香樟树叶挥发油的化学成分研究

用同时蒸馏萃取法(SDE)和气相色谱-质谱连用技术(GC-MS)对香樟树叶挥发油成分进行了分离分析,共鉴定出98种化合物。其中主要成分为樟脑与β-芳樟醇(24.099%)、桉油醇(15.723%)、α-松油醇(11.204%)、石竹烯(4.957%)、蛇床-6-烯-4-醇(5.724%)、β-水芹烯(3.394%)等。     

蒙古蒿精油化学成分的研究Ⅰ.

本文报道用毛细管气相色谱法及毛细管色谱-质谱-计算机体系对蒙古蒿精油化学成分进行分离和鉴定.30个单萜和含氧单萜化合物为2-甲基丁烯-[2]、甲叉环戊烷、7,7-二甲基-3-次甲基-双环(3,1,1)庚烷、α-(艹守)烯、α-蒎烯、莰烯、1-辛烯辛醇-3、β-(艹守)烯、β-蒎烯、α-菲兰烯、冰片烯、对甲基异丙基苯、松油烯醇-[1]、蒿属酮、γ-松油烯、β-松油醇、3,7,7-三甲基-双环(3,1,1)-2-庚醇、α-松油烯、马鞭烯酮、里哪醇、异(艹守)酮、(艹守)酮、樟脑、异胡薄荷酮、异龙脑、松油烯醇-[4]、α-松油醇、香桃木烯醇、反香芹烯醇和顺香芹烯醇.     

异-α-姜黄烯及其衍生物的合成

姜科姜黄属是一个重要的药用植物群其根茎和块根分别称为姜黄和郁金。中医中药认为, 郁金具有行气, 纠瘀和通经等功效。动物药理试验表明, 姜科植物温郁金具有抗生育活性, 而其挥发油主要含有姜烯、α-姜黄烯和异-α-姜黄烯等倍半萜类化合物。本文合成了温郁金挥发油的另一个成分异-α-姜黄烯和其衍生物2-甲基-6-对甲苯基-2-庚醇、脱氢异-α-姜黄烯和2-甲基-6-对甲苯基-5-庚烯-2-醇。它们的化学结构得到确证。     

广西产湿地松松针挥发性成分的提取及分析

采用水蒸气蒸馏法提取湿地松针叶挥发油的油相部分,用乙醚萃取法提取蒸馏残液中的水溶性挥发性组分,利用气相色谱-质谱联用分析比较二者的化学成分。湿地松挥发油油相部分的得油率为0.277%,共分离出86个色谱峰,鉴定了其中的49种化合物,占总含量的92.12%,油相部分的主要成分有β-蒎烯（14.29%）、吉马烯（12.87%）、α-蒎烯（6.79%）、β-石竹烯（6.15%）、α-石竹烯（1.58%）;水溶性部分的得油率为0.0682%,鉴定了其中的6种化合物,占水溶性部分总量的60.72%,α-松油醇（24.61%）为水溶性部分的主要成分。由于增加了水溶部分精油的提取,湿地松松针挥发油总的产油率提高到0.3452%,提高率达24.62%。     

浙江艾蒿和野艾蒿挥发油成分分析研究

用GC/MS进行浙江野艾蒿和艾蒿挥发油成分分析.鉴定出野艾蒿31个化合物,占挥发油含量的83.27%.主要成分为:桉叶素(21.82%)、胡椒烯(10.48%)、β-石竹烯(8.86%)、樟脑(8.50%)、侧柏酮(7.28%).鉴定出艾蒿24种化合物,占挥发油含量的77.70%.主要成分为:异蒿属酮(37.01%)、桉叶素(12.81%)、异蒿属醇(9.30%)等.两种同属植物含有18种相同化合物.     

松油醇的分析及其生产工艺改进的研究

 应用气相 红外光谱(GC FTIR)和气相 质谱(GC MS)对合成松油醇及其杂质成分、原料松节油、合成过程中间体粗油(红油和黄油)和天然松油醇进行了分析研究,为判断松油醇产品中杂质产生的原因及改进生产工艺提供了依据。研究结果表明,松油醇中的杂质主要为长叶烯和石竹烯,是由原料松节油带入的。天然松油醇粗油中主要成分是1,8 桉叶素、反式 4 艹守醇、p 异丙烯基甲苯、顺式 4 艹守醇、芳樟醇、樟脑、龙脑、4 松油醇、α 松油醇和黄樟素。天然松油醇中β 松油醇和γ 松油醇含量不如合成松油醇中的含量高,以此可判断松油醇是天然的还是合成的。     

茵陈挥发油的超临界CO2萃取法与水蒸气蒸馏法提取的比较

采用超临界CO2萃取法与水蒸气蒸馏法从菌陈中提取挥发油，用GC－MS法测定其化学成分和相对含量，对两种提取方法所得的挥发油进行比较，水蒸气蒸馏法提取菌陈挥发油的产率为0．03％（w），主要成分为匙叶桉油烯醇、吉玛烯D、反式－石竹烯、2，4－戊二炔苯、β－金石欢烯等；超临界CO2萃取法提取的产率为0．15％(w)，主要成分为百里酚、β－红没药烯、2－异丙基－4－甲基－1－甲氧基苯、异百里酚、2－特丁基－4－（2，4，4－三甲基戊基）苯酚、β－杜松烯等。     

气相色谱-质谱联用法结合保留指数对高良姜挥发油成分的分析

采用气相色谱-质谱联用(GC-MS)法结合保留指数(RI)对高良姜水蒸气蒸馏法(SD)、超声波辅助溶剂提取法(UAE)和亚临界流体萃取法(SFE)所制备的挥发油进行分析,分别鉴定出51,46和60个挥发性组分,并通过峰面积归一化法确定各组分的相对含量。结果表明,高良姜挥发油的指标性成分1,8-桉叶素含量的大小顺序为SD法≈SFE法UAE法,UAE法虽耗时少、能耗低,但由于所用有机溶剂难去除,所得挥发油品质较差。SFE法可得到部分SD法无法得到的化合物,如2-羟基-1,8-桉叶素、二苯基庚烷类等。另外β-石竹烯、α-石竹烯、α-法尼烯、γ-杜松烯等高沸点组分比例,SFE法所得高于另两种方法;α-蒎烯、莰烯、β-蒎烯、柠檬烯、樟脑和α-松油醇等低沸点组分比例,SD法所得最高。同一批药材不同提取方法所得的挥发油成分大部分相似,但部分成分与组分比例因不同提取方法的原理存在差异,实际生产中可根据功效需求选择不同提取方法加以开发利用。     

雪香兰挥发油化学成分的研究

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。     

气相色谱-质谱法测定艾叶挥发油中化学成分

采用水蒸气蒸馏法提取艾叶的挥发油,用气相色谱-质谱法分离和鉴定挥发油成分,并用归一化法测定其相对含量。共分离出76个组分,鉴定出59种化合物。其含量占总挥发油组分峰面积的94.3%。贵州遵义产艾叶主要挥发油成分及其含量为1,8-桉叶油素(22.19%)、樟脑(10.39%)、绿花白千层醇(6.57%)、蒿醇(4.95%)、L-龙脑(4.88%)、α-松油烯(3.98%)、蒿酮(3.44%)、顺式桧烯水合物(3.36%)、4-松油醇(2.68%)、菊油环酮(2.51%)、β-崖柏酮(2.41%)、1-松油醇(2.32%)和丁香酚(2.26%)等。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

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%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

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.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

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.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

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.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

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.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

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.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

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.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

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.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.