RESUMO
An investigation of Agave americana and Agave barbadensis resulted in the isolation of a new homoisoflavanoid, 7-hydroxy-3-(4-methoxybenzyl)-chroman (3), together with known compounds 7-hydroxy-3-(4-methoxybenzyl)-chroman-4-one (1), 5,7-dihydroxy-3-(4-methoxybenzyl)-chroman-4-one (2), cantalasaponin-1 (4), and 2-hydroxy-butanedioic acid-1-methyl ester (5).
Assuntos
Agave , Fitoterapia , Extratos Vegetais/química , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Componentes Aéreos da PlantaRESUMO
Two new bis(monoterpenoid) indole alkaloid glucosides, bahienoside A (1) and bahienoside B (2), together with five known compounds, 5alpha-carboxystrictosidine, angustine, strictosamide, and (E)- and (Z)-vallesiachotamine, were isolated from the aerial parts of Psychotria bahiensis collected in Trinidad, West Indies. The structures of the compounds were elucidated using 1D and 2D NMR spectral methods, viz., (1)H, (13)C, (13)C DEPT, (1)H-(1)H COSY, HSQC, HMQC, HMBC, and TOCSY aided by IR, UV, and circular dichroism measurements.
Assuntos
Alcaloides Indólicos/isolamento & purificação , Monoterpenos/isolamento & purificação , Plantas Medicinais/química , Rubiaceae/química , Acetilação , Alcaloides Indólicos/química , Estrutura Molecular , Monoterpenos/química , Ressonância Magnética Nuclear Biomolecular , Estereoisomerismo , Trinidad e TobagoRESUMO
Bioassay-guided fractionation of the methanol extracts of the aerial parts of Psychotria uliginosa Sw yielded four known bioactive compounds: benz[g]isoquinoline-5,10-dione and 1-hydroxy-4,7-megastigmadien-3-one and blumenol A, which are chemically related to S-(+)-dehydrovomifoliol a known inhibitor of the germination of lettuce seeds. Evaluation of the basic components obtained from the methanol extract of the aerial parts of Psychotria bahiensis DC. yielded five bioactive indole monoterpenoid alkaloids which are known to display various levels of antiplasmodial and antitumor activity: 5 alpha-carboxystrictosidine, angustine, strictosamide and (E) and (Z)-vallesiachotamine; and the novel epimers bahienoside A and B which are currently being investigated for biological activity. The structures were determined by means of 1D and 2D NMR techniques
Assuntos
Extratos Vegetais , Plantas Medicinais , Trinidad e TobagoRESUMO
Extracts of the stems of Jatropha divaricata have yielded the two new diterpenes ent-3 beta,14 alpha-hydroxypimara-7,9(11),15-triene-12-one (3) and the rearranged pimarane ent-15(13-->8)abeo-8 beta(ethyl)pimarane (4), which appears to be a new skeletal type. The rare cleistanthane diterpenes spruceanol (1) and cleistanthol (2) were also obtained.
Assuntos
Diterpenos/química , Euphorbiaceae/química , Plantas Medicinais/química , Diterpenos/isolamento & purificação , Jamaica , Espectroscopia de Ressonância Magnética , MetilaçãoRESUMO
Squamulosone (aromadendr-1(10)-en-9-one), isolated in large quantity from the plant Hyptis verticillata Jacq. (Labiatae), was incubated with the fungus Curvularia lunata ATCC 12017 in two different growth media. Six metabolites were isolated from each medium. with five of the products being common to both fermentations. All seven metabolites are novel. The insecticidal activity of these aromadendranes was evaluated against the sweet potato weevil Cylas formicarius elegantus.
Assuntos
Ascomicetos/metabolismo , Asteraceae/microbiologia , Sesquiterpenos/metabolismo , Ascomicetos/crescimento & desenvolvimento , Asteraceae/fisiologia , Biotransformação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Sesquiterpenos/isolamento & purificação , Espectrofotometria InfravermelhoRESUMO
Extracts of the fruit of Clusia havetiodes var. stenocarpa have yielded three new prenylated benzophenone derivatives, 28,29-epoxyplukenetione A (1), 33-hydroperoxyisoplukenetione C (2), and 15,16-dihydro-16-hydroperoxyplukenetione F (3), as well as four which have been previously described, plukenetiones C, F, and G and sampsonione G.
Assuntos
Benzofenonas/química , Plantas Medicinais/química , Benzofenonas/isolamento & purificação , Frutas/química , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Prenilação de Proteína , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
The new ergostane steroid ergosta-5,24(24')-diene-3beta,4beta,22R-triol (1), a pregnane, (E)-volkendusin, characterised as the diacetate (3), cycloartanes 4-6 and protolimonoids 7-9 were obtained from the leaves and twigs of Trichilia reticulata.
Assuntos
Ergosterol/isolamento & purificação , Furanos/isolamento & purificação , Meliaceae/química , Plantas Medicinais/química , Pregnanos/isolamento & purificação , Saponinas/isolamento & purificação , Triterpenos , Fenômenos Químicos , Físico-Química , Cromatografia , Ergosterol/análogos & derivados , Ergosterol/química , Furanos/química , Espectrometria de Massas , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Caules de Planta/química , Pregnanos/química , Saponinas/química , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , EstereoisomerismoRESUMO
Four structurally novel isomeric sesquiterpenes have been isolated from the aerial parts of Capraria biflora. Caprariolides A (1), B (2), C (3), and D (4) have been determined by NMR spectroscopy experiments to be the (3S,5S,9R), (3R,5S,9R), (3R,5R,9R), and (3S,5R, 9R) isomers of 7-(furan-3'-yl)-3,9-dimethyl-1-oxaspiro[4. 5]dec-6-en-2-one, respectively. Both 1 and 2 were found to exhibit insecticidal activity against adult Cylas formicarius elegantulus, one of the most destructive insect pests of the sweet potato, Ipomoea sp.
Assuntos
Inseticidas/isolamento & purificação , Plantas Medicinais/química , Sesquiterpenos/isolamento & purificação , Inseticidas/farmacologia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Conformação Molecular , Extratos Vegetais/análise , Folhas de Planta/química , Caules de Planta/química , Sesquiterpenos/farmacologia , Índias OcidentaisRESUMO
A new sesquiterpene derivative named mochiquinone (1) was isolated from the Caribbean gorgonian coral Pseudopterogorgia rigida collected off northeastern Venezuela, along with the known compounds, alpha-curcumene, (-)-curcuphenol, (-)-curcuquinone, and (-)-curcuhydroquinone. The structure of the new compound was determined by spectroscopic analysis of its acetylated derivative and comparison with known compounds.
Assuntos
Cnidários/química , Sesquiterpenos/química , Acetilação , Animais , Região do Caribe , Cromatografia em Camada Fina , Espectroscopia de Ressonância Magnética , Sesquiterpenos/isolamento & purificação , Espectrofotometria Infravermelho , Espectrofotometria UltravioletaRESUMO
Three new monotetrahydrofuran (mono-THF) acetogenins, anmontanins A-C (1-3) were isolated from the leaves of Annona montana. Anmontanin C (3) is the first stereochemically pure acetogenin reported to have a gamma-hydroxymethyl-gamma-lactone moiety. Two known mono-THF acetogenins, murisolin and annonacin, were isolated from the seeds of the plant. The structures of compounds 1-3 were elucidated by spectral methods and chemical derivatization.
Assuntos
Furanos/isolamento & purificação , Lactonas/isolamento & purificação , Árvores/química , Furanos/química , Lactonas/química , Espectroscopia de Ressonância Magnética , Modelos Químicos , Folhas de Planta/química , Espectrometria de Massas de Bombardeamento Rápido de ÁtomosRESUMO
The structures of three new compounds isolated from Peperomia proctorii, named proctoriones A-C, have been established by spectroscopic and chemical methods as 2,3-dihydro-5, 8-dihydroxy-2-pentadecyl-4H-benzopyran-4-one (1) and enolic forms of 4-hydroxy-2-octadecanoylcyclohexane-1,3-dione (2) and 4-hydroxy-2-octadec-(11Z)-enoylcyclohexane-1,3-dione (3).
Assuntos
Cicloexanos/isolamento & purificação , Plantas/química , Cicloexanos/química , Estrutura Molecular , Análise EspectralRESUMO
A previously isolated trihydroxy-gorgosterol derivative (2), a new gorgosterol (3), and the known sterol cholestane-3beta,5alpha, 6beta-triol are reported from the Caribbean octocoral Eunicea laciniata collected off northeast Venezuela. Using high-resolution 2D NMR techniques, the total structural assignment and detailed stereochemistry of 2 is presented for the first time and the full structure of 3 advanced.
Assuntos
Colestanóis/isolamento & purificação , Colesterol/análogos & derivados , Colesterol/isolamento & purificação , Cnidários/química , Animais , Colestanóis/química , Colestanóis/farmacologia , Colesterol/química , Estrutura Molecular , Análise EspectralRESUMO
Bioassay-directed fractionation of the methanolic extract of seeds of Casimiroa edulis led to the isolation of seven constituents with cardiovascular activity, namely the new compound synephrine acetonide and the known compounds N-monomethylhistamine, N,N-dimethylhistamine, proline, N-methylproline, gamma-aminobutyric acid and casimiroedine. In anesthetized rats, both histamine derivatives produced transient hypotension mediated via H1-histaminergic receptors and in the case of N,N-dimethylhistamine, via nitric oxide release. Synephrine acetonide produced transient hypertension and tachycardia, mediated via alpha- and alpha- and beta-adrenergic receptores, respectively. The chromatographic zone containing N-methyproline, proline and gamma-aminobutyric acid elicited marked and prolonged hypotension. Finally, casimiroedine did not modify the blood pressure of anesthetized rats, but lowered it persistently in anesthetized guinea pigs. It was concluded that hypotension produced by C. edulis is due to several active components. The immediate effect can be attributed to the histamine derivatives acting on H1-receptors. More prolonged hypotension would be produced by the mixture of amino acids through an unknown mechanism, as well as by casimiroedine, possibly by activation of H3-receptors. Hypotension is partially offset by synephrine acetonide through adrenergic mechanisms.
Assuntos
Anti-Hipertensivos/farmacologia , Histamina/análogos & derivados , Medicina Tradicional , Plantas Medicinais/química , Sementes/química , Sinefrina/análogos & derivados , Animais , Anti-Hipertensivos/isolamento & purificação , Pressão Sanguínea/efeitos dos fármacos , Cobaias , Frequência Cardíaca/efeitos dos fármacos , Masculino , Metilistaminas/isolamento & purificação , Metilistaminas/farmacologia , México , Nucleosídeos/isolamento & purificação , Nucleosídeos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ratos , Ratos WistarRESUMO
Bioassay-guided fractionation of the methanol extracts of the aerial parts of Psychotria uliginosa Sw yielded four known bioactive compounds: benz[g]isoquinoline-5,10-dione and 1-hydroxy-4,7-megastigmadien-3-one and blumenol A, which are chemically related to S-(+)-dehydrovomifoliol a known inhibitor of the germination of lettuce seeds. Evaluation of the basic components obtained from the methanol extract of the aerial parts of Psychotria bahiensis DC. yielded five bioactive indole monoterpenoid alkaloids which are known to display various levels of antiplasmodial and antitumor activity: 5 alpha-carboxystrictosidine, angustine, strictosamide and (E) and (Z)-vallesiachotamine; and the novel epimers bahienoside A and B which are currently being investigated for biological activity. The structures were determined by means of 1D and 2D NMR techniques (AU)