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为检测杜仲中维生素K1含量,采用了特异性强、分离效果好的高效液相色谱(HPLC)法,将样品经丙酮、石油醚提取,用失活磷酸盐处理过的氧化铝进行柱色谱净化处理,用极性不同的洗脱液将维生素K1从样品中分离出来,收集V(石油醚) V(乙醚)=97 3洗脱组分,浓缩定容,用C18色谱柱对维生素K1进行定性定量分析,流动相为V(甲醇) V(正己烷)=75 25,紫外检测波长为248 nm。结果表明,在流量为1.5 mL/min的条件下,维生素K1的保留时间为(2.18±0.1)min,r为0.999 3,回收率87.67%~95.12%,杜仲中的维生素K1含量为12.404 3μg/g。 相似文献
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HPLC法测定浓缩当归丸中阿魏酸的含量 总被引:6,自引:0,他引:6
建立了浓缩当归丸中阿魏酸的HPLC测定方法.采用C18色谱柱(TSK-GEL,4.6×150 mm,5μm),以甲醇-水-磷酸(30∶70∶0.3,V/V/V)为流动相,流速1.0 mL/min,检测波长320 nm.结果阿魏酸在0.006~0.15μg范围内线性关系良好,r为0.9999,平均加样回收率为96.91%.本方法可用于浓缩当归丸中阿魏酸的含量监控. 相似文献
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凝胶净化-高效液相色谱法检测对位红在辣椒酱和辣酱油中的残留量 总被引:7,自引:0,他引:7
运用高效液相色谱(HPLC)法分析并采用凝胶净化系统(GPC)预处理,建立了测定辣椒酱、辣酱油等复杂样品中对位红残留量的检测方法。辣椒酱、辣酱油样品用乙腈提取,经过净化、浓缩,用乙腈定容进行检测。色谱柱为资生堂MG-ⅡC18柱,直接采用等度洗脱,流动相为乙腈-水;采用可变波长检测器(VWD),检测波长为485 nm。对位红标准溶液在0.02~1.0 mg/L浓度范围内,药物峰面积与浓度呈良好的线性关系,其相关系数的平方(R2)为0.9978。辣椒酱、辣酱油样品中添加药物回收率分别为:71.0%±2.5%~90.4%±4.0%和72.1%±3.1%~91.8%±2.0%;对位红在复杂样品中的残留量检测的定量限为0.05μg/g。 相似文献
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本文提出了一种采用高效液相色谱/荧光检测法(HPLC/FLD)测定麦类样品中赭曲霉毒素A的方法.样品经V(乙腈):V(水)=84:16提取,多功能柱净化,C18色谱柱(4.6×250 mm,5μm)分离,V(水):V(乙腈):V(乙酸)=102:96:2作流动相,流速1.0 mL/min.结果表明,标准工作液在浓度1.0~50.0μg/L范围内,峰面积与浓度成良好的线性关系,线性相关系数>0.9999,样品在3.0,10.0,50.0 ng/g添加水平的回收率为60%~85%,相对标准偏差为7.9%~8.8%(n=8),方法检出限为3.0 ng/g(S/N>10).本法快速、准确、操作简单,可满足大批麦类样品的检测需要. 相似文献
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建立了8-硝基-1,3,6-萘三磺酸(硝基T酸)加氢还原的中间产物的HPLC/MS的分析方法。液相色谱条件如下:Hypersil ODS2色谱柱(5μm,4.6 mm×250 mm),流动相为V(甲醇)∶V(水)∶V(乙酸)∶V(三乙胺)=7∶92.1∶0.6∶0.3,流速0.5 mL/min,检测波长234 nm。采用面积归一化法对样品进行定量分析,采用液质联用鉴定硝基T酸加氢还原的中间产物。该方法可用于监测硝基T酸加氢还原的生产过程,并为其它磺酸类化合物的定量和定性分析提供借鉴。 相似文献
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高效液相色谱柱后衍生测定鸡组织中甲基盐霉素残留量 总被引:2,自引:0,他引:2
建立了鸡组织中甲基盐霉素的高效液相色谱柱后衍生化分析方法.样品经异辛烷提取,离心后上层有机相过硅胶固相萃取小柱,洗脱液浓缩后用V(甲醇)∶ V(水)=90∶ 10混合液溶解.采用Inertsil ODS-3 C18柱,以V(甲醇): V(乙酸)∶ V(水)=94∶ 3∶ 3为流动相,香草醛为衍生剂进行高效液相色谱柱后衍生分析,520 nm检测,外标法定量.方法检出限为6 μg/kg; 定量限为20 μg/kg; 添加浓度在20~1800 μg/kg范围内,平均添加回收率为76.4%~93.1%; 批内相对标准偏差(RSD)在2.6%~8.9%之间; 批间相对标准偏差(RSD)在4.7%~9.7%之间.样品浓度在0.07~10.0 mg/L范围内与峰面积呈良好的线性关系,r>0.9993. 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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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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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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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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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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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