RESUMO
The structural diversity of the metabolic pool of Pelargonium reniforme was extended by the characterization of the 1C4-glucose based ellagitannin pelargoniin E, gallic acid n-butyl ester, (-)-4,4',9'-trihydroxy-3',5'-dimethoxy-2,7'-cyclolignan 9-O-beta-glucopyranoside and reniformin, a diterpene ester comprised of a diterpene acid with an uncommon -(CH2)(2)- bridging element linked to 2-(4-hydroxyphenyl)ethansulfonic acid. These metabolites were associated with the known (alpha,beta)-3,4-di-O-galloyl-glucopyranoside, 4,6-dihydroxy-2beta-glucopyranosyloxyacetophenone, 1-O-galloylglycerol, 6'-O-galloylsalidroside and (+)-isolariciresinol-9'-O-beta-glucopyranoside. All structures were established on the basis of spectroscopic methods.
Assuntos
Diterpenos/química , Ésteres/química , Ácido Gálico/análogos & derivados , Ácido Gálico/química , Taninos Hidrolisáveis/química , Pelargonium/química , Isótopos de Carbono , Diterpenos/isolamento & purificação , Ésteres/isolamento & purificação , Ácido Gálico/isolamento & purificação , Taninos Hidrolisáveis/isolamento & purificação , Espectroscopia de Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/normas , Conformação Molecular , Pelargonium/metabolismo , Padrões de Referência , EstereoisomerismoRESUMO
A new oleanane-type saponin lactone was isolated from the ethanolic extract of the aerial parts of Astragalus corniculatus Bieb. The structure of the saponin was elucidated as 19-hydroxyolean-12-ene-28, 21beta-olide 3beta-D-xylopyranoside (1) by chemical and spectral methods.
Assuntos
Fabaceae , Fitoterapia , Extratos Vegetais/química , Humanos , Lactonas/química , Componentes Aéreos da Planta , Saponinas/químicaRESUMO
From the stem bark of Newbouldia laevis three phenylethanoid glycosides, designated as newbouldioside A-C, were isolated together with a sodium salt of analogue B and the known compounds, verbascoside, 5-hydroxydehydro-iso-alpha-lapachone, 3,8-dihydroxydehydro-iso-alpha-lapachone, apigenin and luteolin. The structures of the phenylethanoid glycosides were elucidated by spectroscopic methods as beta-(3,4-dihydroxyphenyl)ethyl 5-O-syringoyl-beta-D-apiofuranosyloxy-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->3)]-beta-D-glucopyranoside, ss-(3,4-dihydroxyphenyl)ethyl 5-O-syringoyl-beta-D-apiofuranosyloxy-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->3)]-6-O-E-feruloyl-beta-D-glucopyranoside, and beta-(3,4-dihydroxyphenyl)ethyl 3-O-E-feruloyl-beta-D-apiofuranosyloxy-(1-->2)-O-alpha-L-rhamnopyranosyl-(1-->2)-6-O-E-sinapoyl-beta-D-glucopyranoside, respectively.
Assuntos
Bignoniaceae/química , Glicosídeos/química , Casca de Planta/química , Glicosídeos/isolamento & purificação , Estrutura MolecularRESUMO
The occurrence and distribution of tropane and biogenetically related pyrrolidine alkaloids in 18 Merremia species of paleo-, neo-, and pantropical occurrence have been studied. The extensive GC-MS study included members of almost all sections of the genus and has been carried out with epigeal vegetative parts as well as with roots. It comprises altogether 74 tropanes and 13 pyrrolidines including nicotine. Along with datumetine known already from a solanaceous species, the study led to the isolation (from M. dissecta and M. guerichii, respectively) and structure elucidation (spectral data) of four novel 3alpha-acyloxytropanes, merresectines A-D: 3alpha-(4-methoxybenzoyloxy)nortropane (A), 3alpha-kurameroyloxytropane (B), 3alpha-nervogenoyloxytropane (C), 3alpha-[4-(beta-D-glucopyranosyloxy)-3-methoxy-5-(3-methyl-2-butenyl)benzoyloxy]tropane (beta-d-glucoside of D). Moreover, the novel 3alpha,6beta-di-(4-methoxybenzoyloxy)tropane (merredissine) has been isolated from M. dissecta and structurally elucidated. In addition the structures of datumetine and merresectine A could be confirmed by synthesis. Spectral data for two known 3alpha-acyloxytropanes (merresectine E beta-D-glucoside, 4'-dihydroconsabatine) and one known 3beta-acyloxytropane (concneorine) are documented for the first time. The structures of three further merresectines (F-H) have been determined by mass spectrometry. Furthermore, the linkage (2',3- and 2',4-, respectively) of two position isomer N-methylpyrrolidinylhygrines was proven by synthesis. The results of the study contribute to the solution of infrageneric taxonomic problems. Whereas all species yield pyrrolidine alkaloids without suitably differentiating results the diverging occurrence of tropane alkaloids leads to three groups of sections: (1) taxa free of tropanes, (2) taxa with simple tropanes, and (3) taxa with merresectines in addition to simple tropanes.
Assuntos
Convolvulaceae/química , Convolvulaceae/classificação , Pirrolidinas/isolamento & purificação , Tropanos/isolamento & purificação , Alcaloides/classificação , Alcaloides/isolamento & purificação , Classificação , Cromatografia Gasosa-Espectrometria de Massas , Estrutura Molecular , Extratos Vegetais/isolamento & purificação , Raízes de Plantas/química , Pirrolidinas/classificação , Tropanos/classificaçãoRESUMO
In search for bioactive compounds from Sabal species, sablacaurin A [25-ethyl,23-methyl-19-nor-24-methylene-3,4-seco-4(28)-lanosten-10,3-olide] and sablacaurin B [24-ethyl,24-methyl-19-nor-3,4-seco-4(28),25(26)-lanostadiene-10,3-olide], the first 19-nor lanostane derivatives of the 3,4-seco type with a spiro element, have been isolated from the leaves of Sabal causiarum and Sabal blackburniana respectively, together with the known squalene (S. blackburniana) and ss-sitosterol (S. causiarum). From leaves of Sabal peregrina, the known triterpenes 3-oxo-24-methylenecycloartane and 24-methylcycloart-25(26)-en-3-one were isolated. The structures of these compounds were established from spectroscopic studies.
Assuntos
Serenoa/química , Triterpenos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Triterpenos/isolamento & purificaçãoRESUMO
The series of naturally occurring furanonaphthoquinones is extended by identification of the derivatives 2-(1'-methylethenyl)-5-hydroxynaphtho[2,3-b]furan-4,9-dione and 2-(1'-methylethenyl)-7-hydroxynaphtho[2,3-b]furan-4,9-dione. They are accompanied in the stem barks of Newbouldia laevis by the known analogues 5-hydroxy-dehydro-iso-alpha-lapachone, 2-acetyl-5-hydroxynaphtho[2,3-b]furan-4,9-dione and 2-(1'-methylethenyl)naphtho[2,3-b]furan-4,9-dione along with the rare atraric acid and the new 2-(1'-methylethenyl)-6-hydroxy-2,3-dihydrobenzofuran. The structures of these compounds were established from spectroscopic studies.
Assuntos
Benzofuranos/isolamento & purificação , Bignoniaceae/química , Furanos/isolamento & purificação , Hidroxibenzoatos/isolamento & purificação , Naftoquinonas/isolamento & purificação , Casca de Planta/química , Benzofuranos/química , Furanos/química , Hidroxibenzoatos/química , Naftoquinonas/química , Ressonância Magnética Nuclear Biomolecular , Caules de Planta/química , Espectrometria de Massas por Ionização por Electrospray/métodosRESUMO
A new flavonol glycoside 7-O-methyl-kaempferol 4'-beta-D-galactopyranoside (rhamnocitrin 4'-beta-D-galactopyranoside) (1) was isolated from the aerial parts of Astragalus hamosus. The known flavonols hyperoside (2), isoquercitrin (3) and astragalin (4) were also identified. Structures of the compounds were elucidated by chemical and spectral methods.