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提出了高效液相色谱-串联质谱法测定葛根中葛根素和大豆苷元的含量。样品经乙醇提取,所得提取液用乙醇定容至100mL后经Waters Xterra MS C18色谱柱(150mm×3.9mm,5μm)分离,用乙腈与50mmol.L-1甲酸溶液(40+60)的混合液洗脱,采用电喷雾正离子电离多反应监测模式。葛根素和大豆苷元的质量浓度分别在0.050~0.50mg.L-1和5.0~50mg.L-1之间与峰面积呈线性关系,检出限(3S/N)均为5μg.L-1。在0.1,1.0,10.0mg.L-1 3个浓度水平进行加标回收试验,葛根素和大豆苷元的回收率分别为96.6%和97.4%。 相似文献
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应用高效液相色谱-二极管阵列联用仪(HPLC-DAD)结合基于交替三线性分解(ATLD)算法的二阶校正方法快速测定了中药葛根样中主要活性成分葛根素、大豆苷和大豆苷元的含量,实现了同时定量分析.色谱条件:甲醇-水(体积比为53∶47),检测波长范围为190~380nm,柱温为30℃,流速为1.0mL/min,进样量为20.0μL.预测的实际样中三种目标分析组分葛根素、大豆苷、大豆苷元的含量分别为(0.465±0.023),(0.553±0.015)和(0.098±0.005)mg/g,它们的加标回收率分别为(101.1±3.2)%,(100.4±6.4)%和(100.1±4.9)%. 相似文献
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《分析试验室》2021,40(9):1010-1014
建立了加压毛细管电色谱(pCEC)检测葛根中异黄酮类化合物葛根素、大豆苷、大豆苷元的方法。采用C18毛细管色谱柱,以NaH2PO4缓冲盐水溶液和甲醇为流动相,优化流动相比例、流动相流速、NaH2PO4缓冲盐水溶液浓度和pH、分离电压等色谱条件。结果表明,在流动相为17.5 mmol/L NaH2PO4缓冲盐水溶液(pH 4.0):甲醇=55:45(V/V),分离电压3 kV,流动相流速80μL/min,检测波长250 nm的条件下,葛根素、大豆苷、大豆苷元质量浓度在200~1000μg/mL范围内线性关系良好,相关系数在0.9960~0.9982之间,平均回收率在98.6%~100.9%之间,RSD为3.1%~3.5%之间。该方法已用于葛根中异黄酮类物质的分离检测。 相似文献
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建立了11种心血管保健功效成分(天麻素、吡啶甲酸铬、腺苷、大豆苷元、大豆苷、染料木苷、染料木素、红景天苷、葛根素、芦丁、淫羊藿苷)的反相高效液相色谱同时检测法,采用C18柱,在25℃,1 mL/min流速下,以甲醇-KH2PO4二元流动相梯度洗脱,二极管阵列检测器检测。在单因素实验基础上,采用响应曲面法对提取工艺进行了进一步优化。方法在25 min内实现基线分离,线性相关系数r≥0.9985,检出限范围为0.008~0.20μg/mL,日内精密度≤1.5%,日间精密度≤5.0%,回收率在85.0%~98.2%之间。 相似文献
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建立反相高效液相色谱法测定苁蓉酒中松果菊苷含量。固定相为C18,流动相为甲醇-0.1%甲酸水溶液(体积比为33:67),流速1.0mL/min,柱温为30℃,检测波长为330nm。松果菊苷的浓度x(mg/mL)与其峰高y呈良好的线性关系,线性方程为Y=2.5955x,相关系数为0.9999。样品的加标回收率为88.1%~107.5%,测定结果相对标准偏差为0.41%(n=5)。 相似文献
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高效液相色谱/质谱分析抱茎獐牙菜提取物中的苷性成分 总被引:4,自引:0,他引:4
采用高效液相色谱/质谱法(HPLC/MS)分析抱茎獐牙菜提取物中5种苷性成分。在C18柱上,以甲醇(A:含20%水)和水(B:含10%甲醇)为流动相,流速1mL/min,线性梯度洗脱B从100%到0%,35min,液相色谱-质谱质联用(LC/MS),大气压化学电离源(APCI),对其中5种苷性成分进行定性鉴定。经HPLC/APCIMS分析确证,抱茎獐牙菜提取物中含有獐牙菜苦苷(swertiamarin)、龙胆苦苷(gentiopicroside)、獐牙菜苷(sweroside)、异红草苷(isoorientin)和獐牙菜山酮苷(swertianolin)。采用外标法定量,回收率分别为98.3%、106.7%、92.3%、88.2%和107.3%,该方法简便、快速、准确。 相似文献
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大豆中6种磺酰脲类除草剂残留量的高效液相色谱-质谱法测定 总被引:4,自引:2,他引:4
建立了LC—MS选择离子监测(SIM)同时检测大豆中6种磺酰脲类除草剂残留量的方法。样品经乙腈提取,正己烷液-液分配,Florisil柱净化,然后采用HPIE—ESI( )-MS测定。6种磺酰脲类除草剂在25~1000μg/L范围内线性良好,相关系数为0.9996~0.99977在0.02~1.0mg/kg范围内,平均加标回收率在72%~99%之间,相对标准偏差为0.9%~7.7%。方法的检出限低于10μg/kg。 相似文献
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Uroš Grošelj Mojca Žorž Amalija Golobič Branko Stanovnik Jurij Svete 《Tetrahedron》2013,69(52):11092-11108
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives. 相似文献
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The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion. 相似文献
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N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%). 相似文献
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Shashikant U. Dighe Surya K. Samanta Shivalinga Kolle Sanjay Batra 《Tetrahedron》2017,73(17):2455-2467
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones. 相似文献
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In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates. 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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Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described. 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