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1.
A new isoflavonol triglycoside, biochanin A 7-O-β-
-apiofuranosyl-(1→5)-β-
-apiofuranosyl-(1→6)-β-
-glucopyranoside (1), was isolated from Andira inermis roots in addition to the known compounds genistein 7-O-β-
-apiofuranosyl-(1→6)-β-
-glucopyranoside and lanceolarin. 相似文献
2.
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
3.
A new phenolic glucoside ester, 6'-E-(2'-methyl-2'-butenoyl) arbutin (1), was isolated from the leaves of Heliciopsis lobata. Its structure was elucidated by spectral analysis. 相似文献
4.
Nine phenolic compounds, including a new one, were isolated from 70% acetone extract of Craspedolobium schochii. The new compound was identified as 3-(3,4-dimethoxy-2-hydroxyphenyl)-7-hydroxy-coumarin (1) on the basis of spectroscopic evidence. 相似文献
5.
Rauter AP Branco I Lopes RG Justino J Silva FV Noronha JP Cabrita EJ Brouard I Bermejo J 《Fitoterapia》2007,78(7-8):474-481
A new lupene triterpenetriol was isolated from the acetone extract of the aerial parts of Salvia sclareoides and characterised as (1beta,3beta)-lup-20(29)-ene-1,3,30-triol (1). In addition, nepetidin (2), nepeticin (3), lupendiol (4), (1beta,11alpha)-dihydroxy-lup-20(29)-en-3-one (5), ursolic acid (6), sumaresinolic acid (7) and hederagenin (8), were identified in this Salvia sp. To the best of our knowledge, the compounds 2 and 7 are new constituents in Salvia spp. The acetone, ethanol, butanol and water extracts of the plant were screened for the in vitro inhibitory activity of acetylcholinesterase (AChE) and butyrilcholinesterase (BChE), enzymes which play a role in the Alzheimer disease. All extracts inhibited acetylcholinesterase activity at 10 microg/ml, a remarkable activity since the standard drug rivastigmine does not inhibit acetylcholinesterase at the same concentration. Regarding the butyrilcholinesterase, the acetone extract at 1000 microg/ml was able to inhibit completely the enzyme activity and the butanol and ethanol extracts, at this concentration, produced a potent inhibition of BchE. 相似文献
6.
A new megastigmane diglycoside was isolated from the leaves of Carallia brachiata. The structure was determined by spectroscopic methods as 3-hydroxy-5,6-epoxy-beta-ionol -3-O-beta-apiofuranosyl-(1-->6)-beta-glucopyranoside (1). Additionally, 29 known compounds consisting of two megastigmanes, one 1,2-dithiolane derivative, seven aromatic compounds, five condensed tannins, 12 flavonoids, and two glyceroglycolipids were isolated and identified. 相似文献
7.
Two compounds were isolated from the leaves of Panax ginseng. Their structures were identified as 3beta,6alpha,12beta-triol-22,23,24,25,26,27-hexanordammaran-20-one, and dammar-20(22),24-diene-3beta,6alpha,12beta-triol by spectral and chemical methods. The complete signal assignments of the two compounds were carried out by means of 2D NMR spectral analysis. 相似文献
8.
The chloroform extract of the stem bark of Lamprothamnus zanguebaricus has yielded two ethanones; 1-(3-hydroxy-4-methoxy-5-methylphenyl)ethanone (I) (a new compound) and 1-(3-hydroxy-4-methoxyphenyl)ethanone (II). The structures of both compounds were established by spectroscopic methods. 相似文献
9.
Trans-2,2',4,4'-tetramethyl-6,6'-dinitroazobenzene from the leaves of Aconitum sungpanense was reported as a new compound. The structure was determined by spectroscopic methods and X-ray diffraction analysis. 相似文献
10.
A new phenolic glycoside , 2-methoxy-5-(E)-propenyl-phenol-beta-vicianoside, was isolated from the root of Paeonia lactiflora. The structure of the new glycoside was elucidated by chemical and spectroscopic methods. 相似文献
11.
A new chromone glycoside (1), 7-O-(6'-galloyl)-beta-D-glucopyranosyl-5-hydroxychromone was isolated from Polygonum capitatum. 相似文献
12.
以β-蒎烯为原料,先经氧化反应合成诺蒎酮,诺蒎酮与水杨醛进一步经羟醛缩合反应合成了3-(2'-羟基亚苄基)诺蒎酮,通过单因素和正交试验优化了缩合反应的工艺条件。结果表明:缩合反应的优化工艺条件为:诺蒎酮1.43 g,以30 m L叔丁醇为溶剂,2.5 g叔丁醇钾为催化剂,n(诺蒎酮)∶n(水杨醛)为1.0∶1.2,回流反应2 h,产物得率为79.46%。采用MS、IR、NMR、X射线单晶衍射等对3-(2'-羟基亚苄基)诺蒎酮的结构进行了表征,确认了化合物的结构,该化合物的晶体属单斜晶系,P212121空间群。对3-(2'-羟基亚苄基)诺蒎酮的酸碱指示性能进行了研究,结果表明:该化合物滴定0.257 4 mol/L盐酸标准溶液时,指示颜色为橘黄色,测定的盐酸浓度为0.259 6 mol/L,RSD为0.089%,滴定的灵敏度高、偏差小,效果优于酚酞指示剂。 相似文献
13.
The content of the glyceraldehyde-2-aryl ether-type structure in water-soluble lignin–carbohydrate complex (LCC) fractions, which were obtained from Japanese cedar and birch residual wood meal after milled wood lignin isolation, was determined by ozonation. Quite high amounts of the glyceraldehyde-2-aryl ether-type structure were found in water-soluble LCC fractions of both species; about 3–5 times higher than those of other fractions. This result, as well as the high content of the β-1 structure in these fractions shown in our previous reports, suggest that lignin in these fractions has the characteristics of endwise-type lignin, because the glyceraldehyde-2-aryl ether-type structure and β-1 structure are typical characteristics of this type of lignin fraction. These results are in good agreement with the generally accepted hypothesis that the glyceraldehyde-2-aryl ether-type structure and β-1 structure are generated at the same time by a radical coupling reaction. The results also indicated that these two structures are present in close proximity in the lignin. 相似文献
14.
研究了以(2R,4aS)-异长叶烯酮为原料合成α-溴代异长叶烯酮的溴代反应。采用乙酸乙酯为溶剂,异长叶烯酮与溴化铜进行溴代反应得到两种同分异构体,经制备液相色谱分离纯化后,用~1H NMR,FT-IR,GC-MS,比旋光度和X射线单晶衍射等分析手段,确定其结构分别为(2R,4aR,6R)-(+)-6-Br-异长叶烯酮液体([α]_D~(25)+81°)和(2R,4aR,6S)-(-)-6-Br-异长叶烯酮晶体([α]_D~(25)-58°);探讨了制备工艺条件对溴代产物的影响。结果表明:在以乙醇为溶剂、溴化铜为溴代试剂的反应体系中,异长叶烯酮能选择性溴代生成(2R,4aR,6S)-(-)-6-Br-异长叶烯酮,且最佳制备工艺条件为异长叶烯酮6.54 g(0.03 mol),溴化铜与异长叶烯酮的物质的量之比为3∶1,溶剂乙醇用量60 m L,反应温度为78℃,反应时间为3 h。在此条件下,异长烯酮转化率为95.72%,(2R,4aR,6S)-(-)-6-Br-异长叶烯酮的得率为88.39%。 相似文献
15.
以天然亚茴香基丙酮为原料,Lewis酸为催化剂,环己烷为氢源,研究了天然茴香基丙酮的合成工艺,并探讨反应机理和反应的选择性。对不同Lewis酸催化剂与溶剂进行筛选,确定Al Cl3为催化剂,CH2Cl2为溶剂,采用正交试验方法对茴香基丙酮合成工艺进行优化,得到最佳工艺条件。在反应温度35℃,反应时间4 h,n(Al Cl3)∶n(亚茴香基丙酮)4∶1,n(环己烷)∶n(亚茴香基丙酮)4∶1的条件下反应稳定性较好,产物得率达95.1%。采用IR、GC-MS和1H NMR等分析技术对合成所得产物进行了表征。 相似文献
16.
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
17.
Cyclisation of farnesyl pyrophosphate into sesquiterpenoids in ginger rhizomes (Zingiber officinale)
Kumkum Rani 《Fitoterapia》1999,70(6):52
The atomic ratios (14C/3H) obtained in ar-curcumene, α-zingiberene, β-bisabolene obtained from the essential oil of rhizomes of Zingiber officinale which were fed with [2-14C, 2-3H2], [2-14C, 4R-3H1] and [2-14C, 5-3H2]mevalonic acid and [1-3H2]farnesylpyrophosphate (FPP) revealed that (a) (2E,6E)-isomer of FPP is isomerised to (2Z,6E)-isomer without loss of epimeric hydrogen that means without a redox process; (b) (2Z,6E)-FPP is cyclised to bisabolyl cation which is the penultimate precursor of α-zingiberene, ar-curcumene and β-bisabolene; and (c) two 1,2-hydrogen shifts take place during the formation of α-zingiberene whereas one 1,2 shift has been observed during the formation of ar-curcumene. 相似文献
18.
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
19.
A new furanoeremophilane, 1alpha-chloro-6beta-isobutyroxy-9-oxo-10beta-hydroxy-furanoeremophilane (1) was isolated from the root of Ligularia atroviolacea and identified mainly on the basis of detailed spectral analyses including X-ray. Moreover, five known furanoeremophilanes,1alpha-hydroxy-6beta-isobutyroxy-9-oxo-10beta-H-furanoeremophilane (2), 1alpha-hydroxy-6beta-isobutyroxy-9-oxo-10alpha-H-furanoeremophilane (3), 1alpha,10beta-dihydroxy-6beta-angeloyloxy-9-oxo-furanoeremophilane (4), furanoeremophil-3-en-15,6alpha-olide (5) and furanoeremophil-15beta,6alpha-olide (6) were isolated from the same source. 相似文献
20.
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