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1.
新香茶菜素的结构 总被引:1,自引:0,他引:1
从河南大别山地区产显脉叶香茶菜[Rabdosia nervosa(Hemsl.)C.Y.Wu et H.W.Li]叶的乙醚提取物中分离到三个二萜化合物,其中 odonicin 和显脉香茶菜素(nervosin)已报道,本文报道另一个新化合物,命名为新香茶菜素(neorabdosin,1)的结构研究.1为无色针状结晶,有微弱芳香气味,熔点230~232℃,[α]_D~(13)-175.5°(c 0.86,吡啶).经元素分析和质谱测定,其分子式为 C_(24)H_(30)O_7,M_r=430.48.IR:1735,1220(乙酰基),1720(六 相似文献
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三种西藏香茶菜挥发油化学成分的研究 总被引:4,自引:1,他引:4
唇形科植物香茶菜广泛分布于全国各地,民间一直用作抗菌消炎药使用,近年来发现,香茶菜属植物有抑制肿瘤和抗癌活性,其活性成分是二萜。我们对采自西藏的3种香茶菜的挥发油进行了GC/MS分析。从小叶香茶菜[Rabdosia Parrifolia(Batal)Hara; Litte leaf Rabdosia]油中分出84个峰,鉴定了27个,占总面积的60%;从川藏香茶菜(Rabbosia Pseudo-irrarata C.Y.Wu,Szechwan-Tibet Rabdosia)油中分出72个峰,鉴定了39个,占总面积的82.5%;从皱叶香茶菜[Rabdosia rugosa(Wcll.)Hara,Wrinkted leaf Rabdosia]中分出了90个峰,鉴定了39个,占总面积的62.1%。3种香茶菜的分析尚未见报道。 相似文献
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从采自西藏的皱叶香茶菜中分离鉴定了3对B-闭联对映贝壳杉烯型二萜化合物:二萜化合物皱叶香茶菜素(Ⅰ)和二氢皱叶香茶菜素(Ⅱ);isodocarpin(Ⅲ)和dihydroisodocarpin(Ⅳ)及Carpalasionin(Ⅴ)和dihydrocarpalasionin(Ⅵ)。(Ⅰ)、(Ⅲ)和(Ⅴ)分别与对应的二氢化合物(Ⅱ)、(Ⅳ)和(Ⅵ)以混合物的形式被分离和鉴定。化合物(Ⅱ)为新化合物,(Ⅰ)、(Ⅳ)和(Ⅵ)首次在自然界发现,(Ⅲ)和(Ⅴ)为已知化合物。 相似文献
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报道从大萼香茶菜叶的乙醇提取物中分离得到一种新的二萜类化合物, 并命名为大萼香茶菜癸素(1). 其药理活性实验结果证明, 该化合物对体外培养的Hela细胞有较强的抑制作用. 相似文献
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香茶菜属二萜类化合物的1H NMR 研究 总被引:1,自引:0,他引:1
通过对二十三个香茶菜植物中二萜类化合物的1HNMR 参数的归纳, 总结了这些化合物的主要质子信号的规律, 用分子模型使分子立体结构(B,C 环构象和取代基构型)与峰形相关连, 为此类化合物的签别和结构确定提供了依据. 相似文献
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采用二维核磁共振波谱完全归属了天然有机化合物香茶菜醛的~1H和~(13)C NMR化学位移,测定了部分质子的偶合常数,并用孤立自旋对近似方法定量处理香茶菜醛的相敏NOESY谱,根据1/r_(ij)~8∝A_(ij)计算出相应的质子间距离.其溶液中的三维空间结构采用以NMR结构参数为初始数据的WUPH计算程序和分子力学能量优化(MM2)完成计算.计算结果表明,得到的香茶菜醛在溶液中的三维空间结构反映了该化合物在溶液中的真实空间结构. 相似文献
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Hydroxylated uroporphyrin I and urochlorin I derivatives formed by photochemical oxidation of uroporphyrinogen I were separated by high-performance liquid chromatography and fully characterized by electrospray ionization tandem mass spectrometry. The porphyrins and chlorins were identified by analysis of their product ion spectra with each hydroxylated derivative giving a characteristic collision-induced dissociation fragmentation pattern. The porphyrins and chlorins characterized were meso-hydroxyuroporphyrin I, alpha-hydroxypropionic acid uroporphyrin I, beta-hydroxypropionic acid uroporphyrin I, hydroxyacetic acid uroporphyrin I, trans-7-hydroxy-8-spirolactoneurochlorin I, cis-7-hydroxy-8-spirolactoneurochlorin I and trans- and cis-7,8-dihydroxyurochlorins I. 相似文献
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Anthony A. Shaw Larry A. Wainschel Martin D. Shetlar 《Photochemistry and photobiology》1992,55(5):647-656
We have studied the photoreactions occurring when p-aminobenzoic acid (PABA), a component of some sunscreens, is irradiated in aqueous solution. These studies were carried out in the presence and absence of oxygen, using light of lambda = 254 nm as well as light of wavelengths greater than 290 nm. In deoxygenated solution between pH 7.5 and 11.0, we found two photoproducts that were identified as 4-(4'-aminophenyl)aminobenzoic acid (I) and 4-(2'-amino-5'-carboxyphenyl)aminobenzoic acid (V); we used 1H and 13C NMR, electron impact mass spectrometry and synthesis by an independent route to identify each of these compounds. Rapid discoloration of the photolyzed sample was observed when PABA was irradiated in aerated solution. Although a number of products were detected under these conditions, the three most abundant stable compounds have been isolated and identified as 4-amino-3-hydroxybenzoic acid, 4-aminophenol and 4-(4'-hydroxyphenyl)aminobenzoic acid (IV). The latter compound was shown to result from rapid photo-induced oxidation of I in the presence of oxygen. Even in the presence of trace amounts of oxygen, the yield of I was significantly reduced in favor of IV. Studies of the thermal oxidation of I, coupled with evidence gathered from studies of the photochemistry of incompletely deoxygenated PABA solutions, indicate that 4-(2,5-cyclohexadien-4-one)iminobenzoic acid (III) is an intermediate on the pathway between I and IV. Qualitatively, we found that the photochemical reactions resulting from irradiation of PABA solutions with lambda = 254 nm light and light with lambda greater than 290 nm were the same. The quantum yields for formation of I and V are highly pH dependent, both being less than 10(-4) at pH 7 and rising steadily to values greater than 10(-3) at pH 11. The detailed pH dependence suggests that the deprotonated PABA radical cation may be an important intermediate entering into the reactions forming I and IV. 相似文献
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R. Sanduja G. E. Martin A. J. Weinheimer M. Alam M. B. Hossain Dick van der Helm 《Journal of heterocyclic chemistry》1984,21(3):845-848
The marine coelenterate Echinopora lamellosa (class Anthozoa, family Scleractinidae) was found to contain a number of unprecedented secondary metabolites which were isolated and identified as smilagenin (I), neodunol methyl ether (II), glycyrrhetic acid (III), 3β-acetoxyglycyrrhetic acid (IV), and 3β-acetoxy-11-deoxoglycyrrhetic acid (V). The structure of neodunol methyl ether was confirmed and its absolute configuration determined by the x-ray diffraction method. 相似文献
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Fatima N Tapondjou LA Lontsi D Sondengam BL Atta-Ur-Rahman Choudhary MI 《Natural product letters》2002,16(6):389-393
Phytochemical investigations on the non-alkaloidal extracts of Mitragyna stipulosa bark has led to the isolation of a series of triterpenoids mainly consisting of quinovic acid ([structure: see text]) and its glycoside derivatives [structure: see text] and [structure: see text]. The other constituents isolated include alpha-amyrin, 3beta-acetyl ursolic acid and a mixture of oleanolic and ursolic acid and beta-sitosterol glucopyranoside. Their structures were identified by spectral and chemical studies and compounds [structure: see text] and [structure: see text] were, respectively, identified as quinovic acid 3-O-[beta-D-glucopyranoside] (quinovin glycoside C) and quinovic acid 3-O-[beta-D-quinovopyranoside]-27-O-[beta-D-glucopyranosyl] ester. Compounds [structure: see text] and [structure: see text] showed significant inhibitory activity against snake venom phosphodiesterase I. 相似文献
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The UV light irradiation of isoniazid (I) in methanol four products, isonicotinic acid (II), isonicotinamide (III), N, N′-bis(isonicotinic acid)hydrazide (IV) and isonicotinaldehyde isonicotinyl hydrazone (V), in ethanol three products, (III), (IV) and acetaldehyde isonicotinyl hydrazone (VI) were isolated and identified. Also, the photoreaction mechanism of isoniazid in methanol and ethanol were discussed. 相似文献
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Linolenic acid hydroperoxide, enzymatically produced by soybean lipoxygenase from linolenic acid, was purified by high-performance liquid chromatography (HPLC) using a Supelco LC-8 (5 microns), 22 cm X 4.6 mm I.D. column with a solvent system of acetonitrile-tetrahydrofuran-0.1% phosphoric acid (50.4:21.6:28, v/v/v). The hydroperoxide was converted to several derivatives, the hydroxy, methyl, and stearate which were analyzed by HPLC and identified by gas chromatography-mass spectrometry. The 13-hydroperoxy linolenic acid was the major hydroperoxide produced by soybean lipoxygenase. 相似文献
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神农架地区五味子科植物成分的研究 I: 铁箍散茎和根的化学成分研究 总被引:1,自引:0,他引:1
用铁箍散的茎和根中分得六个化合物, 其中一个是新化合物, 命名为表恩施辛(1,epienshicine), 在体外具有抗癌活性. 其结构由光谱分析和化学转化确定为1-氧代-2R, 3S-二甲基-4R-(3-甲氧基-4-羟基苯)-6,7-次甲二氧基四氢萘. 其余五个为已知物, 分别鉴定为恩施辛(2,enshicine),isoschizandrolic acid(3), 去氧五味子素, β-谷甾醇和硬脂酸, 其中3系首次自天然界获得. 相似文献
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IntroductionThereisconsiderableteclndcalinterestillcyallilledyeswitllabsorptionInakilnaintilenear-infraredregion,principallybecauseoftheirpotelltialapplicationinareassuchaslaserandopticaldaisstorageteclmology'.However,tileligllifastnesspropertiesofcyaninedyesarenotasgoodasUloseoftileoillerdyes,i.e.Uleyareeasilypllotooxidized.Therefore,itisverysignificanttostudytilepllotooxidationofcyaninedyes.WehavepreviouslyreportedaseriesofstudiesOilhlepllotofadingofsomefunctionalcyaninedyes'.'.RecentstUd… 相似文献
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V. I. Akhmedzhanova I. A. Bessonova S. Yu. Yunusov 《Chemistry of Natural Compounds》1980,16(6):574-576
The alkaloids skimmianine, dubinidine, foliosidine, graveoline, and compounds (I) and (II) have been isolated from the epigeal part of the plantHaplophyllum foliosum Vved. (family Rutaceae). On the basis of the spectral characteristics of (I) and its 0-isopropylidene derivative it has been established that the compound is the alkaloid edulinine. Substance (II) was identified as ferulic acid by direct comparison with an authentic sample. This is the first time that edulinine and ferulic acid have been detected in plants of the genusHaplophyllum. 相似文献