RESUMEN
In the course of a phytochemical and chemotaxonomical investigation of Castanopsis species (Fagaceae), three new phenolic compounds, (3R,1'S)-[1'-(6â³-O-galloyl-ß-d-gluco-pyranosyl)oxyethyl]-3-hydroxy-dihydrofuran-2(3H)-one (1), (2R,3S)-2-[2'-(galloyl)oxyethyl]-dihydroxybutanoic acid (2), and (3S,4S)-3-hydroxymethyl-3,4-dihydro-5,6,7-trihydroxy-4-(4'-hydroxy-3'-methoxyphenyl)-1H-[2]-benzopyran-1-one (3) were isolated from the fresh leaves of Castanopsis fargesii. In addition, a known phenolic glycoside, gentisic acid 5-O-α-l-rhamnopyranosyl-(1â2)-ß-d-glucopyranoside (4) was also isolated and identified. Their structures were elucidated by means of spectroscopic methods including one- and two-dimensional NMR techniques.
Asunto(s)
Fagaceae/química , Fenoles/química , Hojas de la Planta/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Extractos Vegetales/químicaRESUMEN
Hard carbon has been widely used in anode of lithium/sodium ion battery, electrode of supercapacitor, and carbon molecular sieve for CO2 capture and hydrogen storage. In this study the lignin derived hard carbon products are investigated, and the conclusions are abstracted as follows. (1) The lignin derived hard carbon products consist of microcrystal units of sp2 graphene fragments, jointed by sp3 carbon atoms and forming sp2-sp3 hybrid hard carbon family. (2) From the lignin precursors to the sp2-sp3 hybrid hard carbon products, most carbon atoms retain their original electron configurations (sp2 or sp3) and keep their composition in lignin. (3) The architectures of lignin-derived hard carbon materials are closely dependent on the forms of their lignin precursors, and could be preformed by different pretreatment techniques. (4) The carbonization of lignin precursors follows the mechanism "carbonization in situ and recombination nearby". (5) Due to the high carbon ratio and abundant active functional groups in lignin, new activation techniques could be developed for control of pore size and pore volume. In general lignin is an excellent raw material for sp2-sp3 hybrid hard carbon products, a green and sustainable alternative resource for phenolic resin, and industrial production for lignin derived hard carbon products would be feasible.
RESUMEN
Microcrystal cellulose (MCC) is a green and sustainable resource that widely exists in various lignocellulose species in percentage 10% to 30%. The fine powder of MCC is often discarded in industrial productions that use lignocellulose as feedstock. The crystal structure of two types of MCC (sugarcane pith and bamboo pith) and their derived carbon materials are studied, and the key findings are summarized as follows. (1) In the MCC refined from sugarcane pith, there are large amount of cellulose 2D crystal, which can be converted to valuable 2D graphene crystal. (2) In the MCC refined from bamboo pith there are large amount of cluster microcrystal cellulose, which can be converted to soft and elastic graphene microcrystal (GMC). (3) The 2D cellulose in MCC of sugarcane pith has large surface area and is easily to be degraded to sugars by acid-base hydrolysis reaction, which can be carbonized to Fullerenes-like carbon spheres. (4) The crystal structures of MCC derived carbon materials are strongly impacted by the crystal structures of MCC, and the carbonization reaction of MCC follows "in situ carbonization" and "nearby recombination" mechanism. In general, the results from this study may open a new way for value-added applications of microcrystal cellulose.
RESUMEN
Three new pregnane glycosides, 3-O-ß-D-glucopyranosyl-(1â2)-α-L-arabinopyranosyl-(20R)-pregn-5-ene-3ß,20-diol (1), 3-O-α-L-arabinopyranosyl-(20R)-pregn-5-ene-3ß,20-diol-20-O-ß-D-glucopyranoside (2), 3-O-α-L-arabinopyranosyl-(20R)-pregn-5-ene-3ß,20-diol-20-O-ß-D-glucopyranosyl-(1â2)-ß-D-glucopyranoside (3) were isolated along with four known compounds, 4-7, from the leaves and stems of Brucea javanica. Their structures were determined by detailed analyses of 1D- and 2D-NMR spectroscopic data. All of the compounds isolated from Brucea javanica were tested for the antifeedant activities against the larva of Pieris rapae. Compounds 1, 3, and 5 showed significant antifeedant activities after 72 h incubation.
Asunto(s)
Depresores del Apetito/farmacología , Brucea/química , Mariposas Diurnas/efectos de los fármacos , Glicósidos/farmacología , Larva/efectos de los fármacos , Pregnanos/farmacología , Animales , Depresores del Apetito/química , Depresores del Apetito/aislamiento & purificación , Glicósidos/química , Glicósidos/aislamiento & purificación , Estructura Molecular , Pregnanos/química , Pregnanos/aislamiento & purificación , EstereoisomerismoRESUMEN
OBJECTIVE: Mutation screening was performed in a pedigree of Glanzmann's thrombasthenia (GT) and prenatal diagnosis was performed. METHODS: In this study, reverse transcription-PCR-sequencing and PCR-sequencing, as well as restriction fragment length polymorphism(RFLP) and A/T-cloned-sequencing, were used to screen the ITGA2B and ITGB3 mutation in a pedigree with Glanzmann's thrombasthenia in the RNA and DNA level. Prenatal diagnosis was performed for this pedigree. RESULTS: Deletion of 99 bps was found in the cDNA of the patient in the pedigree, leading to deletion of 33 codons (from codon 160 to 192). After genomic analysis, the patient was found to be a compound heterozygote of c.374C to G mutation and intron 4(IVS-4) + 5 G to C mutation. The two mutations were inherited from the parents. IVS-4 + 5 G to C mutation was a point mutation in the splice site, while c.374C to G mutation was out of the splice site. But both of them resulted in the same splice pattern in RNA. The two mutations were novel mutations which have not been reported in Human Gene Mutation Database (HGMD) and the mutation data base of Glanzmann's thrombasthenia. The results of ITGB3 gene screening is normal in the proband and his parents. CONCLUSION: Two novel mutation, c.374C to G and IVS-4 + 5 G to C were found in this study, which might be the cause of GT in the pedigree.
Asunto(s)
Pruebas Genéticas , Mutación/genética , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/genética , Diagnóstico Prenatal , Trombastenia/diagnóstico , Trombastenia/genética , Secuencia de Bases , Preescolar , Femenino , Orden Génico , Genotipo , Humanos , Masculino , Datos de Secuencia Molecular , Linaje , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/química , Embarazo , Conformación ProteicaRESUMEN
A new pregnane steroid and eight known compounds were isolated from Poria cum radix pini. Their structures were identified by spectroscopic data. All the known compounds were isolated from this species for the first time.
Asunto(s)
Poria/química , Pregnanos/aislamiento & purificación , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Pregnanos/químicaRESUMEN
A new triterpenoid saponin, 3-O-ß-D-xylopyranosyl spathodic acid (1), was isolated from the EtOH extract of the root of Croton lachnocarpus Benth., together with four known compounds. These compounds were characterised on the basis of their spectral data and compatible with values in the literature. Compound 1 was the first triterpenoid glucoside isolated from the genus Croton. The known compound myriaboric acid (2) showed cytotoxic activity against human hepatocellular carcinoma SMMC-7721 cell line with an IC50 value of 42.2 µM.
Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Croton/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Saponinas/aislamiento & purificación , Triterpenos/aislamiento & purificación , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Carcinoma Hepatocelular , Ensayos de Selección de Medicamentos Antitumorales , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Humanos , Neoplasias Hepáticas , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Raíces de Plantas/química , Saponinas/química , Saponinas/farmacología , Triterpenos/química , Triterpenos/farmacologíaRESUMEN
A new cardenolide tupichinolide (1) and a new steroidal saponin tupichinin A (2), together with seven known compounds, were isolated from the rhizomes of Tupistra chinensis. Their structures were established using spectroscopic analysis and chemical methods. Compound 1 was the first cardenolide isolated from Tupistra chinensis and exhibited potent cytotoxicity against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480.