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1.
Chem Pharm Bull (Tokyo) ; 48(6): 828-31, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10866143

RESUMEN

Four new triterpene glycosides were isolated from the dried aerial parts of Thalictrum squarrosum (Ranunculaceae). They were designated as squarroside I, being a cycloartane-type glycoside, and squarrosides II, III and IV, being oleanene-type glycosides. Their structures were established by using two dimensional (2D) NMR techniques.


Asunto(s)
Glicósidos/aislamiento & purificación , Plantas Medicinales/química , Triterpenos/aislamiento & purificación , Conformación de Carbohidratos , Secuencia de Carbohidratos , Glicósidos/química , Espectroscopía de Resonancia Magnética , Medicina Tradicional China , Datos de Secuencia Molecular , Espectrometría de Masa Bombardeada por Átomos Veloces , Triterpenos/química
2.
Chem Pharm Bull (Tokyo) ; 48(4): 556-8, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10783078

RESUMEN

Four new cholestane glycosides, named abutilosides D (1), E (2), F (3) and G (4), were isolated from the fresh roots of Solanum abutiloides. By chemical and spectroscopic evidence, their structures were elucidated as 26-O-beta-D-glucopyranosyl 3beta,16alpha,26-trihydroxy-5alpha-cholestan-22-one 3-O-beta-D-xylopyranosyl-(1-->2)-alpha-L-rhamnopyranosyl-(1-->4)-beta-D- glucopyranoside and its desxylosyl compound (1 and 3, respectively), 26-O-beta-D-glucopyranosyl 3beta,16alpha,26-trihydroxycholest-5-en-22-one 3-O-beta-D-xylopyranosyl-(1-->2)-alpha-L-rhamnopyranosyl-(1-->4)-beta-D- glucopyranoside and its desxylosyl compound (2 and 4, respectively). These compounds were regarded as precursors of a dormantinone type compound on a hypothetical pathway of steroid biogenesis.


Asunto(s)
Colestanos/química , Glicósidos/química , Saponinas/química , Saponinas/aislamiento & purificación , Solanaceae/química , Espectroscopía de Resonancia Magnética , Modelos Químicos
3.
Phytochemistry ; 51(3): 449-52, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10438199

RESUMEN

Two new cycloartane-type glycosides, named aquilegiosides A and B, were isolated from the dried aerial parts of Aquilegia flabellata Sieb.et Zucc.var flabellata (Ranunculaceae). Their chemical structures have been characterized as 22S-3beta,16alpha,29-trihydroxy-cycloart-24-en-26,22-olid e 3-O-beta-D-glucopyranosyl-(1--->6)-beta-D-glucopyranosyl-(1--->2)-alpha- L-arabinopyranoside and 3-O-beta-D-glucopyranosyl-(1--->2)-alpha-L-arabinopyranoside, by chemical and spectroscopic evidence.


Asunto(s)
Glicósidos/química , Plantas/química , Saponinas/química , Triterpenos , Secuencia de Carbohidratos , Glicósidos/aislamiento & purificación , Conformación Molecular , Datos de Secuencia Molecular , Estructura Molecular , Saponinas/aislamiento & purificación
4.
Chem Pharm Bull (Tokyo) ; 44(5): 1119-21, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8689722

RESUMEN

From the roots of Solanum abutiloides, glycosides of 26-hydroxy- and 26-aminocholestane were obtained and their structures were characterized. Both of them were regarded as key intermediates in the biogenesis of steroidal alkaloids.


Asunto(s)
Colestanos , Raíces de Plantas/química , Saponinas/aislamiento & purificación , Secuencia de Carbohidratos , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Plantas , Saponinas/química , Espectrometría de Masa Bombardeada por Átomos Veloces , Espectrofotometría Infrarroja
5.
Phytochemistry ; 38(4): 939-42, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7766389

RESUMEN

Two new cycloartane-type glycosides, designated as thalictosides V and IX, were isolated from the methanolic extract of Thalictri Herba (Takatogusa), the dried aerial parts of Thalictrum sp. plants. Their chemical structures have been characterized as 3-O-monodesmoside and the 3,21-di-O-bisdesmoside of 3 beta,22 zeta,30-trihydroxycycloart-24-en-21-oic acid, by chemical and spectroscopic evidence.


Asunto(s)
Plantas/química , Saponinas/química , Triterpenos , Secuencia de Carbohidratos , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Espectrometría de Masa Bombardeada por Átomos Veloces
6.
Chem Pharm Bull (Tokyo) ; 42(1): 101-4, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8124756

RESUMEN

Five new triterpene glycosides were isolated from the methanolic extract of Thalictri Herba (Takatogusa), the dried aerial parts of Thalictrum sp. plants (Ranunculaceae). They were designated as thalictosides III (1) and IV (2), being cycloartane-type glycosides, and thalictosides VI (3), VII (4) and VIII (5), being oleanene-type glycosides. By chemical and spectroscopic evidence, their structures were elucidated as 22R-21S,23R-epoxy- and 22R-21R,23R-epoxy-21-methoxycycloart-24-en-3 beta,22,30-triol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->6)]- beta-D-glucopyranosides (1 and 2, respectively), 3-O-beta-D-glucopyranosyl-(1-->3)-alpha-L- rhamnopyranosyl-(1-->4)-beta-D-xylopyranosyl hederagenin 28-O-beta-D-glucopyranosyl ester (3) and 3-O-alpha-L-rhamnopyranosyl-(1-->3)-beta-D-glucopyranosyl-(1-->3)-alpha- L- rhamnopyranosyl-(1-->4)-beta-D-xylopyranosyl oleanolic acid and hederagenin 28-O-beta-D-glucopyranosyl esters (4 and 5, respectively).


Asunto(s)
Glicósidos/análisis , Plantas Medicinales/química , Triterpenos/análisis , Secuencia de Carbohidratos , Datos de Secuencia Molecular
7.
Ann Physiol Anthropol ; 10(2): 83-90, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2064685

RESUMEN

31P-MRS spectra were obtained from human first dorsal interosseous muscle during and after the voluntary static abduction of the index finger. Endurance tasks were performed at randomly assigned contraction levels of 15, 20, 30 and 40% of maximal voluntary contraction (MVC). Muscle pH was calculated according to Taylor et al. (1983) using chemical shift between inorganic phosphate (Pi) and phosphocreatine (PCr) on the 31P-MRS spectra. Mean values of endurance times of static contractions were 7.25, 5.33 and 3.08 minutes for 20, 30 and 40% MVC, respectively. At 15% MVC, all of the four subjects maintained contraction for 30 minutes, and the contractions were terminated at 30 minutes. Muscle pH at the onset of contractions were 7.12, 6.98, 7.01 and 7.08 for 15, 20, 30 and 40% MVC, respectively. At the end of contractions when the subject could not maintain the force level, muscle pH were 6.07, 5.97 and 5.94 for 20, 30 and 40% MVC, respectively. There was no significant difference in muscle pH at the end of contractions between three conditions by one-way ANOVA. In conclusion, there was a critical muscle pH of about 6.0 where static contractions could not be maintained.


Asunto(s)
Espectroscopía de Resonancia Magnética , Contracción Muscular/fisiología , Adulto , Análisis de Varianza , Dedos , Humanos , Concentración de Iones de Hidrógeno , Lactatos/sangre , Ácido Láctico , Masculino
9.
Arzneimittelforschung ; 30(10): 1669-79, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-6933994

RESUMEN

Sodium (6R,7R)-7-[(Z)-2-(2-amino-4-thiazoyl)-methoxyiminoacetamido]-8-oxo-5-thia-1-azabicyclo[4,2,0] oct-2-ene-2-carboxylate (ceftizoxime sodium), a new semisynthetic cephalosporin derivative, was tested for acute toxicity in various laboratory animal species, nephrotoxicity in rabbits, subacute and chronic toxicity in rats and dogs, and effect on fertility and teratogenicity in rats and rabbits. The i.v. LD50 values of ceftizoxime sodium in mice and rats were around 6000 mg/kg, and no deaths occurred in dogs after the largest dose of 3200 mg/kg. There was no evidence of nephrotoxicity of ceftizoxime sodium in rabbits after an i.v. dose of 1000 mg/kg. Clear-cut changes in subacute and chronic toxicity studies of ceftizoxime sodium were local damage at the injection site and its secondary reactions, although reversible peripheral anemia was observed in one female dog given 1000 mg/kg i.v. In the reproduction studies, ceftizoxime sodium had no adverse effects on fertility or fetal development in rats or rabbits.


Asunto(s)
Cefalosporinas/toxicidad , Reproducción/efectos de los fármacos , Animales , Ceftizoxima , Perros , Femenino , Fertilidad/efectos de los fármacos , Enfermedades Renales/inducido químicamente , Masculino , Embarazo , Conejos , Ratas , Teratógenos , Factores de Tiempo
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