RESUMEN
The aleurone layer of Oryza sativa cv. Heugjinmi yielded a new quinolone alkaloid, 4-carbomethoxy-6-hydroxy-2-quinolone (1), showing moderate antioxidative activity in a 1,1-diphenyl-2-picrylhydrazyl free-radical scavenging assay. Physical and spectroscopic evidence has determined the structure of the compound.
Asunto(s)
Alcaloides/aislamiento & purificación , Antocianinas/sangre , Antioxidantes/aislamiento & purificación , Bepridil/análogos & derivados , Depuradores de Radicales Libres/aislamiento & purificación , Oryza/química , Picratos , Quinolonas/aislamiento & purificación , Alcaloides/química , Alcaloides/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Bepridil/química , Compuestos de Bifenilo , Cromatografía , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología , Concentración 50 Inhibidora , Corea (Geográfico) , Espectrometría de Masas , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Quinolonas/química , Quinolonas/farmacología , Espectrofotometría Infrarroja , Espectrofotometría UltravioletaRESUMEN
Activity-guided fractionation of the roots of Anthriscus sylvestris resulted in the isolation and characterization of five cytotoxic compounds, deoxypodophyllotoxin (1), falcarindiol (2), and angeloyl podophyllotoxin (5) from the hexane soluble fraction and morelensin (3), bursehernin (4) from the chloroform soluble fraction. It is the first report of the occurrence of compound 5 in nature.
Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Plantas Medicinales/química , Antineoplásicos Fitogénicos/química , Humanos , Espectroscopía de Resonancia Magnética , Células Tumorales CultivadasRESUMEN
A part of the genome of dengue virus type 2 spanning the coding region from the carboxy terminus of the envelope protein E to the beginning of the NS3 protein was expressed using recombinant vaccinia virus. Additional constructs which contained open reading frames terminating within the NS1 or NS2A genes were also expressed. NS1 dimers were formed by extended NS1 molecules containing 61 amino acids of NS2A. No dimers were detected when NS1 was shortened by 79 amino acids at its carboxy terminus.
Asunto(s)
Cápside/genética , Virus del Dengue/genética , Genes Virales , Proteínas del Núcleo Viral/genética , Animales , Western Blotting , Cápside/biosíntesis , Línea Celular , Clonación Molecular , Expresión Génica , Humanos , Ratones , Transfección , Virus Vaccinia/genética , Proteínas del Núcleo Viral/biosíntesis , Proteínas no Estructurales ViralesRESUMEN
Two sapogenins isolated from MELANDRIUM FIRMUM are shown to have the structures of 3beta,21beta-dihydroxy-16,23,dioxo-28-nor-17alpha,18beta-olean-12-ene and 3beta-16alpha-dihydroxy-23-oxo-olean-13(18)-en-28-oic acid, respectively by spectral data and X-ray crystallographic analysis.
RESUMEN
The nucleotide sequence and the deduced amino acid sequence for the genes encoding the structural proteins of two strains of dengue virus type 2 (DEN-2) were determined from cDNA clones. The genes for C, prM(M) and E proteins were sequenced for the prototype DEN-2 virus, the New Guinea C strain. Also sequenced were the prM(M) and E genes of PUO-218. This strain of DEN-2 was isolated during 1980 in Bangkok and had received a limited number of laboratory passages. Comparisons of the newly determined sequences with those published for the Jamaica 1409 and Puerto Rico PR-159 (S1 vaccine candidate) strains revealed a close relationship between New Guinea C virus and both the Jamaica and PUO-218 viruses (greater than 96% similarity in nucleotides of the E gene), whereas S1 virus was the most divergent.
Asunto(s)
Virus del Dengue/genética , Proteínas Virales/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , ADN Viral/genética , Virus del Dengue/clasificación , Genes Virales , Humanos , Datos de Secuencia Molecular , Proteínas Estructurales ViralesRESUMEN
Two new monodesmosidic saponins (Phytolaccosides F and D (2)) have been isolated from the roots of PHYTOLACCA AMERICANA and identified as 3- O-[alpha- L-rhamnopyranosyl(1-->2)-beta- D-glucopyranosyl (1-->2)-beta- D-xylopyranosyl]phytolaccagenic acid and 3- O-[beta- D-glucopyranosyl(1-->2)-beta- D-xylopyranosyl]phytolaccagenic acid, respectively.
RESUMEN
Four saponins were isolated from the roots of PATRINIA SCABIOSAEFOLIA (Valerianaceae) and identified as 3- O-alpha- L-arabinopyranosylhederagenin 28- O-beta- D-glucopyranosyl(1-->6)-beta- D-glucopyranoside ( 2) and its 2'-acetate ( 1) and 3- O-beta- D-glucopyranosyl(1-->3)-alpha- L-rhamnopyranosyl(1-->2)-alpha- L-arabinopyranosyloleanolic acid ( 3) and its 28- O-beta D-glucopyranosyl(1-->6)-beta- D-glucopyranoside ( 4).
RESUMEN
Treatment of 28-hydroxyolean-12-enes with N-bromosuccinimide (NBS) in acetonitrile at room temperature afforded 12 alpha-bromooleanan-13beta, 28-epoxides in high yield. This reaction resulted in the formation of olean-9 (11), 12-diene-18alpha, 29-epoxides from 29-hydroxy isomers but recovered only starting materials from 30-hydroxy isomers. NBS will be used a reagent for diagnostic tool to distinguish between isomers bearing a primary hydroxyl group on D/E rings of olean-12-enes.
RESUMEN
By TLC, DCC and HPLC analysis, ginsenoside compositions of ginseng tissue culture and juice showed distinct features of fresh materials by a high proportion of "polar saponins" and low panaxadiol/panaxatriol ratio.
Asunto(s)
Panax/análisis , Plantas Medicinales , Saponinas/análisis , Cromatografía Líquida de Alta Presión , Cromatografía en Capa Delgada , Ginsenósidos , Corea (Geográfico) , Triterpenos/análisisAsunto(s)
Cumarinas/farmacología , Hígado/enzimología , Oxigenasas de Función Mixta/antagonistas & inhibidores , Oxidorreductasas N-Desmetilantes/antagonistas & inhibidores , Animales , Hexobarbital/metabolismo , Hexobarbital/farmacología , Masculino , Ratones , Ratas , Ratas Endogámicas , Sueño/efectos de los fármacos , Relación Estructura-ActividadRESUMEN
A new method for separation and quantitative determination of flavone-C-glycosides in seeds of Zizyphus vulgaris var. spinosus by high performance liquid chromatography was elaborated. A reverse-phase system with a COPELL-ODS column using tetrahydrofuran in water (4:53) as a mobile phase was developed. The flavonoids were detected at 330 nm and the analysis was successfully carried out within 15 min.
