124 resultados para stigmasterol
Resumo:
The phytochemical investigation of ethanolic extracts from leaves, branches and stems of D. bipinnatum afforded the steroids β-sitosterol, stigmasterol, campesterol, sitostenone and sitosterol-3-O-β-D-glycopyranoside, along with two cycloartane triterpenes: cycloeucalenol and 24-methylenecycloartenol. The antimicrobial activity of the extracts was evaluated against Staphylococcus aureus (ATCC 25923), Escherichia coli (ATCC 25922), Bacillus subtilis (ATCC 6623), Pseudomonas aeruginosa (ATCC 15442), Micrococcus luteus (ATCC 9341) and Candida albicans (ATCC 10231). The extracts of the leaves and branches showed moderate activity against Candida albicans. The extract of the branches was active against Micrococcus luteus. This is the first report on the phytochemical study of D. bipinnatum.
Resumo:
The genus Rauia, that is poorly chemically studied, belongs to the Rutaceae family. This family has been known to contain a large variety of secondary metabolites. Our phytochemical investigation of the stem and leaves of Rauia resinosa has led to the identification of the structurally related coumarins: murralongin (1), murrangatin (2), munomicrolin (3), murrangatin diacetate (4), umbelliferone (5), rauianin (6) and one novel coumarin: 3-ethylrauianin (7); the alkaloids: N-methyl-4-methoxy-2-quinolone (8), mirtopsine (9), dictamine (10), γ-fagarine (11), skimmianine (12), Z-dimethylrhoifolinate (13), zantodioline (14), zantobungeanine (15), veprissine (16), one novel alkaloid 7-hydroxy-8-methoxy-N-methylflindersine (17) and 8-hydroxy-N-methylflindersine (18) that is described as a natural product for the first time, and a mixture of steroids: as sitosterol and stigmasterol.
Resumo:
Chemical investigation of Hyptidendron canum stems resulted in the isolation of betulinic, ursolic and euscaphic acids. From the leaves were isolated 3β-O-β-galactopiranosilsitosterol, ursolic aldehyde, and mixtures of maslinic acid and 2α-hydroxyursolic acid, α and β-amyrin, uvaol and erythrodiol, sitosterol and stigmasterol, spathulenol and globulol. Hexane and chloroform leave fractions as well as ursolic and betulinic acids showed antifungal activities against the yeast form of Paracoccidioides brasiliensis.
Resumo:
The phytochemical investigation of L. macrophylla Benth led to the isolation of a new flavanol named licanol: (-)-4'-O-methyl-epigallocatechin-3'-O-α-L-rhamnoside, along with nine known compounds, identified as: (-)-4'-O-methyl-epigallocatechin, pheophytin A, 13²-hydroxy-(13²-S)-pheophytin A, pheophytin B, sitosterol, stigmasterol, sitosterol-β-O-glucoside, betulinic alcohol and oleanolic acid. The structures were established based on IR, HR-ESI-MS, and NMR spectrometric data analysis with the aid of 2D techniques. The methanolic extracts of leaves and stem bark as well as the compounds licanol, 13²-hidroxi-(13²-S)-feofitina A, and betulinic alcohol demonstrated antimicrobial activity against several bacterial strains.
Resumo:
A new salicylic acid derivative, pentacosanyl salicylate, was isolated from the leaves of the plant toxic to cattle, Riedeliella graciliflora, in addition to a digalactosyldiacylglycerol (DGDG), 1,2-di-O-α-linolenoyl-3-O-α-D-galactopyranosyl-(1→6)-β-D-galactopyranosyl-glycerol, kaempferol-3-O-β-D-glucopyranoside, kaempferol-3-O-α-L-rhamnopyranoside, quercetin-3-O-α-L-rhamnopyranoside, rutin, (+)-catechin and the dimer (+)-catechin-(4β-8)-catechin, glutinol, squalene, β-sitosterol, stigmasterol, phytol, β-carotene, α-tocopherol and ficaprenol-12. Their structures were determined using spectral techniques (MS, IR, and NMR-1D and 2D) and based on literature data.
Resumo:
Phytochemical investigation of the hexane extract from the stem of Xylopia laevigata led to the isolation of the ent-kaurane diterpenoids, ent-kaur-16-en-19-oic acid, 4-epi-kaurenic acid, ent-16β-hydroxy-17-acetoxy-kauran-19-al, ent-3β-hydroxy-kaur-16-en-19-oic acid, and ent-16β,17-dihydroxy-kauran-19-oic acid, as well as spathulenol and a mixture of β-sitosterol, stigmasterol and campesterol. The identification of the compounds was performed on the basis of spectrometric methods including GC-MS, IR, and 1D and 2D NMR. Potent larvicidal activity against Aedes aegypti larvae with LC50 of 62.7 µg mL-1 was found for ent-3β-hydroxy-kaur-16-en-19-oic acid. This compound also showed significant antifungal activity against Candida glabrata and Candida dubliniensis with MIC values of 62.5 µg mL-1.
Resumo:
This the first phytochemical investigation of Mimosa artemisiana (Leguminosae-Mimosoideae) describing the isolation and identification of quercitrin, myricitrin, 3,5,4´-trihydroxi-6,7-dimethoxyflavone (6,7-dimethylkaepferol), flavolignans, 3-O-β-D-glucopyranosil sitosterol, lupeol, sitostenone, stigmastenone, campestenone, sitosterol, stigmasterol, campesterol, methyl indole-3-carboxilate and indole-3-carboxaldehyde in the extracts from the leaves and wood of this plant. This is the first registry of 6,7-dimethoxy,4'-hydroxy-flavona and the flavonolignans in this genera. The isolation of all metabolites was made by chromatographic methods and the structures were established on the basis of IR, MS, ¹H and 13C NMR spectra analysis, comparison with literature data and GC-MS of mixtures analysis.
Resumo:
A new triterpene, 1-epi-castanopsol, besides eleven known compounds: sitosterol, stigmasterol, campesterol, lupeol, lupenone, simirane B, syringaresinol, scopoletin, isofraxidin, 6,7,8-trimethoxycoumarin and harman, were isolated from the wood of Simira glaziovii. The structures of the known compounds were defined by 1D, 2D ¹H, 13C NMR spectra data analyses and comparison with literature data. The detailed spectral data analyses allowed the definition of the structure of the new 1-epi isomer of castanopsol and performance of ¹H and 13C NMR chemical shift assignments.
Resumo:
Phytochemical investigation of Aeschynomene fluminensis leaves and branches led to isolation of the flavonoid glycosides kaempferol 3,7-di-O-α-L-rhamnopyranoside, kaempferol 7-O-α-L-rhamnopyranoside, kaempferol 3-O-apiofuranosil-7-O- rhamnopyranoside, quercitin 3-O-α-L-rhamnopyranoside, quercitin 3-O-arabinofuranoside, 8-β-D-glucopyranosyl 4',5,7-trihydroxyflavanone, the isoflavonoid 4',7-di-hydroxy-isoflavone, the dimer epicatechin-(2β→7, 4β→8)- epicatechin, the polyol 3-O-methyl-chiro-inositol and two steroids in sitosterol and stigmasterol mixture. These compounds were identified by NMR ¹H and 13C and compared with literature data. Anti-inflammatory activity of the crude methanolic extract and its fractions was evaluated.
Resumo:
Essential oil from the leaves of Mansoa difficilis was analyzed by GC/MS. Oct-1-en-3-ol (49.65%) was the major compound, but diallyl di- and trisulfide were also present (0.85 and 0.37%, respectively), justifying the garlic-like odor of the crushed leaves. The hexane and methanol extracts of the leaves and stems afforded as main constituents a mixture of linear hydrocarbons, spinasterol, stigmasterol, ursolic and oleanolic acids, two apigenin derivatives and verbascoside. The hexane and methanol extracts of leaves were tested for antimicrobial activity against ten microorganisms. The hexane extract was active against both Psedomonas aeruginosa and Staphylococcus aureus.
Resumo:
The chemical investigation of hexane and ethanol extracts from the aerial parts of Vernonia scorpioides resulted in the isolation and characterization of a new polyacetylene lactone, rel-4-dihydro-4β-hydroxy-5a-octa-2,4,6-triynyl-furan-2-(5H)-one, along with the new ethyl 3,4-dihydroxy-6,8,10-triynyl-dodecanoate, and seven known compounds: taraxasteryl acetate, lupeyl acetate, lupeol, lupenone, β-sitosterol, stigmasterol and luteolin. The structure of all compounds was determined by spectrometric techniques (HR-ESI-MS, ¹H and 13C NMR and IV) and comparison with published spectral data.
Resumo:
The chemical investigation of the stems and branches of Macroptilium lathyroides led to the isolation of a mixture of β-sitosterol and stigmasterol. The extracts from the roots allowed the isolation of lasiodiplodin, a mixture of stigmast-4-en-6β-ol-3-one and stigmast-4,22-dien-6β-ol-3-one, de-O-methyllasiodiplodin, genistein and lupinalbin A. The structures of the isolated compounds were assigned on the basis of their NMR data, including comparison of their spectral data with values described in the literature. The antibacterial activity of crude extracts from stems, branches and roots was evaluated. This is the first report involving the chemical investigation of this species.
Resumo:
In addition to β-sitosterol, stigmasterol, phaeophitin A, luteolin, kaempferol, quercetin, (+)-catechin, quercetin-3-O-α-L-rhamnopyranoside, rutin, and p-hydroxy-benzoic acid, six known sesquiterpenes, namely (rel)-2β,6β-epoxy-5β-hydroxy-isodaucane, oplopanone, 1β,6α-dihydroxy-4(15)-eudesmene, caryophyllene oxide, α-cadinol, and spathulenol, were isolated from the leaves of Pterodon pubescens (Leguminosae) growing in the Cerrado of Mato Grosso do Sul, Brazil. The (rel)-2β,6β-epoxy-5β-hydroxy-isodaucane corresponds to the correct structure of homalomenol D. The sesquiterpene oplopanone, which bears a modified cadinane skeleton, is being reported for the first time in this genus. The structures of the compounds were determined on the basis of spectral data (MS, IR, and NMR-1D and 2D) and subsequent comparison with data reported in the literature.
Resumo:
Turnera subulata Sm., known as "Chanana" or "flor-do-Guarujá" in Brazilian folklore, is a plant species belonging to the subfamily Turneroideae of family Passifloraceae, which is used for various medicinal purposes in Brazil. The phytochemical study conducted here led to the isolation and identification of ten compounds present in T. subulata: two mixtures of steroids, sitosterol and stigmasterol (nonglycosylated and glycosylated); a mixture of flavonoids, 5,7,4′-trihidroxiflavona-8-C-α-glucopyranoside and 5,7,3′,4′-tetrahidroxiflavona-8-C-α-glucopyranosidel; and four phaeophytins, phaeophytin purpurin-18-phytyl ester, a rare natural product, phaeophytin a , 13²-hydroxy-(13²-S)-phaeophytin a , and phaeophytin b Phaeophytin b exhibited electrochemical activity similar to that of phthalocyanines.
Resumo:
The phytochemical investigation of Sabicea brasiliensis roots led to the isolation of 5-O-caffeoylquinic acid, 3,5- and 4,5-O-dicaffeoylquinics acids, scopoletin, ursolic acid, a mixture of β-sitosterol, stigmasterol and campesterol, daucosterol and saccharose. The structures of the isolated compounds were assigned on the basis of one- and two-dimensional NMR spectroscopic methods and by comparison with literature data. The anti-inflammatory and antioxidant activities of the crude methanolic extract and its fractions were analyzed.