制备型高效液相色谱法分离纯化川西獐牙菜提取物中的龙胆苦苷

龙胆苦苷(GPS)是龙胆类药材及其相关制品质量控制的指标成分。本研究利用制备型高效液相色谱从川西獐牙菜提取物中分离纯化龙胆苦苷对照品。对制备色谱的流动相组成、流速、进样量和检测波长等制备参数进行了优化。采用的色谱柱为C18柱(200 mm×50 mm, 5 μm),流动相为甲醇和0.1%乙酸水溶液(体积比为30:70),流速为75 mL/min,检测波长为254 nm,进样体积为500 μL。在30 min的运行时间内,龙胆苦苷与其他干扰成分得到了很好的分离,产品纯度达到了99%以上。此方法具有快速高效、产品纯度高的特点,可用于制备龙胆苦苷对照品和对龙胆苦苷制品的质量控制。     

青藏高原龙胆属中10种野生药材的4种主要活性成分的测定分析

建立反相高效液相色谱法同时测定青藏高原龙胆属中10种常用野生药材的獐牙菜苦苷、龙胆苦苷、獐芽菜苷、异荭草苷的含量.方法:采用反相高效液相色谱法.乙腈-水(0.1%的H3PO4)为流动相,梯度洗脱,洗脱条件为0.01 min→20.00 min→20.01 min→40.00 min→40.01 min→50.00 min,乙腈:12%→12%→15%→33%→100%→100%,体积流量1.0 mL/min,检测波长为240 nm,柱温25 ℃.4种成分均达到基线分离,线性良好.     

女贞子中红景天苷的HPLC制备分离

研究了制备型高效液相色谱分离纯化女贞子中红景天苷的方法。制备色谱的参数为:色谱柱为C18柱(50 mm×200 mm,5μm),流动相为甲醇-水(体积比为7.5∶92.5),流速100 mL·min-1,二级管阵列检测器在278 nm检测,进样体积为2.2 mL。在18 min的运行时间内,红景天苷与干扰成分得到很好的分离,经HPLC检测纯度均达到98%以上。此方法具有快速高效、分离组分纯度高的特点,可用于制备红景天苷。     

高速逆流色谱法从秦艽地上部分制备分离龙胆苦苷

采用高速逆流色谱法分离纯化秦艽地上部分中的龙胆苦苷。溶剂系统为V(氯仿)∶V(甲醇)∶V(水)=4∶4∶2,上相为固定相,下相为流动相,转速为800r/min,流速为2mL/min。所得产物经LC-MS分析为龙胆苦苷,纯度经高效液相色谱分析为94.0%(峰面积归一化法)。在保证分离效果的前提下,增大进样量,摸索制备分离龙胆苦苷的高速逆流色谱条件,为用高速逆流色谱法大量制备龙胆苦苷提供了一个可行方法。     

藏药麻花艽中四种苦苷类化学成分的HPLC测定

建立了藏药麻花艽中龙胆苦苷(gentiopicroside)、落干酸(loganic acid)、獐牙菜苦苷(swertiamarin)和獐牙菜苷(sweroside)4种苦苷类成分的HPLC分析方法。色谱柱为Eclipse XDB-C8(4.6 mm i.d.×150 mm,5μm),流动相为体积分数5%乙腈 10 mmoL甲酸~95%乙腈水溶液,检测波长为240 nm。结果表明,该方法具有良好的线性关系和回收率,为麻花艽中苦苷类成分的进一步开发利用提供了科学依据。     

HPLC测定云雾龙胆花中獐牙菜苷和异荭草苷的含量

建立云雾龙胆花中獐牙菜苷和异荭草苷含量测定的HPLC方法。采用微波辅助动态回流法进行提取,色谱条件:Fusion-RP 80 A C18柱(150×4.6 mm,5μm);流动相:甲醇-0.2%磷酸溶液梯度洗脱(0~20 min∶18∶82~30∶70;20~30min∶30∶70~40∶60;30~35min∶40∶60~50∶50);流速:1 mL/min;柱温:30℃;检测波长254 nm。云雾龙胆花中獐牙菜苷和异荭草苷的色谱峰与共存组分完全达到基线分离,线性范围分别为0.25~1.25μg(r=0.9998),0.432~2.160μg(r=0.9999),平均加样回收率分别为97.7%(RSD=0.84%),99.2%(RSD=0.76%)。     

高效液相色谱法同时测定葛枳胶囊中5种有效成分的含量

提出了高效液相色谱法同时测定葛枳胶囊中5种有效成分(葛根素、大豆苷、甘草苷、大豆苷元和甘草酸)的含量。样品经甲醇-水(50+50)溶液超声提取30min,采用Diamonsil C18色谱柱(200mm×4.6mm,5μm)为分离柱,以不同体积比混合的乙腈和磷酸(0.1+99.9)混合液为流动相进行梯度洗脱,甘草苷的检测波长为276nm,其余4种成分均为250nm。5种有效成分分别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0.050～0.338mg·L-1之间。方法的回收率在97.1%～104%之间,测定值的相对标准偏差(n=6)在1.0%～2.7%之间。     

藏药达乌里秦艽中环烯醚萜苷的HPLC测定

采用HPLc法同时测定了藏药达乌里秦艽中龙胆苦苷(gentiopicroside)、獐牙菜苦苷(swertiamarin)、獐牙菜苷(sweroside)和落干酸(loganic acid)4种主要环烯醚萜苷类成分,利用在线质谱(MS)进行了定性分析,并与同属藏药麻花艽进行了比较.色谱柱为Eclipse XDB-C8(4.6 mm×150 mm i.d.,5 μm),流动相A:体积分数5%乙腈(含10 mmol甲酸)水溶液,流动相B:体积分数95%乙腈水溶液,以流动相A在0～15 min内由100%线性减至90%,15～20 min内保持90%不变线性梯度洗脱.流速1.0 mL/min,检测波长240 nm,柱温30℃.结果表明,4种成分均达到了基线分离,具有较好的线性关系和回收率.本法可作为达乌里秦艽药材有效成分的测定方法,为其有效成分的进一步开发利用提供依据.     

高效液相色谱法同时测定舒胆片中栀子苷、虎杖苷、柚皮苷和新橙皮苷

建立同时测定舒胆片中栀子苷、虎杖苷、柚皮苷和新橙皮苷含量的高效液相色谱法.选择Kromasil 100–5–C18柱(4.6 mm×250 mm,5μm)为分离柱,以乙腈–水为流动相,梯度洗脱,流量为1.0 mL/min,柱温为30℃,检测波长:0～13 min时为238 nm,13～17 min时为306 nm,17...     

高效液相色谱法分析谷氨酸棒杆菌细胞内尿苷二磷酸葡萄糖和尿苷二磷酸半乳糖

建立了利用高效液相色谱分离分析谷氨酸棒杆菌细胞内尿苷二磷酸(UDP)葡萄糖与UDP半乳糖的新方法,考察了不同色谱柱、不同分离模式及不同流动相组成对UDP葡萄糖和UDP半乳糖的保留特性及分离度的影响。结果表明,在Zorbax NH2柱(250 mm×4.6 mm i.d.,5 μm)上以0.125 mol/L KH2PO4缓冲液(pH 3.6)-乙腈(体积比为40∶60)溶液为流动相,可使谷氨酸棒杆菌细胞内的两种中间代谢产物UDP葡萄糖与UDP半乳糖在22 min内达到基线分离。该方法对UDP葡萄糖和UDP     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

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.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

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.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

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%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

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.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

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.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

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.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.