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1.
A new phenolic glycoside from the roots of Lygodium japonicum 总被引：1，自引：0，他引：1
A new phenolic glycoside, 3,4-dihydroxybenzoic acid 4-O-(4'-O-methyl)-beta-D-glucopyranoside (1), was isolated from the roots of Lygodium japonicum. The structure was elucidated on the basis of spectroscopic methods. 相似文献
2.
Nattaya Lourith Takeshi Katayama Kimiko Ishikawa Toshisada Suzuki 《Journal of Wood Science》2005,51(4):379-386
To investigate the biosynthesis and stereochemistry of syringylglycerol-8-O-4′-(sinapyl alcohol) ether (SGSE), a syringyl 8-O-4′ neolignan, feeding experiments and enzyme assays using Eucommia ulmoides were carried out. Diastereoselective formation of erythro-SGSE was found. When [8-14C]sinapyl alcohol was administered to excised shoots of E. ulmoides, 14C was incorporated into free SGSE and SGSE glucosides. In stems, incorporation into (+)-erythro-[14C]SGSE (0.037%) with 9.1% enantiomeric excess (% e.e.) was found; incorporation into the threo isomer was not detectable. Erythro-[14C]SGSE glucosides (0.047%) dominated over threo forms (0.007%) with 74.0% diastereomeric excess (% d.e.); both diastereomers were levorotatory with 32.0% e.e. and 18.3% e.e., respectively. In leaves, higher incorporation into (−)-erythro-[14C]SGSE (0.500%, 15.9% e.e.) than into the threo isomer (0.206%, 7.4% e.e.) was observed (41.6% d.e.). (−)-Erythro-[14C]SGSE glucosides (1.692%, 25.0% e.e.) were produced at higher rates than threo isomers (0.177%, 16.4% e.e.) with 81.0% d.e. In incubations of a mixture of [8-14C]sinapyl and [8-14C]coniferyl alcohols with an insoluble enzyme preparation from stems of E. ulmoides, erythro-SGSE was preferentially produced. The highest % d.e. (82.8) was observed at 60 min with the (+)-erythro isomer (21.4% e.e.) and the (−)-threo form (4.3% e.e.).Part of this report was presented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, April 2002, and the 47th Lignin Symposium, Fukuoka, October 2002 相似文献
3.
A series of novel 4-O-alkoxytrityl chlorides (1) with different chain lengths was synthesized as a novel reagent for obtaining 6-O-alkylated cellulose with high regioselectivity via trityl groups in one reaction step without the use of any protective groups. These chlorides were reacted with methyl -d-glucoside, which was used as a model compound, to examine the reactivities toward the primary hydroxyl groups of cellulose to afford a series of 6-O-alkylated methyl -d-glucosides in high yields. The product compounds were found to have interesting solubilities and thermal properties. Thus, newly prepared trityl chloride derivatives were found to be useful regioselective derivatization reagents on the primary hydroxyl group in carbohydrates, especially in cellulose. 相似文献
4.
Moracin M (1), Steppogenin-4′-O-β-D-glucosiade (2), Mullberroside A (3) were isolated from the root bark of Morus alba L. and identified by spectral evidence. Compounds 1, 2 and 3 were studied in hypoglycemic effects on alloxan-diabetic mice. The results showed that compounds 1, 2 and 3 all produced hypoglycemic effects. The compound 2 in a dose of 50 mg/kg exerted significant effect (p < 0.05), 2 and 3 in a dose of 100 mg/kg exerted obviously effect (p < 0.01). Meantime, the compound 1 in a dose of 100 mg/kg can make the fasting blood glucose level have decreasing tendency. 相似文献
5.
Sung SH 《Fitoterapia》2006,77(6):487-488
A new tetrahydrofuradineolignan, called 4-O-demethylmanassantin A (1) was isolated from underground parts of Saururus chinensis together with three known dineolignans, 4-O-demethylmanassantin B (2), manassantin A (3) and manassantin B (4). 相似文献
6.
A new chromone glycoside (1), 7-O-(6'-galloyl)-beta-D-glucopyranosyl-5-hydroxychromone was isolated from Polygonum capitatum. 相似文献
7.
From the husks of Xanthoceras sorbifolia, a new coumarin glycoside, isofraxetin-6-O-beta-D-glucopyranoside (1), was isolated. The structure was established on the basis of spectroscopic methods. 相似文献
8.
Yoh-ichi Matsushita Kazuhiro Sugamoto Kenji Miyakubo Chiaki Kurogi Takanao Matsui Hisato Oda Hideto Fujimoto 《Journal of Wood Science》2008,54(6):476-482
Sawdusts of sugi (Cryptomeria japonica) wood prepared before and after steam drying at 120°C in a kiln were extracted with n-hexane and ethyl acetate to give n-hexane extracts and ethyl acetate extracts. From gas chromatography-mass spectrometry analysis of the ethyl acetate extracts
from woods before and after steam drying, the components of 4-epi-cubebol, cubebol, and 2,7(14),10-bis-abolatrien-1-ol-4-one, which existed in the raw sugi wood, were proved to disappear
in the steam-dried wood. These components were also absent in the ethyl acetate extract of the steam-condensed solution of
waste steam from the kiln outlet. When these three components were treated with 0.2% (v/v) acetic acid solution at 120°C,
δ-cadinene was produced as a major product from both 4-epi-cubebol and cubebol by dehydration and cleavage of the cyclopropane ring, and cryptomerone from 2,7(14),10-bisabolatrien-1-ol-4-one
by hydration. The chemical changes of the three components presumably occur during steam drying of the sugi wood.
This study was presented in part at the 85th Spring Meeting of the Chemical Society of Japan, Kanagawa, Japan, March 26–29,
2005 相似文献
9.
Nawwar M Hussein S Ayoub N Hashim A El-Sharawy R Lindequist U Harms M Wende K 《Fitoterapia》2011,82(8):1265-1271
Assessment of the UV protecting potential of an aqueous methanol leaf extract of Harpephyllum caffrum proved that it possesses a distinct radical scavenging effect and inhibits the production of the proinflammatory cytokine IL-6 by human keratinocytes (HaCaT cells) following UV radiation. Phytochemical investigation of this extract led to isolation and structural determination of the hitherto unknown phenolics, kaempferol 3-O-(2″-sulphatogalactopyranoside), its quercetin analogue and 3-methoxyellagic acid 4-O-galactopyranoside in addition to 18 known phenolic compounds. The structures were determined by spectroscopic and conventional methods of analysis. Flavonoid sulphatoglycosides which have been rarely found in nature were major phenolic constituents of this plant, and this is the first report of the isolation of any of them from Anacardiaceae. The extract was found to diminish UV phototoxic reaction of keratinocytes. However, the isolated kaempferol sulphatogalactopyranoside did not interact with UVB triggered IL-6 production of HaCaT keratinocytes. 相似文献
10.
The methyl ester of diosmetin 7-O-beta-D-glucuronide (1) was isolated from the fruits of Luffa cylindrica. Its structure was determined by spectroscopic methods. 相似文献
11.
A new flavonoid, 3,7-dihydroxy-8-methoxyflavone 7-O-α-
-rhamnopyranosyl-(1→4)-α-
-rhamnopyranosyl-(1→6)-β-
-glucopyranoside (1), was isolated from the seeds of Shorea robusta. 相似文献
12.
Three new monoterpene glycosides named 4-O-methyl-paeoniflorin (1), isopaeoniflorin (2), and isobenzoylpaeoniflorin (3), together with two known monoterpene glycosides, paeoniflorin (4) and benzoylpaeoniflorin (5), were isolated from the roots of Paeonia lactiflora. Their structures were established on the basis of spectral and chemical evidence. 相似文献
13.
A new monoterpene glycoside, 4-O-methyl-4'-hydroxy-3'-methoxy-paeoniflorin (1), was isolated from the root cortex of Paeonia delavayi along with the known paeoniflorin, oxypaeoniflorin, benzoylpaeoniflorin, benzoyloxypaeoniflorin, albiflorin and a paeonilactone-A. 相似文献
14.
Four steroidal saponins were isolated from the leaves of Furcraea selloa var. marginata. These included one furostanol saponin, furcreafurostatin (1), and three known spirostanol saponins, furcreastatin (3), yuccaloeside C (4) and cantalasaponin-1 (5). The 22-O-methyl ether (2) of furcreafurostatin (1) was also characterized. The structures were determined by using a combination of spectroscopic techniques. 相似文献
15.
A new phenolic glycoside, 3,5-dimethyl-6-hydroxy-2-methoxy-4-O-D-glucopyranosyl-oxy-acetophenone (1), was isolated from the aerial parts of Dryopteris fragrans. The structure was elucidated on the basis of spectroscopic methods. 相似文献
16.
Patricia Rodríguez Freddy Gonzlez-Mujica Jairo Bermúdez Masahisa Hasegawa 《Fitoterapia》2010,81(8):1220-1223
Glucose intestinal absorption (GIA) is one of the factors that increase glycemia. Its reduction could be an important factor in decreasing hyperglycemia in diabetic patients. It has been shown that the aqueous extract of Bauhinia megalandra leaves inhibits GIA. In the present study we identified a compound present in the extract of B. megalandra responsible for the biological effect. The methanol extract of B. megalandra leaves was fractionated using different solvents, and high-speed counter-current chromatography yielding two pure compounds identified by 1H NMR and 13C NMR as kaempferol 3-O-α-rhamnoside and quercetin 3-O-α-rhamnoside. The first one increased the KM without changes in the VMAX of GIA. In addition it exerted an additive inhibitory effect, on GIA, when combined with phlorizin. We suggest that kaempferol 3-O-α-rhamnoside is a competitive inhibitor of intestinal SGLT1 cotransporter. 相似文献
17.
Shingo Kawai Kyousuke Nakata Masako Ohashi Tomoaki Nishida 《Journal of Wood Science》2008,54(3):256-260
After feeding experiments of Myrica rubra young shoots with 4-[8,9-13C2]coumaric acid, mass spectrometric analyses revealed that the cyclic diarylheptanoids, myricanol and myricanone, were derived
from two molecules of 4-coumaric acid. 13C Nuclear magnetic resonance analysis of myricanol isolated after administration of 4-[8,9-13C2]coumaric acid demonstrated that the C-8 and C-9 atoms of 4-coumaric acid are incorporated into C-8, C-9, C-11, and C-12 of
the corresponding myricanol.
Part of this report was presented at the 56th Annual Meeting of the Japan Wood Research Society, Akita, August 2006 相似文献
18.
Sugi (Cryptomeria japonica D. Don) wood was treated with supercritical water (374°C, 22.1MPa), and fractionated into the water-soluble portion, the methanol-soluble portion, and the methanol-insoluble residue. The methanol-soluble portion mainly consisted of the lignin-derived products. To characterize the compounds in the methanol-soluble portion, gel permeation chromatographic (GPC) and gas chromatographic-mass spectrometric (GC-MS) analyses were performed. The GPC analysis indicated that the methanol-soluble portion contained lignin-derived monomeric and dimeric products. GC-MS analysis detected 31 products which were expected to be monomeric compounds, and 18 of these were identified to be guaiacol, methylguaiacol, ethylguaiacol, vinylguaiacol, eugenol, propylguaiacol, vanillin, cis-isoeugenol, homovanillin, trans-isoeugenol, acetoguaiacone, propioguaiacone, guaiacylacetone, 2-methoxy-4-(1-hydroxypropyl)phenol, homovanillic acid, 2-methoxy-4-(prop-1-en-3-one)phenol, coniferyl aldehyde, and ferulic acid. In addition, 22 dimeric products were detected, and 4 of these were believed to be compounds with biphenyl type (5-5), diphenylethane type (-1), stilbene type (-1), and phenylcoumaran type (-5) structures. These results clearly indicated that the methanol-soluble portion included various monomeric and dimeric compounds produced as a result of the cleavage of ether linkages and propyl chains of lignin. 相似文献
19.
Aqueous and alcoholic extracts, volatile oil and four flavonoids, xanthomicrol (1), kumatokenin (2), jaceidin (3) and 3, 3'-di-O-methylquercetin (4), isolated from Varthemia iphionoides were investigated for their in vitro anti-platelet activity. Aqueous extract and compounds (1), (2) and (4) showed anti-platelet activity. Volatile oil and the alcoholic extract did not exhibit any anti-platelet activity. Structures of the isolated compounds (1)-(4) were determined by spectroscopic methods (UV, IR, MS, (1)H-NMR). 相似文献
20.
Dias KS Marques MS Menezes IA Santos TC Silva AB Estevam CS Sant'Ana AE Pizza C Antoniolli AR Marçal RM 《Fitoterapia》2007,78(7-8):460-464
Ethanol extract of Maytenus rigida stem bark and its fractions were assessed for antinociceptive activity in tail-flick test in rats. The activity was located in the chloroform, ethyl acetate and aq.methanol fractions. Phytochemical screening revealed that catechin was the only common class of compounds present on the ethanol extract as well as on the active fractions. 4'-Methylepigallocatechin, isolated from the ethyl acetate and aq.methanol fractions, showed antinociceptive effect in the tail-flick test (75 mg/kg; p.o.), which was reversed by the opiate antagonist naloxone (3 mg/kg; i.p.). 相似文献