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1.
Four new sesquiterpenoids, 1,4-trans-6-hydroxyisocalamenene; 1,4-trans-6-methoxyisocalamenene; (+)-aristol-9-en- 12β-ol, and eudesm-4(15)-en-6β-acetoxy-7β-ol, were isolated from Bazzania tridens, a liverwort species. Their structures were identified by means of spectroscopic methods. The two isocalamenenes are derived from a methyl rearrangement of the calamenene skeleton.  相似文献   

2.
The sesquiterpene aldehyde, tridensenal, of previously unknown skeleton was isolated from the Taiwanese liverwort Bazzania tridens. The structure of tridensenal was elucidated on the basis of spectral data and proved by synthesis of the diastereomeric mixture.  相似文献   

3.
南海海绵Pseudoceratina purpurea活性成分的研究(Ⅰ)   总被引:1,自引:0,他引:1  
从中国南海海绵Pseudoceratina purpurea的乙酸乙酯萃取部分提纯 出两个化合物,应用IR,1H-NMR,MS等波谱技术确定它们为正十六酸和 3-β-5-烯-谷甾醇。  相似文献   

4.
Sixteen compounds, (+)-ushinsunine-β-N-oxide ( 1 ), cleistopholine ( 2 ), liriodenine ( 3 ), (-)-anonaine ( 4 ), (+)-nornuciferine ( 5 ), (+)-N-acetylnornuciferine ( 6 ), (-)-ushinsunine ( 7 ), (-)-norushinsunine ( 8 ), (-)-asimilobine ( 9 ), (+)-reticuline ( 10 ), N-trans-feruloyltyramine ( 11 ), β-sitosterol (12) and stigmasterol ( 13 ), lyscamine ( 14 ), (-)-anaxagoreine ( 15 ) and trans-cinnamic acid ( 16 ) were isolated from the methanolic extract of the Cananga odorata. Among them, 1 is a new stereoisomer of ushinsunine-β-N-oxide. The structures of these compounds were established by means of spectral experiments.  相似文献   

5.
宽叶秦岭藤根部的化学成分   总被引:6,自引:0,他引:6  
通过正相和反相硅胶柱层析从宽叶秦岭藤根部乙醇提取物中分离纯化得到19个化合物,经波谱分析并结合化学方法鉴定了其结构,其中4个为新化合物,它们分别是3,5-二羟基二十烷酸羽扇豆醇酯(3),2-羟甲基-5-甲氧基苯基-O-β-D-吡喃葡萄糖甙(11),Δ5-孕甾烯-3β,20(S)-二醇-20-O-β-D-吡喃葡萄糖基(1→6)-β-D-吡喃葡萄糖甙(18,秦岭藤甙C)和Δ5-孕甾烯-3β,20(S)-二醇-3-O-β-D-吡喃葡萄糖基-20-O-β-D-吡喃葡萄糖基(1→6)-β-D-吡喃葡萄糖甙(19,秦岭藤甙D).  相似文献   

6.
中国马先蒿化学成分研究   总被引:1,自引:0,他引:1  
中国马先蒿化学成分研究王长增,贾忠建(兰州大学有机化学研究所,应用有机化学国家重点实验室,兰州,730000)关键词中国马先蒿,玄参科,环烯醚萜,NOE差谱,二维核磁中国马先蒿(Pedicularischinensis)系玄参科马先蒿属植物。本文报道...  相似文献   

7.
Three new steroids named as shuilongguine I ( 1 ), shuilongguine II ( 2 ) and shuilongguine III ( 3 ), together with eleven known compounds were isolated from Polypodium niponicum (Chinese name “Shuilonggu”, Berberidaceae). Their structures were deduced by spectroscopic methods and 2D NMR experiments.  相似文献   

8.
Nineteen compounds were isolated from the CHCl3 soluble portion of the heartwood of Eucalyptus citriodora. These compounds included trans‐calamenene (1), T‐muurolol (2), α‐cadinol (3), 2β‐hydroxy‐α‐cadinol (4), 4‐hydroxy‐3,5‐dimethoxybenzaldehyde (5), 4‐hydroxy‐3,5‐dimethoxybenzoic acid (6), linoleic acid (7), squalene (8), α‐tocopherol (9), erythrodiol (10), morolic acid (11), betulonic acid (12), cycloeucalenol (13), cycloeucalenol vernolitate (14), β‐sitosterol (15), β‐sitosteryl‐β‐D‐glucopyranoside (16), β‐sitostenone (17), yangambin (18), sesamin (19). Among them, 14 is a new compound. The structures of these compounds were elucidated on the basis of spectroscopic evidence.  相似文献   

9.
After the geometry optimization at B3LYP/6-31+G(d,p) level,the NMR calcula-tions of a series of fluorenone analogues have been carried out by GIAO method at HF/6-31+G(d) level and B3LYP/6-311G+(2d,p) level,respectively.The 13C NMR chemical shifts calculated at HF/6-31+G(d) level show better agreement with the observed values.By a series of linear correction equations (δpred=a + bδcalc),accurate prediction of 13C chemical shifts was achieved for the new fluorenone compound.The linear correlation of δpred with δexptl is excellent,and the square of correlation coefficient,r2,is up to 0.994.The maximum absolute difference between δpred and δexptl,Δδ,is 4.6 ppm,and the root-mean-square error between δpred and δexptl is only 2.6 ppm.  相似文献   

10.
Seven kinds of flavones, β-sitosterol, β-sitosterol-D-glucoside, hesperidin, limonin, ferulic acid and succinic acid were isolated from the fruit peel of Citrus tankan Hayata.  相似文献   

11.
The chemical structure and stereochemistry of 12 intermediates in the total synthesis of (+)‐biotin starting from D ‐mannose as chiral pool were completely assigned using one‐ and two‐dimensional NMR experiments, including 1D selective NOE, DEPT, COSY, HSQC and HMBC. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

12.
From the hexane and acetone extractive of the wood of Keteleeria davidiana Beissner, α-pinene, β-pinene, limonene, α-copaene, bornyl acetate, β-elemene, caryophyllene, caryophyllene oxide, α-selinene, β~selinene, selin-11-en-4α-o1, laevojunenol, α-cyperone, stigmasterol, β-sitosterol, tetracosyltetracosanoate, docosanyl tetracosanoate, hexacosanyltetracosanoate, tetracosanol, hexacosanol, docosanol, α-conidendrin and 15-hydroxydehydroabietic acid were isolated. Straight chain saturated hydrocarbons (C13, C14, C17-C14) were also obtained.  相似文献   

13.
Eleven chemical constituents were isolated from the ethyl acetate soluble fraction of the aerial part of Rosa laevigata Michx. These compounds include the Henze's ketol (16), diethyl malate (17), three γ-lactones (18-20), loliolide (21), p-coumaric acid (22), 6,7-dimethoxycoumarin (23) and three flavonoids (24-26). The new compounds 19 and 20 were determined to be the cis- and trans-isomers of ethyl 2-benzyl-3-hydroxy-5-oxo-3-furancarboxylate.  相似文献   

14.
电化学石英晶体阻抗系统;疏基乙酸;溶菌酶在裸金电极和疏基乙酸或正十二疏烷基醇修饰电极上的吸附  相似文献   

15.
远东疣柄牛肝菌的化学成分   总被引:3,自引:0,他引:3  
从远东疣柄牛肝菌(Leccinum extremiorientale)子实体中提取分离得到13个 化合物,通过理化常数和波谱数据分析,它们的结构被鉴定为:麦角甾-7,22-二 烯-3β,5α,6β-三醇(1),麦角甾醇过氧化物(2),麦角甾醇(3),麦角甾 -4,6,8(14),22-四烯-3-酮(4),麦角甾-5,7-二烯-3β-醇(5),棕榈酸 (6),(2S,3S,4R,2’R)-2-(2’-羟基二十四碳酰胺)十八烷-1,3,4-三 醇(7),脑苷脂B(8),脑苷脂D(9),尿嘧啶(10),肌苷(11),腺苷(12 ),D-阿洛醇(13),利用2D NMR(~1H-~1H COSY,HMBC,HMQC)技术首次对化合 物8和9的氢谱和碳谱数据进行了全归属。在浓度为100 μg/mL时,化合物2,7和8 表现出选择性地抗蛇毒Crotalus adamenteus分泌的磷脂酶A_2活性,而对蜂毒 Apis mellifcra磷脂酶A_2却无活性。此外,远东疣柄牛肝菌提取物对粘虫拒食率 和小莱蛾死亡率分别为67%和55%。  相似文献   

16.
Three new natural products, the taraxastane‐type triterpenoid 1 , the azafluorene‐based constituent 2‐hydroxyonychine ( 2 ), and the diterpenoid nemoralisin ( 3 ) were isolated from the EtOH extract of Polyalthia nemoralis, along with five known compounds. The structures of the new compounds were established by in‐depth spectroscopic and mass‐spectrometric analyses, as well as by chemical transformation.  相似文献   

17.
A novel nortriterpene, acanthochlamic acid (6), along with 18 known compounds has been isolated from the whole plants of Acanthochlamys bracteata P. C. Kao, a single species in family Acanthochlamydaceae which is endemic to the southwest of China. The structure of the novel nortriterpene was elucidated as 3,4-seco-3-norlup-4(23),20(29)-dien-2,28-dioic acid by spectroscopic techniques including 1D and 2D NMR spectroscopy and confirmed by X-ray crystallography.  相似文献   

18.
锥疣星蔓蛇尾的化学成分   总被引:1,自引:0,他引:1  
报道锥疣星蔓蛇尾(Axtroclarus coniferus)的次生代谢物及其生理活性,从采自于广西涠洲岛的锥疣星蔓蛇尾分离得到4种甾类化合物,利用波谱方法确定出它们的结构为胆甾-5(6)-烯-3β-硫酸酯钠(1)、3,5-胆甾二烯(2)、24-乙基胆甾醇(3)、麦角甾醇(4),化合物1具有显著的抗肿瘤活性。  相似文献   

19.
川明参茎叶中的化学成分   总被引:6,自引:0,他引:6  
川明参 ( Chuanminshen violaceum Sheh et Shan)属于伞形科川明参属 ,在形态上与明党参相近 ,是我国特有的单种属植物 ,主要分布在四川 ,多为栽培 [1] .其根作为滋补药材 ,具有润肺化痰、和胃生津和解毒等功效 .饶高雄 [2 ] 及周燕等 [3] 曾对不同产地的川明参根部化学成分进行了研究 ,分离鉴定出的主要成分为芦丁和多种香豆素 .为了进一步探索川明参的活性成分以及对川明参资源的综合开发利用 ,我们对一般弃置不用的川明参茎叶的化学成分进行了研究 ,从其水煮提取物中分离得到 8个化合物 ,通过波谱分析鉴定了其中 7个化合物 ,它们是 4-…  相似文献   

20.
Bioassay‐guided fractionation of an AcOEt‐soluble fraction of the liquid fermentation of an endophytic fungus Hypoxylon sp. BCRC 12F0687 associated with the root of Taiwanese Ilex formosana (Aquifoliaceae) resulted in the isolation of two new compounds, i.e., one benzenoid, hypoxyphenone ( 1 ), and one azaphilone derivative, hypoillexidiol ( 2 ), two metabolites isolated for the first time from natural source, (?)‐(3S)‐3‐hydroxy‐3‐methyloxindole ( 3 ) and (+)‐vermelone ( 4 ), along with twelve previously identified compounds, 5 – 16 . Their structures were determined through in‐depth spectroscopic and mass‐spectrometric analyses. The effects of some isolates on the inhibition of NO and IL‐6 production in lipopolysaccharide‐activated RAW 264.7 murine macrophages were evaluated. Of the isolates, 2 and 3 exhibited potent anti‐NO production activity, with IC50 values of 17.5±1.8 and 24.7±1.6 μM , respectively, compared to that of quercetin, an iNOS inhibitor with an IC50 value of 35.9±1.7 μM . Compounds 2, 4, 5 , and 12 also showed moderate inhibition of IL‐6 production, with IC50 values ranging from 27.2±1.8 to 35.3±5.8 μM . This is the first report on an oxindole metabolite from the genus Hypoxylon.  相似文献   

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