甲基环戊二烯基水杨酸钛(Ⅳ)配合物的合成与表征

采用不相法和两相法用二氯二甲茂钛与相应的水杨酸反应合成了6个配合物：二甲基环戊二烯基水杨酸钛（I），二甲基环戊二烯基二水杨酸钛（Ⅱ），二甲基环戊二烯基-5硝基水杨酸钛（Ⅲ），二甲基环戊二烯基二5-硝基水杨酸钛（IV），二甲基环戊二烯基3，5-二硝基水杨酸钛（V），二甲基环戊二烯硫代水杨酸钛（VI），对这些化合物进行了元素分析，测定了熔点，计论了它们的红外光谱和核磁共振谱。     

5—氨基水杨酸锌及相关物质的高效毛细管电泳分离与测定

１引言５－氨基水杨酸是治疗胃溃疡和Ｃｒｏｈｎ疾病的药物。为提高稳定性和药物疗效，最近合成了新药物５－氨基水杨酸锌。我们对５－氨基水杨酸锌与主要杂质水杨酸，以及可能降解产物５－氢基水杨酸与对氨基苯酚等物质的高效毛细管电泳（ＨＰＣＥ）的分离与测定进行了研究，结果表明，本法分离效果好，测定准确，具有较好的应用价值。２实验部分１２２９ＨＰＣＥＡＮＡＬＹＳＥＲ（北京新技术应用研究所），石英毛细管（６５．５ｃｍ×５０μｍｉ．ｄ，有效长度５７．３ｃｍ，河北永年光纤厂）。５－氨基水杨酸锌（ＺｎＡＳＡ，９９％），…     

高效液相色谱同时测定乙酰水杨酸散中的乙酰水杨酸和水杨酸

１引言乙酰水杨酸散系解热镇痛药，其有效成份为乙酰水杨酸，所含的水杨酸是杂质。卫生部标准ＷＳ－０５９（ｘ－０４６）－９５（试行）系采用甲醇－冰乙酸为溶剂浸取样品中的乙酰水杨酸和水杨酸，然后用ＨＰＬＣ外标法同时测定。但乙酰水杨酸在这种溶剂中易分解生成水杨酸，使水杨酸的测定结果偏高。本文在该产品的部颁标准基础上，改用乙醇－氯乙酸作溶剂，有效地抑制了乙酰水杨酸的分解，采用超声波浸取法，使待测物被完全浸取，通过内标物的采用和检测波长的选择，使测定的准确度和精密度得到显著改善。２实验部分２．１仪器及试剂日本…     

[Cu(Hsal)2(py)2]n晶体结构和二维堆积网络

０引言水杨酸具有羧基和羟基，是双功能基配体，羧基和羟基可分别脱去氢，因此有多种形式可参与配位（见Scheme１），其中Hsal－１的形式仅见一例报道犤１犦，其可靠性有待更多的研究来确证。对铜／水杨酸／吡啶三元体系的研究已有多篇文献报道犤２～４犦，亦有几种化合物合成，例如Cu（Hsal）２（py）２和Cu（sal）（py）２等。配合物Cu（sal）（py）２的可靠性值得怀疑，原文中无合成和表征犤３犦。铜／水杨酸／吡啶衍生物三元体系已有多个晶体结构报道犤５，６犦，但迄今无铜／水杨酸／吡啶三元体系晶体结构报道。对于配合物Cu（Hsal…     

双环戊二烯基钛衍生物的水相化学及双环戊二烯基二水扬酸钛的晶体结构

（ＲＣｐ）２ＴｉＣｌ２的乙酰丙酮体系在水相中与硫氰酸钾，吡咯烷基二硫代氨基甲酸钠，取代苯甲酸钠等反应，合成得到相应的（单）双环戊二烯基（或甲基环戊二烯基）钛衍生物，双环戊二烯基二水杨酸钛单晶的结构分析表明，水杨酸作为单齿配体通过羧基氧原子与钛键联。     

双环戊二烯基钛衍生物的水相化学及双环戊二烯基二水杨酸钛的晶体结构

（ＫＣｎ）２ＴｉＣｌ２的乙酰丙酮体系在水相中与硫氰酸钾、吡咯烷基二硫代氨基甲酸钠、取代苯甲酸钠等反应，合成得到相应的（单）双环戊二烯基（或甲基环戊二烯基）钛衍生物。双环戊二烯基二水杨酸钛单晶的结构分析表明，水杨酸作为单齿配体通过梭基氧原子与钛键联。     

水杨酸烃基二甲硅基甲酯的合成及其生物活性

以三甲基氯硅烷，烃基溴化镁和水杨酸为原料，经氯化，格氏反应，亲核取代和脱氯化钠等步骤，合成了一类新型的植物生长调节剂－水杨酸烃基二甲硅基甲酯（ＣＯ２ＣＨ２Ｓｉ（Ｒ）（ＣＨ３）２，ＯＨＲ＝Ｃ２Ｈ６，Ｃ３Ｈ７，Ｃ４Ｈ９，Ｃ６Ｈ５和Ｃ６Ｈ５ＦＨ２）其结构经元素分析，ＩＲ和＾１ＨＮＭＲ证实，对四季桔的初步生物活性试验表明，有机硅基引主水杨酸分子中后，对桔桔的保花保果效果比母体化合物的更好。     

壳聚糖-g-水杨酸的合成

合成了壳聚糖-g-水杨酸,用1^H NMR,IR和热重分析等对结构进行了表征。接枝反应的最佳条件为：壳聚糖12．5mmol,n（水杨酸）：n（壳聚糖）=0．75,于55℃～65℃反应1h,水杨酸接枝率为20％。     

Br(o)nsted酸性离子液体催化合成阿司匹林

用Brcnsted酸性离子液体[Hmim]BF4、[bmim]HSO4和[bmim]H2PO4代替浓H2SO4为催化剂催化乙酸酐对水杨酸的乙酰化，合成阿司匹林。考察了反应温度、反应时间、催化剂用量、酐／醇摩尔比对水杨酸酰化反应产率的影响和离子液体的重复使用性能。选择了最佳反应条件，以[bmim]H2PO4作为催化剂，催化剂用量为0．28g（1．18×10^-3mol），水杨酸2．762g（0．02mol），乙酸酐4．083g（0．04mol），n（酐）：n（醇）=2：1，反应时间30min，反应温度70℃，产率最高达63．43％，并且[bmim]H2PO4溶于水后通过过滤和旋蒸脱水，重复使用3次，产率无明显变化。     

天然铜－锌超氧化物歧化酶的电化学行为的研究

天然铜－锌超氧化物歧化酶的电化学行为的研究韩吉林，陈洪渊，钱雯，金生浩（南京大学化学系，南京，２１００９３）（南京医科大学）关键词铜－锌超氧化物歧化酶，极谱法，伏安法超氧化物歧化酶（ＳＯＤ）是一种广泛存在于生物体内的金属酶，它能够催化超氧阴离子自由基...     

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.     

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.     

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.     

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.