RESUMO
Four hexaglycosides of methyl 3S,12S-dihydroxyhexadecanoate (1-4) were provided after treatment of the crude convolvulin fraction from Rhizoma Jalapae Braziliensis (the root of Ipomoea operculata (GOMES) MART., Convolvulaceae) with indium(III) chloride in methanol. The structures of 1-4 were elucidated on the basis of spectroscopic and chemical methods. Their sugar moieties were partially acylated with organic acids including (3S,9R)-3,6:6,9-diepoxydecanoic (exogonic) acid, (E)-2-methylbut-2-enoic (tiglic) acid, and isovaleric acid.
Assuntos
Ácidos/síntese química , Glicosídeos/síntese química , Índio/química , Metanol/química , Éteres Metílicos/síntese química , Resinas Vegetais/química , Ácidos/química , Acilação , Convolvulaceae/química , Glicosídeos/química , Éteres Metílicos/química , Estrutura Molecular , Raízes de Plantas/químicaRESUMO
Treatment of the crude ether-insoluble resin glycoside (convolvulin) from seeds of Pharbitis nil (Pharbitis Semen), called pharbitin, with indium(III) chloride in methanol provided seven oligoglycosides of hydroxy fatty acid methyl esters partially acylated by 2-methyl-3-hydroxybutyric (nilic) and 2S-methylbutyric acids. Their structures were elucidated on the basis of NMR and MS data and chemical conversions.
Assuntos
Ácidos Graxos/isolamento & purificação , Glicosídeos/isolamento & purificação , Ipomoea nil/química , Resinas Vegetais/isolamento & purificação , Ésteres , Ácidos Graxos/química , Glicosídeos/química , Índio/farmacologia , Metanol , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Plantas Medicinais , Resinas Vegetais/química , Sementes/químicaRESUMO
Two new glycosidic acids, quamoclinic acids G and H, were isolated from the glycosidic acid fraction afforded by alkaline hydrolysis of the ether-insoluble resin glycoside (convolvulin) fraction from the seeds of Quamoclit pennata BOJER. Both compounds are the first examples of bisdesmosides of glycosidic acid having the sugar linkages at C-3 of 3,11-dihydroxytetradecanoic acid (ipurolic acid) as well as at its C-11.
Assuntos
Convolvulaceae/química , Glicosídeos/química , Sementes/química , Glicosídeos/isolamento & purificação , Espectroscopia de Ressonância MagnéticaRESUMO
Alkaline hydrolysis of the ether-insoluble resin glycoside (convolvulin) fraction of the seeds of Quamoclit pennata BOJER (Convolvulaceae) provided five new glycosidic acids, quamoclinic acids B, C, D, E, and F, along with six organic acids, isobutyric, 2S-methylbutyric, tiglic, 2R,3R-nilic, 7S-hydroxydecanoic, and 7S-hydroxydodecanoic acids. These new compounds were characterized on the basis of spectroscopic data as well as chemical evidence. Quamoclinic acids E and F are the first examples of heptaglycosides of glycosidic acid.
Assuntos
Convolvulaceae/química , Éter/química , Glicosídeos/química , Resinas Vegetais/química , Sementes/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , SolubilidadeRESUMO
The present work characterizes novel FA in the royal jelly of honeybees (Apis mellifera). TLC analysis showed that the chloroform/methanol extract obtained from royal jelly consists mainly of FA. The FABMS spectrum of this extract gave several ion peaks due to compounds with higher M.W. than those of the FA so far reported. The methanol extract was found to contain unknown phospholipids. By means of reversed-phase HPLC with various solvent systems, 13 compounds were obtained in pure state. Their structures including absolute configurations were determined by chemical, NMR, and MS spectral analysis. Six compounds were identified as novel mono- or di-esters of 10-hydroxy-2E-decenoic acid in which the hydroxyl group was esterified by another FA unit, and one was hydroxy-2E-decenoic acid 10-phosphate. In addition, we demonstrated that 9-hydroxy-2E-decenoic acid exists as a mixture of optical isomers.
Assuntos
Ácidos Graxos Monoinsaturados/isolamento & purificação , Ácidos Graxos/química , Ácidos Fosfóricos/isolamento & purificação , Animais , Abelhas , Ésteres , Ácidos Graxos Monoinsaturados/química , Espectroscopia de Ressonância Magnética , Ácidos Fosfóricos/química , Espectrometria de Massas de Bombardeamento Rápido de Átomos , EstereoisomerismoRESUMO
Two new glycosidic acids, multifidinic acids F and G, were isolated from the glycosidic acid fraction afforded by alkaline hydrolysis of the ether-insoluble resin glycoside (convolvulin) fraction from the seeds of Quamoclit × multifida (syn. Q. sloteri House, Convolvulaceae), a hybrid between Q. pennata and Q. coccinea. The two compounds are the third and fourth examples of bisdesmosides of glycosidic acids having sugar linkages at C-3 of 3,11-dihydroxytetradecanoic acid (ipurolic acid) as well as at C-11.
Assuntos
Convolvulaceae/química , Glicosídeos/química , Resinas Vegetais/química , Éteres/química , Hidrólise , Sementes/químicaRESUMO
Alkaline hydrolysis of the ether-insoluble resin glycoside (convolvulin) fraction of the seeds of Quamoclit × multifida (syn. Q. sloteri House, Convolvulaceae), a hybrid between Q. pennat and Q. coccinea, gave three new glycosidic acids (maltifidinic acids C, D, and E) along with three known glycosidic acids (quamoclinic acids B, C, and D) and four organic acids (2S-methylbutyric, tiglic, 2R,3R-nilic, and 7S-hydroxydecanoic acids). The structures of the new glycosidic acids were characterized on the basis of spectroscopic data as well as chemical evidence.
Assuntos
Convolvulaceae/química , Glicosídeos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Sementes/químicaRESUMO
Alkaline hydrolysis of the ether-soluble resin glycoside (jalapin) fraction of the leaves and stems of Ipomoea digitata L. (Convolvulaceae) gave six organic acids, isobutyric, (S)-2-methylbutyric, tiglic, n-decanoic, n-dodecanoic, and cinnamic acids, and two glycosidic acids, quamoclinic acid A and operculinic acid A. Further, a new genuine resin glycoside, named digitatajalapin I, was isolated from the jalapin fraction, along with three known resin glycosides. Their structures have been determined on the basis of chemical and spectroscopic data.
Assuntos
Glicosídeos/isolamento & purificação , Ipomoea/química , Extratos Vegetais/química , Resinas Vegetais/isolamento & purificação , Hidrólise , Folhas de Planta , Caules de PlantaRESUMO
Alkaline hydrolysis of the ether-insoluble resin glycoside (convolvulin) fraction of the roots of Ipomoea operculata (GOMES) MART. (Convolvulaceae) afforded a glycosidic acid named operculinic acid H along with isovaleric, tiglic, and exogonic (3,6:6,9-diepoxydecanoic) acids. Operculinic acid H was characterized to be 3S,12S-dihydroxyhexadecanoic acid 12-O-beta-D-glucopyranosyl-(1-->3)-O-alpha-L-rhamnopyranosyl-(1-->2)-[O-beta-D-glucopyranosyl-(1-->3)]-O-beta-D-glucopyranosyl-(1-->2)-[O-alpha-L-rhamnopyranosyl-(1-->6)]-O-beta-D-glucopyranoside on the basis of spectroscopic data and chemical evidence. The absolute configuration of exogonic acid determined from the alpha-methoxy-alpha-trifluoromethylphenylacetic acid esters of the hydrogenolysis products revealed that exogonic acid exists as a mixture (ca. 1 : 1) of two epimers, (3S,6S,9R)- and (3S,6R,9R)-diepoxydecanoic acids.
Assuntos
Glicosídeos/química , Ipomoea/química , Brasil , Sequência de Carboidratos , Éter/química , Glicosídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Raízes de Plantas/química , EstereoisomerismoRESUMO
Three novel cantharidin analogues were isolated from the Chinese blister beetle, Mylabris phalerata PALL. (Meloidae), which has been used in traditional Chinese medicine for the treatment of cancer. Their structures were determined on the basis of heteronuclear multiple-bond connectivity and nuclear Overhauser effect spectroscopy experiments, and chemical data confirmed them to be so-called cantharimides, in which the anhydride oxygen atoms are replaced by the basic amino acid L-lysine, L-ornithine, and L-arginine moieties.
Assuntos
Cantaridina/análogos & derivados , Cantaridina/química , Cantaridina/isolamento & purificação , Besouros , Medicina Tradicional Chinesa , AnimaisRESUMO
Two new bis-secolabdane diterpenoids, excoecarins R1 (1) and R2 (2), were isolated from the resinous wood of Excoecaria agallocha. The structures of 1 and 2 were established on the basis of spectroscopic data interpretation and chemical evidence.