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1.
侧柏叶中挥发性组分的酶提取及分析   总被引:1,自引:0,他引:1  
侧柏叶为柏科(Cupressaceae)植物侧柏Biota orientalis(L.)End l.的干燥嫩枝叶,侧柏别名扁柏、香柏、片柏、片松。常绿乔木,多为栽培,为我国特产[1]。侧柏叶气清香,味苦涩、微辛。具有凉血止血、清肺止咳功效,在临床上常用于治疗出血症、风湿痹痛、高血压、咳喘等,国内外学者对  相似文献   

2.
陈巍  杜淼  张若桦  卜显和 《结构化学》2002,21(3):277-279
1 INTRODUCTION A number of Pt complexes with monosulfoxide have been isolated and characterized[1]. It was indicated that the sulfoxide group trends to coordinate to soft metals (Pt, Pd, etc.) by its sulfur atom[2]. Pt(Ⅱ) trends to bond to disulfoxides in cis-mode and such complexes have potential antitumor activity[2]. However, only few examples of such complexes have been structurally characterized[3]. We will report herein the crystal structure of a new Pt(Ⅱ) complex with a disulf…  相似文献   

3.
程伟贤  古昆  任周阳  李聪 《有机化学》2004,24(Z1):331-332
迷迭香(Rosemarinus officinalis L.)原产地中海沿岸,属唇形科植物,是目前公认的具有较高抗氧化作用的一种植物[1].20世纪60年代末和70年代初先后由德国和日本科学家从迷迭香中分离出具有高效抗氧化能力的成分[2].中国科学院植物研究所于1981年成功地引种了迷迭香,通过CO2超临界萃取法从迷迭香的茎叶中萃取出了芳香油[3],提取出了食用抗氧化剂(Rosemary Antioxidant,简称Rao)[4].  相似文献   

4.
禹白芷为河南禹州及周边县市所产白芷(Angelica dahurica(Fisch.ex Hoffm.)Benth.et Hook.f.)的习称,为白芷的主流栽培品种之一,作为我国传统的中药,具有散风除湿、通窍止痛和消肿排脓的功效,主治感冒头疼、鼻塞、白带、疮疡肿痛等疾病[1].  相似文献   

5.
HormoneisaveryhoP0tatkindofbiol0glcalmolede,ltplaTharegulationro1einmetabelism.TheinterachoLofrareeothwithborm0nehasearelybeenreporteds0far[1'2J.lntheprerentwork,theinteraedonofrareearthwith3.5,3'-triiodothryor`ire(T.)wasstodiaibyusingNMRandPOtentiometrictitrationat37tandanionicstrenotofO'15mo1e/LNaC1,TheP0tenhometrictitrah0nwasperformedin1:1DMSO-H.O(vol1imeratio)usingthemethoddedndinprevi01ispeper[3].TheNMR8peaofsarnples(PH=4,to)wererecorded'onBrukerARX-4ooNMRSpeCtrometerusingT…  相似文献   

6.
山苍子油化学成分的气相色谱-质谱分析   总被引:3,自引:0,他引:3  
山苍子为樟科木姜子属植物山鸡椒Litsea cubeba(Lour.)Pers.,广布我国南部省区[1].山苍子具有温中散寒、行气止痛等功效,可用于胃寒呕逆、脘腹冷痛、寒疝腹痛、寒湿郁滞等[2].其鲜果实提取的挥发油(山苍子油)有特殊的清香气,具显著的抗菌、祛痰、抗心律失常等作用[1].山苍子油为香料工业的重要原料,也是合成紫罗兰酮的主要原料[3].为了充分利用这一资源,贵州省在紫云县建立了近万亩的山苍子种植基地,2000年秋季第一次挂果.我们用气相色谱-质谱对贵州省紫云县的山苍子油进行分析研究,以便了解紫云县山苍子的质量情况,为进一步合理开发黔产山苍子提供科学依据.  相似文献   

7.
藏药材长花党参的GC-MS分析   总被引:1,自引:0,他引:1  
藏药材长花党参(Codonopsis thalictrifolia Wall.)为桔梗科党参属植物,主产于西藏南部,锡金、尼泊尔等地也有分布,生长在海拔3 600~4 600 m的草地或灌丛中[1-2].作为传统藏药材,长花党参据考证为<晶珠本草>中记载的"陆得多吉"药材之白花种类,用于消炎散肿和治湿疹[2].  相似文献   

8.
西番莲中黄酮碳苷的串联质谱分析   总被引:1,自引:1,他引:0  
西番莲(Passiflora incarnate L.)为西番莲科西番莲属植物,主要生长在中南美、澳洲、南非及东南亚地区,在我国南方地区也有分布.西番莲提取物中的主要活性成分为黄酬碳苷,它们具有抗焦虑、镇静、防止药物上瘾等药效[1].  相似文献   

9.
1nl994,DiazandHerzgroup[1]isolatedthreeneu'farnesane-basedlactones1,2and3fromtllep1antGochnotioglutinosa(Don)donexHook.etArn.grot"ninAIgentina.WehavereportedthefirstS}fnthesisof(i)-2inearl}'articlel=1.Hereinxt'ett'ishtodescribethefirsttotalSynthesisof(I)-lstartingfromgeraniolasitsracemicform.Theq'l1theticrouteisdetailedinthefollouingscheme.Tlleaceb'lpr0lectedgeraniol(AldricI1Co.)x"asconvertedtotheenal5usingSeO2/I-BuOOH9'steminrcfluxi11get11}'lalc0l10lI4].Tl1cli[lli1l111cnolatett'asge1…  相似文献   

10.
1INTRODUCTION Crystal engineering has captured the interest of re-searchers these years[1,2].Especially,supramolecular chemistry based on weak interactions(hydrogen bond,π-πstacking,C–H···O interaction,ion-πinter-action and hydrophobic interaction,et al.)is one of the most hottest studying fields[3~5].So far,in this field,intensive endeavors have been paid to the synthesis of novel functional complexes possessing catalysis,non-linear optical property,magnetism and molecular recog…  相似文献   

11.
利用手持技术改进测定乙醇分子结构实验   总被引:1,自引:0,他引:1  
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。  相似文献   

12.
13.
由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。  相似文献   

14.
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989.  相似文献   

15.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

16.
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988.  相似文献   

17.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

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18.
实验教学目的是从解决实际问题出发,以实验技术训练和实验设计思想培养为目标。介绍了将单一的物质分配系数测定实验改进为综合实验,提高了实验效果及实验资源利用率。  相似文献   

19.
Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases.  相似文献   

20.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

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