包头市青山区8～10岁儿童碘缺乏病甲状腺肿大率及尿碘监测分析

调查了内蒙古青山区８～１０岁儿童碘缺乏病甲状腺肿大率，结果表明，甲状腺肿大率为１９．６％，且以城乡结合部居住儿童为高，监测了其尿碘，尿碘水平１００μｇ／Ｌ以下者为１１．２％，其中５０μｇ／Ｌ者了有发现，据此情况，今后仍要强化防治工作。     

增敏荧光光谱法测定复方新诺明中的磺胺甲(口恶)唑

提出了在溴化十六烷基三甲铵（ＣＴＡＢ）存在下,ＰＨ为４．０的ＨＡｃ－ＮａＡｃ缓冲溶液中,增敏荧光光谱法测定复方新诺明中磺胺甲恶唑（ＳＭＺ）含量的新方法。碘胺甲恶唑浓度在０．０８－０．８μｇ／ｍＬ范围内,荧光强度与碘胺甲恶唑浓度呈良好的一性关系。方法的检出限为０．０１６μｇ／ｍＬ（６．３２＊１０＾－８ｍｏｌ／Ｌ）。方法已用于测定复方新诺明中磺胺甲恶唑的含量。     

倒数示波计时电位法同时测定粮食中Cu、Pb含量

在分别含有２ｇ／Ｌ乙二胺与＊１０＾－４ｍｏｌ／Ｌ８－羟基喹啉（Ｏｘｉｎｅ）和０．３ｍｏｌ／Ｌ的氢氧化钠淀粉液中,Ｃｕ＾２＋、Ｐｂ＾２＋具有良好的示波图。其切口电位分别为－０．８５Ｖ,－１２０Ｖ（ｖｓ．ＳＣＥ）,二者相差０．３５Ｖ,能够分辨,可同时测定,本方法应用于大米中Ｃｕ、Ｐｂ含量的同时测定,检出限分别为５．８μｇ／Ｌ（Ｃｕ）、１０．０μｇ／Ｌ（Ｐｂ）,平均回收率为９６．０％、１０２．０％。     

下基罗丹明B—高磺酸钾动力学光度法测定锗

报道了以锗催化高碘酸钾氧化丁基罗丹明Ｂ为基础的动力学测定痕量铑的方法,详细研究了动力学条件,建立了动力学光度测定痕量铑的新方法。铑浓度在０－１８０μｇ／Ｌ范围内与ｌｏｇ呈线性关系,检出限为２．８４×１０＾－７ｇ／Ｌ,该反应对Ｒｈ或丁基罗丹明Ｂ为为一级反应,表观活化能为６４．０４ｋＪ／ｍｏｌ。本方法用于某些催化剂中铑的测定,其相对标准偏差为１．７６－３．４６％,回收率为９６．８－１０４．７％。     

丁基罗丹明B—钼酸盐光度法连续测定铈和钪

在聚乙烯醇（ＰＶＡ）存在下，丁基罗丹明Ｂ（ＢＲＢ）分别与铈钼、钪钼杂多酸络阴离子形成离子缔合物，其最大吸收均位于５７０ｎｍ，表面摩尔吸光度分别为εＣｅ＝３．９６×１０＾６Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，εＳｃ＝４．７１×１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，服从比耳定律范围分别为０－２４μｇ／Ｌ Ｃｅ和０－６０μｇ／ＬＳｃ，测定极限为Ｃｅ１．０μｇ／Ｌ（ｎ＝１２）和Ｓｃ１．９μｇ／Ｌ（ｎ＝１０），对     

差示分光光度法测定药物制剂中的四环素

提出了四环素与钴离子络合反应测定四环素的新方法,线性范围为０．８－２５μｇ／ｍＬ,ε＝１．３３＊１０＾４Ｌ．ｍｏｌ＾－１．ｃｍ＾－１,回收率为９７．８％－１０１．５％。方法已用于制剂中四环素的测定。     

火焰原子吸收法测定植物样品中硼与碘

将ＢＯ＾３－３转化为ＢＦ＾－４，ＩＯ＾－３转化为Ｉ＾－以Ｃｄ（ｐｈｅｎ）＾２＋３络合和硝基苯萃取，用火焰原子吸收法间接测定与碘，其特征浓度达０．０１６μｇ／ｍＬ１％Ａ和０．０２８μｇ／ｍＬ１％Ａ，在稻米等样品中作加标回收，硼回收率为９２．８－１０２．４％，碘为９７．２－１０６．７％。     

4,5—二溴苯基荧光酮光度法测定钇

研究４，５－二溴苯基荧光酮灵敏光度法测定钇。在ｐＨ５．５缓冲溶液中钇与ＤＢＰＥ形成橙红色络合物，最大吸收波长位于５５０ｎｍ，表观摩吸光系ε值１．５３×１０＾５Ｌ．ｍｏｌ＾－１．ｃｍ＾－１，钇量在每２５ｍＬ０－８μｈ范围内服从比耳定律，测定极限６．８μｇ／Ｌ，对于钇０．２４ｍｇ／Ｌ测定的相对标准偏差为２．６％，络合物的摩尔组成为Ｙ：ＤＢＰＦ＝１：３。方法用于镁合金和地质标样中钇的测定，结果满意。     

襄樊市区1235名孕妇尿碘含量监测分析

对襄樊市区孕妇尿碘含量进行了监测。监测结果：尿碘低于１００μｇ／Ｌ者，３０岁以上年龄组为高，达４８．３９％，９－１１月季节组为高，达４４．３５％；７个月以上的孕期组为高，达３０．６４％，农民缺磺情况远远高于工人（２６．０７％）、干部（２２．３％）、商人（１５．９８％），其尿碘平均含量低于１００μｇ／Ｌ者，高达４０．４５％，为各职业之冠，可见孕妇尿碘含量监测的重点应是病区农民。     

DBM-MSA 光度法测定食品包装材料和容器中的铅

研究了新显色剂二溴对甲基偶氮甲磺（ＤＢＭ－ＭＳＡ）与铅的显色反应,在量浓度为０．２４ｍｏｌ／Ｌ的Ｈ３ＰＯ４介质中,铅在ＤＢＭ－ＭＳＡ形成稳定的蓝色配合物,其组成比为ｎ（Ｐｂ）：ｎ（ＤＢＭ－ＭＳＡ）＝１：２,最大吸收波长为６４２ｎｍ,表观摩尔吸光系数达９．５×１０＾４,铅的质量浓度在０－１５μｇ／２５ｍＬ服从比耳定律,测定量浓度为１０μｇ／２５ｍＬ的铅时大多数金属离子的允许量在ｍｇ级,用于食品包装材     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

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.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

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.