四羧基镍酞菁共振散射法测定蛋白质

建立了一种测定蛋白质的新方法．在pH3．6的Britton-Robinson（B-R）缓冲溶液中,蛋白质与四羧基镍酞菁NiPc（COOH）4发生相互作用,使体系在λ=388nm处的共振散射（RLS）增强,并且增强的散射强度（IRLS）与蛋白质的含量成比例,据此利用四羧基镍酞菁NiPc（COOH）4为光谱探针共振散射法测定人血清中的总蛋白质,同时优化了体系光散射检测的实验参数．在最佳的实验条件下,对牛血清白蛋白（BSA）、人血清白蛋白（HSA）、人血清总蛋白（TP）的线性范围分别为0．00～1．20mg／L、0．00～1．00mg／L、0．00～1．00mg／L,相应检测限分别为5．97×10^-4mg／L、2．90×10^-4mg／L、4．76×10^-4mg／L．将该方法应用于实际人血清样品中总蛋白的测定,结果与考马斯亮蓝法比较,令人满意．     

人血清中总蛋白的四羧基铁酞菁二级散射法测定

在pH3.8的Britton-Robinson (B-R)缓冲溶液中,蛋白质与四羧基铁(Ⅲ)酞菁(Fe(Ⅲ)Pc (COOH)4)结合,使二级散射信号ISOS增强,且增强的二级散射信号与蛋白质浓度呈良好的线性关系.在最大的二级散射波长(λSOSmax)处分别对牛血清白蛋白(BSA)、人血清白蛋白(HSA)、人免疫球蛋白(IgG)、α-糜蛋白酶(α-Chy)进行测定,线性范围分别为0.0～1.80mg/L、0.0～1.60 mg/L、0.03～1.20mg/L、0.0～1.20mg/L;相应检出限分别为0.501、0.354、3.63、1.18μg/L.将该方法应用于实际人血清样品中总蛋白的测定,结果与考马斯亮蓝法基本一致.     

钙试剂-蛋白质体系的共振光散射光谱研究

基于蛋白质对钙试剂共振光散射的增强作用,拟定了一种测定蛋白质的共振光散射法。在pH 4.00的水溶液中,钙试剂在595 nm处的共振光散射增强与蛋白质浓度呈线性关系。此方法对人血清白蛋白、牛血清白蛋白的检出限分别可达0.068和0.085μg/mL。同时得到钙试剂与人血清白蛋白和牛血清白蛋白的结合常数(K)以及结合位点数(n)分别为8.15×104mol/L,0.18和7.67×104mol/L,1.5。     

甲苯咪唑共振散射法用于蛋白质的痕量检测

建立了血液中痕量蛋白的共振散射(RLS)光谱分析方法。盐酸-甲苯咪唑(MEB)-牛血清白蛋白(BSA)体系的最大共振散射(RLS),二级散射(SOS),倍频散射(FDS)波长分别位于296、500和340nm。3种散射增强(ΔI)在一定范围内与蛋白质浓度成正比,方法线性范围分别是RLS为0.4～2.0 mg/L、SOS为0.4～2.4 mg/L;FDS为0.4～2.0 mg/L;检出限分别为1.059(RLS)、1.324(SOS)、4.743μg/L(FDS)。方法可用于血清中蛋白质的测定,回收率在97.9%～104.6%之间。     

酸性铬兰K-OP-牛血清白蛋白体系的共振瑞利散射及共振非线性散射光谱研究及应用

在pH 3.2的邻苯二甲酸氢钾-HCl缓冲液中,酸性铬兰K(ACBK)-OP与牛血清白蛋白(BSA)形成三元离子缔合物,导致共振瑞利散射(RRS)、二级散射(SOS)和倍频散射(FDS)的显著增强,光谱最大散射波长分别位于420,678和340nm。体系的光散射强度与BSA浓度在一定范围内呈线性增强,RRS在0~3.5 mg/L,SOS在0~3 mg/L,FDS在0~3 mg/L范围内对BSA的检出限分别为0.3,0.7和0.8μg/L,据此建立了测定BSA的共振线性(RRS)和共振非线性光散射(RNLS)分析法。以RRS法考察了酸性铬兰K-OP与白蛋白形成三元缔合物的适宜条件、影响因素等。方法可用于合成样品及血清样品中蛋白含量的测定。     

天青A-BSA共振散射光谱研究及分析应用

考察了天青A与牛血清白蛋白(BSA)混合体系的共振散射光谱,发现天青A的加入能引起BSA的共振散射光谱强度明显增强,通过优化实验条件建立了测定蛋白的新方法.在p H=3.78的磷酸氢二钠-柠檬酸缓冲溶液中,固定天青A浓度为1.00×10-5mol/L,当牛血清白蛋白浓度在8.80×10-8~4.40×10-6mol/L范围内与体系的共振光散射强度值呈良好的线性关系,线性方程为IRLS=69.744c(mol/L)+59.359,相关系数r=0.992 8,检出限为3.28×10-8mol/L,方法应用于牛尿样品中白蛋白含量的测定,回收率在97%~106%之间,表明方法具有较高的准确度,结果令人满意.     

溴百里酚蓝-蛋白质体系的共振瑞利散射光谱的研究及分析应用

基于蛋白质对溴百里酚蓝共振瑞利散射的增强作用,建立了一种测定蛋白质的方法.在酸性B-R缓冲溶液中,溴百里酚蓝在365 nm波长处的共振光散射增强与蛋白质浓度呈线性关系.对人血清白蛋白、牛血清白蛋白、γ-人球蛋白、卵白蛋白测定的线性范围分别为0.04～2.4,0.04～2.4,0.04～1.6,0.04～1.8 mg·L-1;相应的检出限分别为23.9,23.O,25.0,30.4μg·L-1.用于人血清、尿液中总蛋白质含量的测定,分析结果的RSD依次为1.5%和3.3%,且与考马斯亮蓝法的结果相符.     

同多酸和染料探针共振光散射法测定蛋白质

在酸性条件下,铬黑T、钼酸铵与蛋白质形成聚合物,使体系的共振光散射明显增强。据此建立了利用共振光散射技术测定总蛋白含量的新方法。在最佳条件下,体系的最大散射峰位于555nm处。共振光散射增强的程度与蛋白质的浓度呈良好的线性关系。牛血清白蛋白和人血清白蛋白的线性范围分别为0.20～10.0μg/mL和0.10～8.0μg/mL,检出限为0.050μg/mL和0.039μg/mL。方法已用于人血清样品的分析,并与考马斯亮蓝的测定结果进行了比较,两者无显著性差异。     

钍试剂Ⅱ与蛋白质作用的共振光散射特征及微量蛋白质的光散射测定

研究了钍试剂Ⅱ与蛋白质在pH 4 3条件下作用的共振光散射特征 ,并以此建立了测定微量蛋白质的新方法。用普通荧光分光光度计测量了这一体系的共振光散射光谱 ,考察了影响因素。在最佳实验条件下 ,牛血清白蛋白 (BSA)浓度在 0mg/L～ 1 0 0mg/L范围内成线性关系。方法已用于尿中微量蛋白质的测定     

茜素绿-蛋白质体系的共振瑞利散射光谱及其分析应用

基于蛋白质对茜素绿共振瑞利散射的增强作用,建立了一种测定水溶性蛋白质的新方法.在酸性BR缓冲溶液中,茜素绿在365 nm处的共振光散射增强与蛋白质浓度呈线性关系.对人血清白蛋白、牛血清白蛋白、γ-人球蛋白、卵白蛋白测定的检出限均低于14 ng/mL.该方法灵敏、稳定、选择性好,适用于人血清、尿液中总蛋白质的测定.     

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.