香丹注射液中丹酚酸B的HPLC法测定

建立了1种测定香丹注射液中丹酚酸B含量的反相高效液相色谱法;色谱分析柱为Hypersil ODS(4.6mm×250 mm,5μm),流动相为甲醇-乙腈-甲酸-水(体积比27∶9∶1.1∶62.9,含10 mmol/L的四丁基溴化铵),检测波长为285 nm,流速为1.0 mL/min,柱温为31℃时,丹酚酸B得到较好的分离;丹酚酸B进样量在0.264~1.584μg范围内线性良好,r=0.999 8,方法平均回收率为98%,为香丹注射液质量控制提供了分析方法。     

UPLC法同时测定注射用丹参(冻干)中6种酚酸的含量

建立同时测定注射用丹参(冻干)中丹参素钠、原儿茶酸、原儿茶醛、异阿魏酸、丹酚酸G和迷迭香酸6种酚酸类成分含量的UPLC法。采用ACQUITY UPLCHSS T3(2.1 mm×100 mm,1.8μm)色谱柱,流动相为0.1%甲酸(A)-乙腈(B)系统梯度洗脱(0 min,100%A;0~5 min,0%B~8%B;5~10 min,8%B~20 B;10~20 min,20%B~45%B;20~24 min,45%B~100%B;24~25 min,100%B~100%A;25~30 min,100%A),流速0.3 mL/min,柱温30℃,检测波长254 nm。结果显示6种酚酸类成分在一定范围内(丹参素钠101.5~1624.0μg/mL、原儿茶酸0.846~13.540μg/mL、原儿茶醛82.60~1321.60μg/mL、异阿魏酸5.01~80.16μg/mL、丹酚酸G 8.97~143.52μg/mL、迷迭香酸8.67~138.72μg/mL)线性关系良好(r=0.9990~0.9998),平均加样回收率在95.1%~102.9%范围内,RSD均小于3.0%。该法经验证准确可靠,可用于该制剂中6种酚酸的含量测定,为其多成分质量控制提供了科学依据。     

HPLC/MS测定蒲公英颗粒中绿原酸、咖啡酸和阿魏酸的含量

建立了同时测定蒲公英颗粒中绿原酸、咖啡酸和阿魏酸3种酚酸物质含量的HPLC-MS方法.样品用含5%甲酸的甲醇溶液超声提取后,在Zorbax Eclipse XDB-C18(2.1mm×150mm,5μm)色谱柱上,以含0.2%甲酸的水(A)-乙腈(B)体系为流动相,进行梯度洗脱,线性梯度洗脱程序为:Omin,5%B;1.5min,10%B;10min,40%B;流速:0.25mL/min;在ESI正离子模式下,采用选择性离子监测方法进行检测.结果显示,绿原酸、咖啡酸和阿魏酸的线性范围分别为0.050～20.0、0.030～20.0和0.100～20.0μg/mL,检出限分别为0.010、0.006和0.020μg/mL.平均加标回收率为96.4%～101.6%,相对标准偏差为1.7%～3.3%.样品在10 h内测定基本不变,可用于蒲公英颗粒的质量控制.     

吹扫捕集-气相色谱-质谱法测定土壤中乙酸乙酯和丙烯酸乙酯

建立吹扫捕集-气相色谱-质谱法测定土壤中乙酸乙酯和丙烯酸乙酯的方法。称量5 g土壤样品于40 mL吹扫瓶中,加入5 mL超纯水进行吹扫捕集提取,用DB-624毛细管色谱柱（60 m×250μm,1.4μm）分离,全扫描后进行谱库检索定性,内标法定量。乙酸乙酯和丙烯酸乙酯的质量浓度在5.0～200μg/L范围内与定量离子与内标定量离子色谱峰面积的比值线性关系良好,相关系数分别为0.999 6和0.999 2,检出限分别为1.2、1.4μg/kg。样品加标平均回收率分别为95.8%～108%,79.9%～98.0%,测定结果的相对标准偏差分别为1.92%～13.7%、2.05%～13.8%(n=6)。该方法可用于土壤中乙酸乙酯和丙烯酸乙酯的测定。     

超高效液相色谱-蒸发光散射检测法同时测定重楼消瘤方中5种皂苷类成分含量

建立了同时测定抗肿瘤中药复方——重楼消瘤方中重楼皂苷Ⅰ、重楼皂苷Ⅱ、重楼皂苷Ⅶ、柴胡皂苷a、柴胡皂苷d 5种皂苷类成分含量的超高效液相色谱-蒸发光散射检测(UPLC-ELSD)法。复方制剂经甲醇提取,采用Waters Cortecs UPLC C₁₈(150 mm×2.1 mm,1.6μm)色谱柱分离,乙腈-水为流动相进行梯度洗脱,蒸发光散射检测器进行检测,以外标法定量。结果显示,5种皂苷类成分的分离度良好,分别在7.1174～177.94μg/mL、 9.4072～235.18μg/mL、 8.8726～221.82μg/mL、 7.4862～187.15μg/mL、9.761 3～244.03μg/mL范围内线性关系良好,相关系数(r)为0.999 2～0.999 8,检出限为0.7～1.0μg/mL,定量下限为1.8～2.4μg/mL;平均回收率分别为93.9%、103%、102%、104%、105%,相对标准偏差(RSD)分别为3.8%、4.0%、4.2%、3.6%、3.2%。该方法简便、快速、准确,可同时对重楼消瘤方中的5个皂苷类成分进行分析,能有效地消...     

高效液相色谱二极管阵列检测法同时测定丹参滴注液中四种水溶性成分的含量

建立了高效液相色谱二极管阵列检测(HPLC-DAD)法同时测定丹参滴注液中丹参素、原儿茶醛、迷迭香酸和丹酚酸B四种水溶性成分的含量。采用DiamonsilTMC18色谱柱(250×4.6 mm,5μm),以甲醇和5%冰乙酸为流动相进行梯度洗脱,流速为1.0mL/min,柱温30℃,检测波长为286 nm。在此色谱条件下四种水溶性成分可完全分离。丹参素、原儿茶醛、迷迭香酸和丹酚酸B的线性范围分别为0.2192~1.934μg(r=0.9999),0.03508~0.2456μg(r=1.0000),0.2592~1.814μg(r=1.0000),0.3864~2.705μg(r=0.9999)。平均回收率丹参素为102.6%,相对标准偏差(RSD)为0.55%;原儿茶醛为103.5%,RSD为0.42%;迷迭香酸为99.8%,RSD为0.68%;丹酚酸B为102.8%,RSD为0.49%。该方法简单、快速,四组分分离良好,可用于丹参滴注液的质量控制。     

分散固相萃取-高效液相色谱-串联质谱法测定蜂蜜中生物碱

建立了分散固相萃取-高效液相色谱-串联质谱法(QuEChERS-HPLC-MS/MS)同时测定蜂蜜中吡咯里西啶生物碱(倒千里光、千里光菲林、千里光宁、克氏千里光宁)和异喹啉类生物碱(小檗碱、荷叶碱)的方法。蜂蜜样品经乙腈提取,乙二胺-N-丙基硅烷(PSA)吸附剂净化,HPLC-MS/MS测定。采用Agilent Poroshell 120SB-C18色谱柱(100 mm×2.1 mm,2.7μm)分离。以0.1%甲酸溶液和乙腈为流动相进行梯度洗脱,电喷雾正离子(ESI+)模式电离,多反应监测模式(MRM)下进行测定,外标法定量。结果表明,在0.1~100μg/L范围内,6种生物碱的相关系数均大于0.99;在1~100μg/kg的添加水平下,所有生物碱回收率均在70%~110%之间;6种生物碱日内精密度小于15%,日间精密度小于20%;方法检出限和定量限分别为0.3和1.0μg/kg。本方法可用于蜂蜜中吡咯里西啶生物碱和异喹啉类生物碱的同时定性和定量分析。     

超高效液相色谱-串联质谱法快速分析烟叶中的8种生物碱

采用超高效液相色谱-串联质谱(UPLC-MS-MS)建立了快速分析烟叶中8种生物碱的分析方法。50 mg烟叶粉末样品经2 mL 6%氨水浸润后，以10 mL二氯甲烷超声提取20 min,有机相用N-丙基-乙二胺(PSA)净化后氮吹近干，再以乙腈超声复溶后用UPLC-MS-MS分析。烟叶中8种生物碱(烟碱、新烟碱、新烟草碱、降烟碱、二烯烟碱、2,3′-联吡啶、可替宁、麦斯明)的平均回收率在86.5%～102%之间，相对标准偏差(n=6)为2.1%～5.4%;方法对烟碱的检出限为0.45 mg/g,定量限为1.5 mg/g;对其余7种微量生物碱的检出限在0.15～0.6μg/g之间，定量限在0.5～2μg/g之间。本方法适用于烟叶中8种生物碱含量的快速测定。     

固相萃取-超高效液相色谱-电喷雾串联质谱法测定调味品中的罗丹明B

利用超高效液相色谱-电喷雾串联质谱(UPLC-MS/MS)方法测定了调味品中罗丹明B。样品经乙腈-乙酸水溶液提取后,经固相萃取(SPE)柱净化,采用BEH C18柱分离,以乙腈和0.2%的甲酸水溶液为流动相进行梯度洗脱,采用正离子、多反应监测(MRM)模式进行定性定量测定。罗丹明B在0.5～500μg/L质量浓度范围内线性关系良好,相关系数r为0.999,检出限、定量限分别为0.03,0.10μg/kg;平均回收率为86.6%～95.7%,标准偏差小于10%。方法适用于调味品中罗丹明B的测定。     

高效液相色谱法测定桂利嗪原料中4种有关物质

建立高效液相色谱法测定桂利嗪原料中4种有关物质的方法。采用Thermo Hypersil C18(100 mm×4.0mm,3μm)色谱柱,以10 g/L乙酸铵溶液-0.1%冰乙酸乙腈溶液为流动相进行梯度洗脱,流量为1.5 mL/min,检测波长为230 nm,柱温为30℃,进样体积为10μL。桂利嗪的质量浓度线性范围为1.25～125μg/mL,相关系数为0.999 9,4种杂质的质量浓度线性范围为1.25～125μg/mL,相关系数为0.999 7～0.999 9。桂利嗪检出限为0.2μg/mL,杂质A检出限为0.1μg/mL,杂质B、杂质C、杂质D检出限均为0.25μg/mL。杂质A、杂质B、杂质C、杂质D测定结果的相对标准偏差分别为3.4%、2.4%、2.8%、1.8%,平均加标回收率分别为103.4%、100.4%、101.1%、101.3%。该方法专属性强,重复性好,可有效控制桂利嗪原料的质量,保证已知杂质的有效检出。     

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%.     

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.     

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.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

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.     

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.