流动注射化学发光法测定大豆异黄酮

基于在NaOH碱性介质中,K3Fe(CN)6可以直接氧化大豆异黄酮产生强的化学发光这一现象,并结合流动注射分析技术,提出了直接化学发光测定大豆异黄酮含量的新方法。当K3Fe(CN)6浓度为5.0×10-4mol/L,NaOH浓度为0.5 mol/L,主副蠕动泵转数分别为45 r/m in和35 r/m in时,体系具有最强的化学发光。该方法测定大豆异黄酮的线性范围为1.0×10-3~0.5 g/L;其回归方程为A(峰面积)=193305C(mg/L) 229.97,r=0.9962;检出限为4.6×10-4g/L。对5.0×10-3g/L大豆异黄酮溶液连续测定,每次得3个峰值,重复7次,相对标准偏差为2.46%。本方法已用于大豆中异黄酮含量的测定。     

高效液相色谱法检测保健食品中大豆异黄酮含量

建立了保健食品中大豆异黄酮的高效液相色谱检测方法 ,通过正交试验法得出保健食品中大豆异黄酮的最佳水解条件为 :盐酸浓度2.0mol/L,酸体积40mL ,水解温度80℃ ,水解时间3h;采用HypersilODS2C18 色谱柱 (250mm×4.6mmID ,5μm) ,流动相为甲醇 -水(体积比47∶53) ,流速1.0mL/min ,检测波长260nm ,柱温40℃ ,线性范围在0.5～96mg/L ,相关系数r为0.999 ,相对标准偏差 (RSD)2.09% ,回收率在98.5 %～100.5 %。     

人尿中异黄酮的高效液相色谱分析

建立了测定人尿中异黄酮组分(大豆苷原、黄豆黄素、雌马酚、染料木黄酮)含量的反相高效液相色谱法。在尿样中加入黄酮作为内标,异黄酮经酶解后在pH=7.0中性条件下用乙酸乙酯(1∶1)提取,然后用0.02%TFA-M eOH-ACN三元梯度洗脱的方法分离异黄酮。在该条件下,大豆苷原、黄豆黄素、雌马酚、染料木黄酮的检出限分别为12.9 nmol/L、13.9 nmol/L、71.6 nmol/L和11.8 nmol/L;回收率均在89%以上。本方法具有测试步骤简单、准确度高、重现性好等优点,适合大批量样品测定。     

高效液相色谱法同时测定黄芪中的五种异黄酮类成分

对蒙古黄芪中5种异黄酮类成分的含量进行了反相高效液相色谱法测定。色谱柱为Diamonsil C18柱,流动相为乙腈-水系统,梯度洗脱,检测波长230 nm,柱温35 ℃。毛蕊异黄酮-7-O-β-D-葡萄糖苷在20.12～201.2 mg/L、芒丙花素-7-O-β-D-葡萄糖苷在4.62～46.2 mg/L、9,10-二甲氧基紫檀烷-3-O-β-D-葡萄糖苷在4.86～48.6 mg/L、毛蕊异黄酮在9.24～92.4 mg/L、芒丙花素在6.92～69.2 mg/L时峰面积与浓度呈良好的线性关系,相关系数分别为0.9992,0.9997,0.9997,0.9995和0.9995。5种成分的加样回收率均高于94%,相对标准偏差（RSD）小于3.2%(n=9)。该法简便快速,重复性良好,结果准确可靠,可用于黄芪药材中5种主要异黄酮类成分的含量测定。     

高效液相色谱法测定保健食品中的大豆异黄酮

建立了一种测定保健食品中大豆异黄酮的高效液相色谱分析方法,该方法可以使常见的大豆异黄酮6种主要成分大豆甙、黄豆甙、染料木甙、大豆甙元、黄豆黄素、染料木素得以分离和检测。采用乙腈-磷酸水溶液(pH2.8)作流动相,梯度洗脱,Venusil MP-C18色谱柱(150 mm×4.6 mmi.d.,5μm),流速为1.0 mL/min,紫外检测器,检测波长254 nm。结果表明各组分线性关系良好,相关系数R2为0.9991~0.9998,加标回收率在87%~106.9%,相对标准偏差均小于2%。检出限0.25~0.48μg/mL,该方法可同时测定大豆异黄酮的6种成分。     

反相高效液相色谱法制备纯化大豆异黄酮糖苷

利用制备高效液相色谱法从大豆总异黄酮提取物中制备出了3种大豆异黄酮糖苷。在Nova-Pak HR C18色谱柱(100 mm×25 mm i.d.,6 μm)上,以甲醇-体积分数为0.1%的乙酸水溶液(体积比为23∶77)为流动相,流速为20 mL/min,采用 等度洗脱方式,制备了3种大豆异黄酮糖苷,经质谱分析,确认它们分别为大豆苷、黄豆苷和染料木苷。高效液相色谱分析 表明,所制备的3种化合物的纯度均达到了99%以上。     

高效液相色谱法测定保健食品中大豆异黄酮含量

建立了高效液相色谱法(HPLC)测定保健食品中大豆异黄酮含量的方法,运用二极管阵列检测器(PDA)建立了4种大豆异黄酮D、G、De、Ge的光谱库,测定了D、G、Ge与De响应值之比.采用PDA检测,C18反相柱,以甲醇∶水∶醋酸(HAC)=55∶45∶1(V/V/V)为流动相测定了同一批保健食品美龄营养片中4种大豆异黄酮D、G、De、Ge的含量分别为2.24%、10.82%0、.085%、0.027%,变异系数小于5%,回收率为92.51%～99.30%.该方法快速,精密度及准确度在允许范围内,可作为保健食品中D,G,De,Ge的同时测定方法.     

HPLC法测定豆制品中游离异黄酮的含量

利用高效液相色谱法（HPLC）对豆制品中的大豆黄素和染料木素的含量进行测定，从而研究豆制品加工中的游离大豆异黄酮分布情况。     

加压毛细管电色谱测定葛根中三种异黄酮类化合物

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。     

电合成2,2-二羟甲基丙酸

制备Ti/SnO2+Sb2O4/PbO2电极,电极的组分及其价态由XRD和XPS表征;该电极可将2,2-二羟甲基丙醛直接电合成2,2-二羟甲基丙酸.应用高效液相色谱分析原料和产物,电化学方法研究电合成影响因素,包括:2,2-二羟甲基丙醛浓度、溶液pH值、反应温度和氧化电位等.在优化条件下(pH=1,C醛=0.10 mol.L-1,t=15℃,E=1.8 V)电合成2,2-二羟甲基丙酸的转化率为58%,选择性36%,电流效率28%.本法为该产物的合成提供了一种新的途径.     

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.