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建立一测多评高效液相色谱法同时测定五味子中五味子醇甲、五味子甲素、五味子乙素含量的方法,并验证该法的可行性和准确度。通过Plackett-Burman设计考察流动相中甲醇比例、流动相流量、柱温、进样体积对五味子醇甲色谱峰分离度的影响,确定流动相中甲醇比例、柱温为关键分析参数(P<0.05)。通过中心组合设计优化关键分析参数,建立色谱分析条件:以甲醇-水(体积比为70∶30)溶液作为流动相进行洗脱,流量为1.0 mL/min,柱温为35℃,检测波长为254 nm,进样体积为10μL。以五味子醇甲为内参物,分别建立五味子甲素、五味子乙素与五味子醇甲的相对校正因子,计算各成分含量,实现一测多评。采用外标法测定五味子甲素、五味子乙素含量,比较外标法的实测值与一测多评法预测值之间的差异,以验证一测多评法的准确度及可行性。五味子中五味子醇甲与五味子甲素、五味子乙素的相对校正因子分别为1.039、1.246。五味子醇甲、五味子甲素、五味子乙素色谱峰面积与质量浓度在5~500μg/mL范围内呈良好的线性关系,相关系数均大于0.999。样品加标回收率分别为100.1%、100.6%、100.3%,... 相似文献
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应用高效液相色谱法测定北五味子中五味子醇甲、五味子酯甲、五味子甲素、五味子乙素和五味子丙素等5种木脂素的含量。北五味子样品(1.000g)在70℃温度下用甲醇(20mL)微波辅助提取5min。分取部分提取液,以Hypersil ODS C18色谱柱为固定相,用乙腈和水以不同比例混合的溶液为流动相进行梯度洗脱,在检测波长225nm处进行测定。5种木脂素在一定的质量浓度范围内与其峰面积呈线性关系,方法的检出限(3S/N)在0.029 2~0.050 7mg·L-1之间。以样品为基体,在3个浓度水平加入混合标准溶液进行回收试验,测得回收率在95.3%~101%之间,测定值的相对标准偏差(n=6)在1.1%~2.4%之间。 相似文献
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王哲申书昌辛杨 《理化检验(化学分册)》2018,(8):896-900
采用超高效液相色谱-质谱法测定醋五味子中五味子酯甲、五味子酚、五味子甲素、五味子乙素、五味子丙素、五味子醇甲和五味子醇乙等7种木脂素的含量。醋五味子样品0.200 0g用甲醇10mL超声提取30min。以ACQUITY UPLC BEH C_(18)色谱柱为分离柱,以不同体积比的乙腈和0.1%(体积分数)甲酸溶液的混合液为流动相进行梯度洗脱,质谱分析中采用电喷雾正离子源和选择离子监测模式。7种木脂素的质量浓度在一定范围内与其对应的峰面积呈线性关系,方法的检出限(3S/N)为0.001~0.050mg·L^(-1)。对6.0mg·L^(-1)的7种木脂素混合标准溶液连续测定6次,测定值的相对标准偏差为1.2%~3.5%。方法用于醋五味子样品的分析,加标回收率为85.4%~99.3%。 相似文献
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采用超高效液相色谱-质谱法测定醋五味子中五味子酯甲、五味子酚、五味子甲素、五味子乙素、五味子丙素、五味子醇甲和五味子醇乙等7种木脂素的含量。醋五味子样品0.200 0g用甲醇10mL超声提取30min。以ACQUITY UPLC BEH C_(18)色谱柱为分离柱,以不同体积比的乙腈和0.1%(体积分数)甲酸溶液的混合液为流动相进行梯度洗脱,质谱分析中采用电喷雾正离子源和选择离子监测模式。7种木脂素的质量浓度在一定范围内与其对应的峰面积呈线性关系,方法的检出限(3S/N)为0.001~0.050mg·L~(-1)。对6.0mg·L~(-1)的7种木脂素混合标准溶液连续测定6次,测定值的相对标准偏差为1.2%~3.5%。方法用于醋五味子样品的分析,加标回收率为85.4%~99.3%。 相似文献
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建立了舒肝益脾颗粒一测多评(QAMS)的高效液相色谱(HPLC)测定方法,并验证该方法在质量控制中的适用性与准确性。该方法能较好地分离舒肝益脾颗粒中3种主要成分(五味子醇甲、五味子甲素、五味子乙素),并以五味子醇甲为内参物,建立五味子甲素、五味子乙素与其之间的相对校正因子(fs/k),用fs/k计算各代表性成分含量,实现一测多评。在各自线性范围内,采用多点校正法得到五味子醇甲与甲素、五味子乙素之间的fs/k分别为0.94、0.95,且在不同品牌色谱仪、色谱柱下有较好的重复性。同时将一测多评的计算值(多点校正法与斜率校正法)与外标法实测值进行比较,两者结果无差异。一测多评法可同时对舒肝益脾颗粒中上述3种成分进行含量测定,方法简便、准确、可靠,可有效控制舒肝益脾颗粒的质量。 相似文献
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本文以四(4-三甲铵苯基)卟啉作显色剂,在阳离子表面活性剂CPB存在下的pH9.8缓冲溶液中,利用三阶导数分光光度法,对钴、镉、铅的同时测定进行了详细研究。本方法测定灵敏度较高,对合成样品进行测定,结果令人满意。 相似文献
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An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions. 相似文献
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An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction. 相似文献
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The Diels-Alder reactivity of 1,2-heteroborines (H4C4B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed. 相似文献
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Xi-Liu YunWen-Ying Bi Jian-Hui HuangYu Liu Daisy Zhang-NegrerieYun-Fei Du Kang Zhao 《Tetrahedron letters》2012,53(38):5076-5080
A variety of N-aryl and N-alkyl carbazolones were conveniently achieved in good to high yields via Pd2(dba)3-mediated intramolecular coupling of N-substituted α-iodo enaminones under microwave irradiation. The Pd(0)-catalyzed cyclization was found to proceed favorably with the more electron-deficient phenyl ring during the reactions involving unsymmetrical N,N-diaryl α-iodo enaminones. This unique property enables the construction of carbazolone skeleton containing nitro substituted benzenoid ring. 相似文献
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Both substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles have been synthesized by the 3+2 intramolecular dipolar cycloaddition of nitrilimines to alkynes. This cyclization has been extended to more versatile 3-bromo derivatives by the use of alkynylbromides as dipolarophiles. 相似文献
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An efficient and benign method for the preparation of aminomethyl-substituted fullerenes has been developed. The process, involving catalyst free, visible-light irradiation of 10% EtOH-toluene solutions containing fullerene C60 and N-trimethylsilylmethyl-substituted amines by using a 20 W compact fluorescent lamp, leads to formation of aminomethyl-substituted fullerene adducts in a highly efficient manner. The photoaddition reaction takes place via a pathway initiated by visible light absorption by C60, followed by SET from the amine to the triplet excited state of C60. Ethanol-promoted desilylation of the resulting a minimum radical then generates the corresponding α-amino radical which couples with the C60 radical anion to form the anion precursor of the fullerene adducts. The new approach using visible-light takes place under mild conditions and it does not require the use of photocatalysts. Thus, the method developed in this effort could broadens the range of functionalized fullerene derivatives that can be readily prepared. 相似文献
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Viktor A. Dmitriev Mariia M. Efremova Alexander S. Novikov Vladimir V. Zarubaev Alexander V. Slita Anastasia V. Galochkina Galina L. Starova Andrey V. Ivanov Alexander P. Molchanov 《Tetrahedron letters》2018,59(24):2327-2331
The reactions of various nitrones with indolyl- and pyrrolylacrylates proceeds regioselectively with high diastereoselectivity in the case of aldonitrones, and represents an effective method for obtaining new indolyl- and pyrrolyl-substituted isoxazolidine carboxylates stabilized by weak (CH?O) and moderate (NH?N) strength intramolecular hydrogen bonding. The resulting cycloadducts exhibit promising in vitro anti-influenza activities. 相似文献
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A transition metal-free method for the direct amination of benzoxazoles using formamides as nitrogen sources is reported, which was mediated by an inexpensive and environmentally friendly tetrabutylammonium iodide/tert-butyl hydroperoxide system and gave the 2-aminobenzoxazole derivatives with moderate to good yields. 相似文献
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Multifunctionalized 1,2,3,4-tetrahydropyridines are concisely synthesized in good yields via l-proline-catalyzed or l-proline/FeCl3-cocatalyzed one-pot multicomponent reactions (MCRs). The MCRs involve a domino hydroamination/prins reaction/Mannich-type reaction/intramolecular dehydration-cyclization process. The molecular structure of 5baa, one of multifunctionalized 1,2,3,4-tetrahydropyridines, was confirmed by single-crystal X-ray diffraction. 相似文献
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Yin Shuhui Liu Hongping Zhang Jianyang Jiang Bo Wang Li Sha Guohe Lou Nanquan 《化学物理学报(中文版)》2003,16(1):3-8
The multi-photon dissociative photoionization dynamics of CF3I has been studied with femtosecond two-color pump-probe time of flight mass spectra at a pump pulse of 265 nm and a probe pulse of 398 nm. The life constants of CF3I+ and its fragment ions CF3+ and I+ are obtained as (96±7), (198±130) and (167±6)fs, respectively. The multi-photon dynamics leading to these ions differ. CF3I+ corresponds to a (1+2′) transition with one-photon pump excitation to the A band of CF3I. CF3+ are mainly formed by a tow-photon probe excitation to the CF3+ with subsequent dissociation of parent ions. I+ are produced in (2+2′) combined with (1+1′+2′) process. The results provide information on the multi-photon pathways involved. 相似文献