聚氯乙烯膜氧氟沙星和曲马多选择电极的研制与应用

报道了以氧氟沙星碘化物与碘化铋的分子缔合物为电活性物的新型聚氯乙烯膜氧氟沙星选择电极。并以类似的方法报道了曲马多选择电极。氧氟沙星电极的特响应范围为１．０×１０＾－２－２．２×１０＾－５ｍｏｌ／Ｌ，斜率为３０ｍＶ／ＰＣ，检测限为１．６×１０＾－５ｍｏｌ／Ｌ。     

苯骈三唑阴离子选择性电极的研制

本报道了一种以乙基紫－苯骈三唑阴离子缔合物为活性物的ＰＶＣ基质碳棒涂膜式ＢＴＡ阴离子选择性电极的研制及其电位响应特性。在２５℃时，电极的线性响应范围５×１０＾－５－１×１０＾－２ｍｏｌ／Ｌ，检测限１．１×１０＾－５ｍｏｌ／Ｌ，响应斜率５８ｍＶ。     

洛美沙星离子选择电极的研制及应用

用正交设计法研究了离子缔合物的种类,膜相中活性物浓度和增塑剂３个因素对电极性能的影响,以四苯硼－洛美沙星形成的缔合物为电活性物质研制了涂碳ＰＶＣ膜洛美沙星电极。其能斯特响应范围为２．０×１０＾－３－１．０×１０＾－５ｍｏｌ／Ｌ;检测限为４．０×１０＾－６ｍｏｌ／Ｌ,级差为２８．９ｍＶ／ｐＣ。     

乙醇酸菠菜组织电极和马兰组织电极的研究

分别以菠菜和马兰叶为生物催化材料，将其叶浆组织与氧电极相结合，首次制成乙醇酸电极，本研究了这两种电极的响应性能。菠菜组织电极线性范围为５．０×１０＾－６－１．０＾１０＾－４ｍｏｌ／Ｌ；响应时间为３ｍｉｎ；寿命为１０天，马兰组织电极线性范围为２．０×１０＾－６－１．０×１０＾－４ｍｏｌ／Ｌ；响应时间为３ｍｉｎ；寿命至少３０天。这两种电极对底物乙醇酸钠皆有良好的选择性。     

聚氯乙烯膜奎宁选择电极的研制与应用

本报道了一种以奎宁溴汞酸盐为电活性物的ＰＶＣ膜奎宁选择电极，其线性响应范围为１．０×１０＾－２－１．０×１０＾－６ｍｏｌ／Ｌ；级差５８±１ｍＶ；检测限为８．２×１０＾－７ｍｏｌ／Ｌ。以此电极测定奎宁的含量，方法简单、快速、结果与药典法相符。     

铁的单点络合滴定法研究

本研究了Ｆｅ＾３＋的单点络合滴定法，导出了定量关系式，比较了以铂电极为指示电极和以ＰＶＣ膜四氯络铁（Ⅲ）阴离子电极为指示电极时电位测量的稳定性及所得的分析结果。在Ｆｅ＾３＋浓度为１．０００×１０＾－３ｍｏｌ／Ｌ时，１８次实验的平均值为１．０２×１０＾－４ｍｏｌ／Ｌ，相对偏差小于１．７％；Ｆｅ＾３＋在５．０×１０＾３ｍｏｌ／Ｌ以上时，相对偏差小于０．１％；其浓度小于１０＾－３ｍｏｌ／Ｌ而大于５×１     

苄氧基甲基12—冠—3的合成与锂离子选择性电极研究

报道了苄氧基甲基－１２－冠－３－的合成，并以此化合物作载体研制成锂离子选择电极。用苄氧基甲基－１２冠－３－为载体的电极对锂离子响应拇性范围为１．０×１０＾－１－８．３×１０＾－５ｍｏｌ／Ｌ．检测限为４．２×１０＾－５ｍｏｌ／Ｌ，斜率为５７．４ｍＶ／ｐＬｉ。电极具有好的稳定性和重现性。     

盐酸氟桂嗪离子选择性电极的制备及应用

研制了盐酸氟桂嗪离子选择性电极。利用正交设计法综合研究了活性的类型、含量以及增塑剂等因素对ＰＶＣ膜电极响应性能的影响，结果表明，以盐酸氟桂嗪－四苯硼钠离子缔合物为活性物质，ＤＢＰ或ＤＯＰ为增塑剂制成的ＰＶＣ膜电极的性能最佳。其响应范围为１．０×１０＾－４－５．０×１０＾－３ｍｏｌ／Ｌ，检测下限为３．５×１０＾５ｍｏｌ／Ｌ，响应斜率为５８ｍＶ（２５℃）。应用该电极对合成样品及胶囊样品中盐酸氟桂嗪含量     

L—天冬门酰胺微生物电极的研制

以谷氨酸棒状杆菌作为生物催化剂，与基础氨气敏电极结合制成对Ｌ－天冬门酰胺响应的微生物电极，在３０℃时选择ＰＨ＝８．５的硼酸缓冲体系，测得电极的线性范围为７．１×１０＾－５－１．１×１０＾－２ｍｏｌ／Ｌ，斜率为５１．４ｍＶ／ｄｅｃ，检测下限为２．０×１０＾－５ｍｏｌ／Ｌ，响应时间为４－７ｍｉｎ寿命达３０ｄ以上。     

葡萄糖氧化酶共价交联于蛋膜上的葡萄糖传感器

以牛血清白蛋白－戊二醛为交联剂，将葡萄糖氧化酶固定地鸡蛋膜上，氧电极作电化学敏感元件，制成葡萄糖氧化酶电极。传感器的响应范围为４．０×１０＾－６－２．４×１０＾－３ｍｏｌ／Ｌ；检测限为１．２１０＾－６ｍｏｌ／Ｌ。该传感器具有线性范围宽，灵敏度高，使用寿命长等优点。     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

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%).     

Selective synthesis of 4,5-dihydroimidazo- and imidazo[1,5-a]quinoxalines via modified Pictet–Spengler reaction

An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction.     

Understanding the Diels-Alder reactivity of 1,2-azaborine analogues

The Diels-Alder reactivity of 1,2-heteroborines (H₄C₄B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.     

Synthesis of N-substituted carbazolones from α-iodo enaminones via Pd(0)-catalyzed intramolecular coupling under microwave irradiation

A variety of N-aryl and N-alkyl carbazolones were conveniently achieved in good to high yields via Pd₂(dba)₃-mediated intramolecular coupling of N-substituted α-iodo enaminones under microwave irradiation. The Pd(0)-catalyzed cyclization was found to proceed favorably with the more electron-deficient phenyl ring during the reactions involving unsymmetrical N,N-diaryl α-iodo enaminones. This unique property enables the construction of carbazolone skeleton containing nitro substituted benzenoid ring.     

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 substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles by intramolecular nitrilimine cycloaddition

Both substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles have been synthesized by the 3+2 intramolecular dipolar cycloaddition of nitrilimines to alkynes. This cyclization has been extended to more versatile 3-bromo derivatives by the use of alkynylbromides as dipolarophiles.