RESUMEN
Six groups of diastereomeric 2,4-disubstituted adamantanes were studied with DFT-GIAO-NBO (natural orbital analysis) methods. The calculated (13)C chemical shifts reproduce well the experimental data. It was found that among all diastereomers, those bearing substituents in delta-syn-axial positions showed the largest overall deshielding, i.e. the sum of all (13)C chemical shifts [Sigmadelta((13)C)] was the greatest and also had the highest delocalization contribution to the molecular energy evaluated with NBO. The higher delocalization energy is proposed to be the origin of the deshielding delta-syn-axial effect.
RESUMEN
Achillea species are widely used in folk medicine for treatment of inflammatory diseases. The inhibitory effect on the human neutrophils respiratory burst activity of total extracts, their fractions and some main constituents of the flower heads from Achillea asplenifolia, A. collina and A. distans belonging to A. millefolium complex of Bulgarian origin, were tested by the modified method of Tan and Berridge. Seven from the investigated fractions showed activity similar or higher than that of indomethacine and might be evaluated as nonsteroidal anti-inflammatory agents.
Asunto(s)
Achillea/química , Antiinflamatorios no Esteroideos/aislamiento & purificación , Antiinflamatorios no Esteroideos/farmacología , Lactonas/aislamiento & purificación , Lactonas/farmacología , Neutrófilos/efectos de los fármacos , Plantas Medicinales/química , Antiinflamatorios no Esteroideos/química , Bulgaria , Humanos , Indometacina/farmacocinética , Indometacina/farmacología , Lactonas/química , Medicina Tradicional , Estallido RespiratorioRESUMEN
Two novel triterpenoid saponins, Snatzkein C, (3beta, 20-dihydroxylupan-28-oic acid 3-O-[beta-D-galactopyranosyl-(1-->2)-beta-D-glucopyranosyl-28- O-beta-D-glucopyranoside) and Snatzkein D, (3beta, 20-dihydroxylupan-28-oic acid 3-O-[beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl]-28-O-beta-D-++ +glucopyranoside), have been isolated from Arenaria filicaulis. Their structure and conformational behaviour were elucidated by one- and two-dimensional 1H NMR and 13C NMR spectroscopy.
Asunto(s)
Saponinas/química , Triterpenos/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Modelos Moleculares , Conformación Molecular , Datos de Secuencia Molecular , Resonancia Magnética Nuclear Biomolecular , Saponinas/aislamiento & purificación , Triterpenos/aislamiento & purificaciónRESUMEN
Four novel triterpenoid saponins have been isolated from Gypsophila capillaris. Three were monodesmosidic: 3 beta-hydroxyolean-12-en-23,28-dioic acid 28-O-[beta-D-glucopyranosyl-(1-->3)-beta-D-glucopyranosyl-(1-->2)] [beta-D-galactopyranosyl(1-->6)]beta-D-glucopyranoside, 3 beta-hydroxyolean-12-en-23-oxo-28-oic acid 28-O-[beta-D-glucopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->3)] [beta-D-glucopyranosyl(1-->6)]beta-D-galactopyranoside, 3 beta-hydroxyolean-12-en-23,28-dioic acid 28-O-[beta-D-glucopyranosyl-(1-->2)-beta-D-galactopyranosyl-(1-->3)] [beta-D-glucopyranosyl(1-->6)]beta-D-galactopyranoside. The fourth was bisdesmosidic: 3 beta-hydroxyolean-12-en-23,28-dioic acid 23-O-beta-D-glucopyranosyl-28-O-[beta-D-glucopyranosyl-(1-->2)-beta-D- galactopyranosyl-(1-->3)][beta-D-glucopyranosyl-(1-->6)]beta-D- galactopyranoside. The structures of the compounds were elucidated by 1D and 2D NMR techniques and from other spectroscopic evidence.
Asunto(s)
Plantas Medicinales/química , Saponinas/química , Triterpenos/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Egipto , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Estructura Molecular , Oligosacáridos/química , Oligosacáridos/aislamiento & purificación , Saponinas/aislamiento & purificación , Espectrometría de Masa Bombardeada por Átomos Veloces , Triterpenos/aislamiento & purificaciónRESUMEN
The structure of crotaramosmin has been reassigned to 1-(5-hydroxy-2, 2-dimethyl-2H-chromen-6-yl)-3-(4-hydroxyphenyl)-propanone (1) as determined by extensive NMR investigation.
RESUMEN
The structure elucidation of a new saponin from Arenaria filicaulis (Boiss.), Caryophyllaceae, Snatzkein F (1), containing gypsogenin with a tetrasaccharide moiety was accomplished by use of 1D and 2D NMR methods.
RESUMEN
The oligosaccharide core region, beta-D-Glcp-(1----3)-beta-D-Glcp-(1----4)-alpha-D-Glcp- 1----1)-alpha-D-Glcp (1), of the lipo-oligosaccharide-type antigens isolated from M. kansasii has been synthesised from 2,3,2',3',4',6'-hexa-O-benzyl-6-O-(1-phenylethyl)-alpha, alpha-trehalose (4). Compound 4 was obtained by LiAlH4-AlCl3-type hydrogenolysis of 2,3,2',3',4',6'-hexa-O-benzyl-4,6-O-(S)-(1-phenylethylidene)-alpha , alpha-trehalose. The beta-laminaribiosyl part of the molecule was built-up by sequential glycosylation steps using 2,4,6-tri-O-acetyl-3-O-allyl-alpha-D-glucopyranosyl bromide in the presence of HgBr2 and methyl 2,3,4,6-tetra-O-acetyl-1-thio-beta-D-glucopyranoside promoted by methyl triflate. The complete a priori 13C-n.m.r. spectrum assignment of 1 was achieved by applying 2D methods.
Asunto(s)
Lipopolisacáridos/síntesis química , Mycobacterium/inmunología , Oligosacáridos/síntesis química , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Rotación ÓpticaRESUMEN
The title tetrasaccharide having the structure 3-O-Me-beta-L-Xylp-(1----4)- alpha-L-Rhap-(1----4)-alpha-L-Rhap-(1----2)-L-Rhap was obtained by reaction of the alpha-acetobromo derivative of 4-O-(3-O-methyl-beta-L-xylopyranosyl)-L-rhamnopyranose and benzyl 3,4-di-O-benzyl-2-O-(2,3-O-isopropylidene-alpha-L-rhamnopyranosyl)- alpha-L-rhamnopyranoside, followed by removal of the protecting groups. The synthesised compounds were characterised on the basis of n.m.r. data.
Asunto(s)
Lipopolisacáridos/síntesis química , Oligosacáridos/síntesis química , Pseudomonas/inmunología , Secuencia de Carbohidratos , Cromatografía en Capa Delgada , Indicadores y Reactivos , Lipopolisacáridos/aislamiento & purificación , Espectroscopía de Resonancia MagnéticaRESUMEN
The syntheses of 5-pyridyl-3(beta-D-galactopyranosyl)-1,3,4-oxadiazole-2-thiones 3a-3c and 5-pyridyl-2(beta-D-galactopyranosyl)-4-benzyl-1,2, 4-triazole-3-thiones 6a-6c are reported. The existence of N-galactosides--not S-galactosides--was proven by IR and 15N NMR spectroscopy. The structures of the final products and the intermediates were elucidated by IR, 1H, 13C and 15N NMR spectroscopy and mass spectrometry.
Asunto(s)
Galactósidos/química , Galactósidos/síntesis química , Oxadiazoles/química , Tionas/química , Triazoles/química , Cromatografía en Capa Delgada , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Oxadiazoles/síntesis química , Espectrofotometría Infrarroja , Tionas/síntesis química , Triazoles/síntesis químicaRESUMEN
Fractions of methanol, dichloromethane, water extracts and volatiles of Carthamus lanatus aerial parts given by oral route at a dose of 2 mg/kg showed significant antiinflammatory activities in rats. On the contrary, only the water fraction of MeOH extract possesses a significant analgesic activity.
Asunto(s)
Analgésicos/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Carthamus , Edema/prevención & control , Dolor/prevención & control , Fitoterapia , Extractos Vegetales/uso terapéutico , Administración Oral , Analgésicos/administración & dosificación , Analgésicos/farmacología , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/farmacología , Carragenina , Edema/inducido químicamente , Masculino , Dimensión del Dolor/efectos de los fármacos , Componentes Aéreos de las Plantas , Extractos Vegetales/administración & dosificación , Extractos Vegetales/farmacología , Presión , Ratas , Ratas WistarRESUMEN
Five pentacyclic triterpenoids have been isolated from the minor constituents of local liquorice roots, one of them has not been isolated before from liquorice root. Their structural formulae and stereochemical configuration was determined by spectroscopic methods. 13C and 1H NMR data have been compiled.
Asunto(s)
Glycyrrhiza/análisis , Plantas Medicinales , Triterpenos/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Estructura Molecular , Triterpenos/químicaRESUMEN
Enantiomeric ratios of compounds with P=S functionalities can be determined by 1H, 13C, and 31P NMR spectroscopic inspection of their diastereomeric complexes with (R)-Rh2(MTPA)4 (MTPA-H identical with methoxytrifluoromethylphenylacetic acid; Mosher's acid). This is the first facile and rapid spectroscopic method for chiral recognition in this class of compounds. Whereas complexation shifts Deltadelta are moderate or even negligible, significant signal dispersions Delta(nu) can be observed. Some rationalization about the complexation mode is presented. The NMR spectral characteristics of the free P=S compounds 1-9 are described in detail.
RESUMEN
The isolation and structure elucidation of gedunin [1], the antimalarial agent of Azadirachta indica, are reported. Its 1H- and 13C-nmr spectra were assigned by using one- and two-dimensional nmr spectroscopy, especially homonuclear and heteronuclear COSY, nOe difference, and COLOC experiments.
Asunto(s)
Antimaláricos/aislamiento & purificación , Plantas/análisis , Espectroscopía de Resonancia Magnética , Estructura MolecularRESUMEN
From the bark of ACACIA NILOTICA subsp. TOMENTOSA a novel polyphenol, (+)-catechin-5-galloyl ester ( 5), was isolated along with gallic acid ( 1), its methyl ester ( 2), naringenin ( 3), and (+)-catechin ( 4). The structure of 5 was determined by use of mass spectrometry as well as (1)H- and (13)C-NMR spectroscopy.