铜(Ⅱ)-黄原酸配合物微粒体系的光谱研究及其在废水分析中的应用

采用分光光度法和共振散射光谱法研究了Cu(Ⅱ)-黄原酸配合物微粒体系。该配合物微粒体系在410nm处有一吸收峰,其吸光度与黄原酸浓度在1.0～40×10-5mol/L范围成良好线性关系,检出限(3σ)为0.5×10-5mol/L。据此建立了一个测定废水中黄原酸含量的分光光度法.该法灵敏、简便、快速、准确、重复性好,平均回收率为98%～100%,相对标准偏差RSD为0.9%～1.9%.共振散射光谱研究结果表明,该体系存在Cu(Ⅱ)-黄原酸配合物微粒,该微粒在360nm处存在共振散射效应.     

铜磷钼酸分光光度法间接测定盐酸羟胺

在pH3．0的Clauk-Lubs缓冲溶液中,基于盐酸羟胺能定量地将铜磷钼杂多酸还原为铜磷钼蓝的现象,建立了分光光度法间接测定盐酸羟胺的方法。结果表明,测定的线性范围是0～7．68μg／mL,相关系数r=0．9996,RSD为0．43％(n=6)。方法简便快捷,准确可靠。用于工业盐酸羟胺的测定,结果满意。     

磷钼杂多酸-罗丹明S体系的共振散射光谱研究

在0.14mol·dm^-^3H~2SO~4介质中,PO~4^3^-,MoO~4^2^-与罗丹明S形成磷钼杂多酸-罗丹明S三元缔合物,在610nm处产生一灵敏的共振散射(即瑞利散射)光谱峰,磷浓度在0.2～20μg·dm^-^3范围内与共振散射光强度呈良好线性关系。实验结果表明,本法具有灵敏度高、选择性好等特点,用于水和茶叶试样中磷酸根的测定,结果与示波极谱法的测定结果一致。     

微肥中锌的双硫腙螯合微粒共振散射光谱分析

在pH9．0的NH3—NH3-Cl缓冲溶液中,Zn(Ⅱ)与双硫腙可形成能稳定存在的螯合物微粒,显示出共振散射效应．该微粒体系的最强共振散射峰在605nm处,锌的浓度在0．02～1．54μg／mL范围内与共振散射强度(J605nm)呈线性关系,检出限为0．008μg／mL Zn．利用共振散射测量微肥中微量元素锌,方法简单、灵敏度高、重现性好,结果满意。     

纳米金共振散射光谱法测定痕量乐果

在H2SO4介质中,有机磷乐果和钼酸钠、酒石酸锑钾反应,生成淡黄色的有机磷锑钼三元杂多酸,纳米金在726 nm处产生一个较强的共振散射峰。抗坏血酸可将该有机磷锑钼杂多酸还原为有机磷锑钼杂多蓝,导致726 nm处共振散射峰的强度降低。乐果质量浓度在0.014～1.66μg/mL范围内与共振散射光强度降低值ΔI呈良好的线性关系,其回归方程为ΔI=155.4ρ+1.4,相关系数为0.9970,方法的检出限为3.9 ng/mL,该法可用于废水中乐果的测定。     

砷(Ⅴ)—钼酸铵—碘绿的共振瑞利散射光谱及其应用研究

研究了砷(Ⅴ)-钼酸铵-碘绿体系的共振瑞利散射光谱特性。在硫酸介质中,砷(Ⅴ)与钼酸反应生成砷钼杂多酸大阴离子,其与阳离子染料碘绿结合形成离子缔合配合物,导致体系共振瑞利散射光剧烈增强,据此建立了共振瑞利散射分析法测定砷(Ⅴ)的新方法。方法的线性范围为0.01~0.40μg/mL,检出限1.5μg/L。RSD为2.55%、1.86%,样品加标回收率为95.5%~104.3%。该法简便快速,用于测定化妆品中微量砷,结果满意。     

过氧化氢氧化硫酸耐尔蓝催化褪色光度法测定痕量硅

测定痕量硅的方法有硅钼蓝光度法、间接原子吸收光谱法、硅钼蓝杂多酸极谱法、流动注射示差动力学化学发光法、硅钼蓝．罗丹明B离子缔合物分光光度法、阻抑．褪色光度法、硅锑钼杂多酸．罗丹明B四元络合体系光度法、乙基罗丹明B-硅钼杂多酸．PVA光度法、乙基罗丹明B-硅钼杂多酸．阿拉伯树胶体系分光光度法及停流流动注射化学发光法,未见     

盐酸小檗碱-十二烷基苯磺酸钠缔合微粒体系的共振散射光谱研究及其分析应用

在pH 4 .80NaAc HAc缓冲介质中 ,盐酸小檗碱 (BH)与十二烷基苯磺酸钠 (DBS)由于静电引力和疏水作用力形成缔合微粒 ,在 4 70nm处有一共振散射峰。随着DBS浓度增大 ,该峰急剧增强 ,即存在缔合微粒的散射光增强效应 ;345nm处的吸光度减弱 ,即存在缔合微粒的减色效应。研究了共振散射光谱测定BH的影响因素 ,提出了测定 (0 .35～ 4 .4 )× 10 -5mol/L盐酸小檗碱的共振散射光谱新方法 ,用于复方黄连素片剂和针剂样品的测定 ,结果满意     

小檗碱-I－3缔合微粒体系的光度分析应用

在稀HCl介质中,I-3在340 nm处有一吸收峰;当小檗碱(BB)与I-3共存时体系呈橙黄色,在580 nm处产生一共振散射峰.以试剂作参比,该缔合微粒体系在530 nm产生一吸收峰,BB浓度在0～7.0×10-5mol/L范围内与A530 nm呈线性,据此建立了一种测定小檗碱含量的分光光度新方法,并用于针剂样品中小檗碱测定,结果满意.同步散射光谱研究表明,BB+与I-3可通过静电引力作用形成疏水性的(I3-BB)缔合物分子,并进一步聚集形成稳定的(I3-BB)n缔合纳米微粒.由于该缔合纳米微粒在580 nm处产生共振散射效应,故体系呈橙黄色.     

盐酸苯海拉明-硅钨酸缔合微粒体系的光谱研究及分析应用

盐酸苯海拉明-硅钨酸缔合微粒体系的光谱研究及分析应用;盐酸苯海拉明;硅钨杂多酸;缔合微粒;分光光度法;共振散射     

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.