首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 109 毫秒
1.
利用静态顶空-毛细管气相色谱-质谱方法对复方祛风湿止痛药中挥发性成分进行了分析,运用质谱检索和保留指数对其中主要的60种挥发性成分进行了定性.该药中各种挥发性成分的相对含量分别为萜类(54.5%)、萜类衍生物(9.6%)、酚醚类(15.0%)和脂肪醇醛(8.5%),主要为β-古芸烯(20.5%)、蒿脑(14.5%)、β-蛇床烯(6.0%)和β-绿叶烯(5.7%).分析结果的相对标准偏差(RSD)在0.54%~8.39%之间.  相似文献   

2.
气相色谱-质谱技术分析红松松塔挥发性成分   总被引:8,自引:0,他引:8  
采用水蒸气蒸馏法,对红松松塔挥发性成分进行提取和研究,最佳蒸馏时间5.5h,挥发油提取率1.28%。利用气相色谱-质谱联用技术对提取的挥发油成分进行分析,共鉴定出32种化学成分,主要为单萜和倍半萜类化合物,其中相对含量较高的有α-蒎烯(44.258%)、D-柠檬烯(23.426%)、β-蒎烯(8.674%)、有石竹烯(3.462%)、β-月桂烯(3.018%)等。研究结果表明红松松塔挥发油中富含α-蒎烯、D-柠檬烯、石竹烯等多种具有药理活性的成分。因此,红松松塔是一种具有较好前景的天然药用资源。  相似文献   

3.
固相微萃取-气相色谱/质谱法分析白胡椒粉的风味成分   总被引:1,自引:0,他引:1  
采用固相微萃取采集白胡椒粉的挥发性成分,用色谱/质谱法分析鉴定,并用总离子流色谱峰的峰面积进行归一化定量分析其风味成分,鉴定出石竹烯(20.88%),1-甲氧基-4-(2-丙烯基)苯(20.57%),β-水芹烯(15.27%),3-蒈烯(14.56%),1-甲基-3-异丙基苯(3.62%),β-蒎烯(2.69%),芳樟醇(2.69%),香叶烯(2.36%),墨榄香烯(2.10%),胡椒烯(1.32%)等48种化合物。  相似文献   

4.
采用固相微萃取-气相色谱-质谱法分离和鉴定香樟籽的挥发性成分,用归一化法测定其相对含量。共分离出76种组分,鉴定出47种化合物,其含量占总挥发性成分的97.4%。主要挥发成分为樟脑(57.89%)、柠檬烯(12.68%)、α-蒎烯(4.42%)、莰烯(2.69%)、香橙烯(2.34%)、伞花烃(2.26%)及β-蒎烯(2.12%)。  相似文献   

5.
毛樱桃叶片挥发油成分GC-MS分析   总被引:1,自引:0,他引:1  
采用GC—MS技术,分析了毛樱桃叶片中的挥发性成分.气相色谱共检测出163个峰,经与质谱标准图谱比较,鉴定了其中15种化学成分,其中含量较高的为棕榈酸酐、12E-11-甲基乙酸十四烯酯和十四酸甲基乙酯(相对百分含量分别为25.104%,4.873%和2.811%).  相似文献   

6.
采用动态顶空吸附/手性毛细管气相色潜-质谱(GC—MS)法,首次分析研究了马尾松(Pinus massoniana Lamb)、湿地松(Pinus elliottii Engelm)、油松(Pinus tabulaeformis Carr.)针叶挥发性化合物中主要手性单萜(α-蒎烯、莰烯、β-蒎烯、β-水芹烯、柠檬烯)的组成与相对含量,结果表明其在种间相差较大。马尾松中的(-)-α-蒎烯的含量(55.50%)最高,而其对映异构体(+)-α/-蒎烯在油松中含量(16.86%)最高,(-)β-蒎烯在湿地松中含量(43.38%)最高。马尾松手性单萜的组成和含量在树与树间差异也较大。  相似文献   

7.
气相色谱-质谱法分析蘘荷花穗挥发油化学成分   总被引:3,自引:0,他引:3  
采用水蒸气蒸馏法提取黔产蘘荷花穗挥发油,并用气相色谱-质谱对其成分进行定性分析和峰面积相对含量的测定.共鉴定出45个化学成分,占挥发油总量的95.89%.主要成分为β-水芹烯(34.96%)、α-律草烯(13.09%)、β-榄香烯(7.31%)、β-蒎烯(6.50%)、α-水芹烯(6.07%)、α-蒎烯(3.87%)、β-石竹烯(3.18%)等。  相似文献   

8.
采用水蒸汽蒸馏法从雪香兰中提取挥发油,利用GC—Ms联用仅对其化学成分进行分析,用归一化法计算各组分的相对百分含量。经毛细管气相色谱分离出33个峰,共确认了其中31种成分,占总油量的98%。其主要成分是斯巴醇、α-石竹烯、1-乙烯基-1-甲基-2-(1-甲基乙烯基)4-(1-甲基二乙烯基)-环己烷、3,7,11-三甲基.1,6,10-十二碳三烯-3-醇等。  相似文献   

9.
采用顶空-气相色谱-四极质谱法和顶空-气相色谱-飞行时间质谱法对鱼腥草挥发性成分进行检测,运用保留指数结合准确质量测定,分别从鱼腥草茎和叶中鉴定出49、39种挥发性组分,并采用峰面积归一化法测定各组分的相对含量。鱼腥草茎和叶中的挥发性成分差别较大。鱼腥草茎以α-蒎烯(12.24%)、β-蒎烯(22.42%)、月桂烯(11.98%)、乙酸冰片酯(10.97%)、甲基正壬酮(10.83%)为主要成分,而鱼腥草叶则以月桂烯(39.48%)、(Z)-β-罗勒烯(26.52%)、癸醛(10.35%)、桧烯(4.43%)、甲基正壬酮(2.44%)为主。结合保留指数和准确质量测定能显著提高质谱定性的准确性,有利于解决质谱检索时定性不确定的问题。  相似文献   

10.
固相微萃取-气相色谱-质谱分析牡丹花的挥发性成分   总被引:4,自引:0,他引:4  
用固相微萃取装置(SPME)顶空提取牡丹花的挥发性成分,采用气相色谱-质谱(GC-MS)联用技术定性分析不同品种牡丹花的挥发性成分,归一法计算其相对百分含量,同时对SPME与水气蒸馏提取效果进行了比较。10个品种牡丹花共检出34种成分,其中多数是烷烃。不同品种牡丹花的成分与相对百分含量不同,少量的醇、酯、烯等成为其特有成分。  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

13.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

14.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

15.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

16.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

17.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

18.
19.
《Tetrahedron》2014,70(21):3377-3384
The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.  相似文献   

20.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号