流动注射化学发光法测定头孢克洛

研究发现在碱性条件下,头孢克洛对Luminol-H2O2体系的化学发光有较强的增敏作用,据此建立了流动注射化学发光测定头孢克洛药物的新方法。头孢克洛在1.0×10-8~2.0×10-5g/mL范围内与发光信号的增强值(ΔI)呈良好的线性关系;检出限(3δ)为6.0×10-9g/mL;对于1.0×10-6g/mL头孢克洛进行11次测定,相对标准偏差为2.2%。应用于希刻劳颗粒中头孢克洛的测定。     

Ce(Ⅳ)-罗丹明6G化学发光体系与毛细管电泳联用同时测定氯丙嗪和异丙嗪

提出了一种毛细管电泳化学发光联用技术同时测定氯丙嗪和异丙嗪。在酸性条件下,氯丙嗪和异丙嗪能被Ce(Ⅳ)氧化,然后将能量转移给荧光发射体-罗丹明6G,并以化学发光形式释放能量。基于此,结合流动注射技术,以10 mmol/L KH2PO4/H3PO4(pH3.5)为运行缓冲液,实现了两种药物的分离。方法的线性范围分别为4.0×10-8~2.0×10-6g/mL和2.0×10-8~2.0×10-6g/mL,检出限分别为5.6 ng/mL和3.4 ng/mL,对2.0×10-6g/mL异丙嗪平行测定了9次,相对标准偏差为2.8%。方法可用于同时测定人血清中的氯丙嗪和异丙嗪。     

MnO_2纳米溶胶-抗坏血酸化学发光反应的研究

在中性条件下利用Na2S2O3还原KMnO4制备出平均粒径约40 nmMnO2溶胶。研究发现,该溶胶在酸性条件下可氧化抗坏血酸产生化学发光。基于此,结合流动注射技术,对影响化学发光反应的各种因素进行了考察,建立了测定抗坏血酸的流动注射化学发光新方法。该方法测定抗坏血酸的线性范围为2.0×10-6~1.0×10-4g/mL,检出限为4×10-7g/mL,相对标准偏差为2.1%(1.0×10-5g/mL抗坏血酸溶液,n=11)。该方法已用于片剂中抗坏血酸的测定,结果与药典方法一致。     

流动注射化学发光法测定氯化血红素

在甲醛存在的条件下,在酸性溶液中KMnO4与氯化血红素能够发生化学发光反应,产生很强的化学发光。据此采用流动注射技术,建立了一种利用KMnO4-甲醛-氯化血红素化学发光体系测定氯化血红素的化学发光分析法。方法的检出限为6×10-8g/mL;相对标准偏差为1.8%(2.0×10-6g/mL氯化血红素,n=11);线性范围为2.0×10-7~8.0×10-6g/mL。本法用于新鲜鸡血中氯化血红素的测定,结果与标准方法测得值一致。并对化学发光反应的机理进行了探讨。     

K3Fe(CN)6-钙黄绿素体系后化学发光反应测定盐酸氯丙嗪

发现了盐酸氯丙嗪在K3Fe(CN)6-钙黄绿素化学发光反应体系中的后化学发光反应,优化了反应条件,建立了一种利用后化学发光反应测定盐酸氯丙嗪的流动注射化学发光分析法.方法的检出限为3×10-8/mL,相对标准偏差为2.0%(2.0×10-6 g/mL盐酸氯丙嗪,n=11),线性范围为1.0×10-7～1.0×10-5 g/mL.此法已用于盐酸氯丙嗪片剂中盐酸氯丙嗪含量的测定,结果与药典方法测定值一致.     

流动注射化学发光法测定阿莫西林

在碱性介质中,铁氰化钾能够氧化阿莫西林产生微弱的化学发光,Na2SO3对该体系有较强的增敏作用,据此,结合流动注射技术,建立了测定阿莫西林的新方法.阿莫西林在5.0×10-8～2.0×10-5 g/mL范围内与化学发光强度呈良好的线性关系,检出限为3×10-8 g/mL,对2.0×10-6 g/mL的阿莫西林进行11次平行测定,相对标准偏差为1.5%.本法已用于胶囊中阿莫西林的测定,并初步探讨了该化学发光反应的机理.     

化学发光法测定去羟肌苷

建立了快速检测去羟肌苷的化学发光方法。在HNO3介质中,去羟肌苷对KMnO4-Na2SO3化学发光体系有较强的抑制作用,且抑制的程度与去羟肌苷的质量浓度在一定范围内呈良好的线性关系,据此可以测定去羟肌苷含量。方法的线性范围为4.0×10-7~1.0×10-4g/mL,检出限为9.6×10-8g/mL。对8.0×10-5g/mL去羟肌苷测定的相对标准偏差为2.0%(n=11)。方法适用于胶囊中去羟肌苷的含量测定。     

纳米金催化鲁米诺化学发光体系测定甲巯咪唑

在碱性介质中,甲巯咪唑能强烈增敏纳米金-鲁米诺-硝酸银化学发光体系产生较强的化学发光信号,据此建立了一种流动注射化学发光测定甲巯咪唑的新方法。在优化实验条件下,该方法对甲巯咪唑的检测线性范围为1.0×10-9~1.0×10-8、1.0×10-8~1.0×10-7、1.0×10-7~1.0×10-6g/mL,检出限(S/N=3)为3.0×10-10g/mL,相对标准偏差为1.2%(n=11,ρ=1.0×10-8g/mL)。将该法用于药物中甲巯咪唑含量的测定,结果满意。同时,采用化学发光光谱表征技术对该体系的化学发光反应机理进行了初步探讨。     

流动注射-化学发光法测定盐酸多巴酚丁胺

在磷酸介质中,利用高碘酸钠一过氧化氢-盐酸多巴酚丁胺化学发光体系,结合流动注射技术,建立了一种测定盐酸多巴酚丁胺含量的化学发光新方法。方法的线性范围为2.0×10~(-9)～1.0×10~(-6)g/mL,检出限为2.7×10~(-9)g/mL。测定结果的相对标准偏差为1.6％～2.1％,回收率为93.7％～97.7％。     

反相流动注射化学发光法测定甲硝唑

在硫酸介质中,高锰酸钾氧化鲁米诺产生化学发光,甲硝唑对该体系有一定的抑制作用。据此,建立了反相流动注射化学发光法测定甲硝唑的新方法。甲硝唑浓度在1.4×10-3~2.0×10-2mg/mL范围内,相对化学发光强度△I与甲硝唑含量的对数呈良好的线性关系;方法的检出限(3σ)为1.0×10-3mg/mL;相对标准偏差(c=0.02mg/mL,n=11)为1.8%。本法应用于片剂中甲硝唑含量的测定,结果满意。     

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.