in non-leguminous plants.
