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41.
A number of essential trace elements play a major role in various metabolic pathways and in many diseases like autoimmune, neurological and psychiatric. This study is undertaken with an aim to evaluate the levels of different trace elements in the scalp hair samples of patients suffering from alcohol induced psychosis by particle induced X-ray emission technique (PIXE). It is observed that Fe (p?<?0.0005), Cu (p?<?0.001) are significantly higher in the hair samples of alcohol induced psychosis patients compared to those in normals while concentrations of Mn (p?<?0.005) and Zn (p?<?0.0001) are lower. The concentrations of Co and Ni in the hair samples are found to be in consonance with the concentrations in the normals.  相似文献   
42.
The late-stage functionalization of indole- and tryptophan-containing compounds with reactive moieties facilitates downstream diversification and leads to changes in their biological properties. Here, the synthesis of two hydroxy-bearing allyl pyrophosphates is described. A chemoenzymatic method is demonstrated which uses a promiscuous indole prenyltransferase enzyme to install a dual reactive hydroxy-bearing allyl moiety directly on the indole ring of tryptophan-containing peptides. This is the first report of late-stage indole modifications with this reactive group.  相似文献   
43.
The first organocatalytic approach towards synthesis of rarely explored 1,2,4-selenadiazole and thiadiazole scaffolds have been devised using corresponding carboxamides as substrates. The transformations were realized using two distinct conditions in the presence of catalytic vitamin B3 or thiourea under aerobic conditions. Developed methods overcome the associated limitations of previous reported approaches and the desired products were obtained in high yields and selectivity without the formation of toxic side-products.  相似文献   
44.
Regioselective synthesis of 2-benzoyl-6,6-dimethyl-6,7-dihydrobenzofuran-4(5H)-ones have been accomplished through a novel protocol involving β-amino enone, N-chlorosuccinimide and dimedone in a one pot catalyst-free reaction at an ambient temperature. On the other hand, the same reaction when conducted with two equivalents of N-chlorosuccinimide under similar reaction conditions, exclusive formation of 2-benzoyl-3-(dimethylamino)-6,6-dimethyl-6,7-dihydrobenzofuran-4(5H)-ones were observed. Simple and metal-free reaction conditions, selective product formation and excellent yields are the advantages of this protocol.  相似文献   
45.
Single crystals of Sr(NO3)2, Ba(NO3)2 and Pb(NO3)2 are grown from their aqueous solutions at a constant temperature of 35 °C by slow evaporation technique. Crystals of size 8 to 10 mm along one edge are obtained in a period of 10 days. Chemical etching technique has been employed to study the dislocations in these crystals. The dislocations are randomly distributed and the dislocation density is about 104 to 105 /cm2. Microhardness studies are made on as–grown (111) faces of these crystals upto a load of 100 g. The hardness of the crystals increases with an increase in load and thereafter it becomes independent of the applied load. These results are discussed on the basis of reverse indentation size effect. Meyer index number n for these crystals is estimated at both low and high load regions. An analysis of hardness data of these crystals as well as some other cubic crystals like alums and alkali halates are discussed using Gilman–Chin parameter Hv/C44, where Hv is the microhardness and C44 is the shear constant. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
46.
The synthesis of novel spiro indolinyl isoxazolo[2,3‐c] [1,3,5]thiadiazepinones has been achieved by using one‐pot three‐component domino reaction from 3‐amino‐5‐methylisoxazole, substituted isatins, and mercapto acetic acid by employing p‐toluene sulfonic acid as Lewis acid catalyst. The salient features of the present method are mild reaction conditions, cost effective, environmentally benign, high yields of products and operational simplicity.  相似文献   
47.
Catalyst-free one-pot CN and CC bond formation is described as a simple and ecofriendly method for the synthesis of pyrazole-aniline linked coumarin derivatives. Employing this protocol, a series of derivatives were synthesized in good to excellent yields and tested against different bacterial strains as well as fungal strains. Most of the compounds exhibited potential antimicrobial activity against both Gram-positive and Gram-negative bacterial strains. Among them, the compounds 4b, 4e, 4?h, 4i and 4?k exhibited promising activity on all the tested bacterial strains with values ranging between 1.9 and 7.8?µg/mL. In addition, these compounds were tested against various fungal strains and were found to exhibit potential antifungal activity. Fascinatingly, among the tested derivatives, the compounds 4e, 4?h and 4i were found to be equipotent to miconazole (positive control) against some of the tested fungal strains. Moreover, these compounds showed promising bactericidal, Candida-cidal and biofilm inhibition activities. Further, mechanistic study was carried out with the most active derivative 4i indicated that these compounds inhibit the ergosterol biosynthesis pathway.  相似文献   
48.
近年来,深共熔溶剂热作为一种绿色合成方法被广泛用于多种杂化功能材料的合成。在本研究中,这一合成方法被引入到多核Zr-和Zr/Ti-O纳米团簇的制备,成功获得被邻菲罗啉、苯酚等共轭配体修饰的Zr6以及Ti11Zr4团簇。此方法将为具有精准结构信息的被较多发色团包覆的纳米团簇的合成开辟新的技术路线。此外,光催化分解水产氢实验结果表明,由于具有不同的簇核环境,这两种纳米团簇表现出不同的分散性及与之相关的产氢活性。因此,该研究也为探索金属氧簇材料的结构–性能关系以及结构设计原则提供了借鉴。  相似文献   
49.
This work describes a mild and robust double hydroarylation strategy for the synthesis of symmetrical /unsymmetrical diaryl- and triarylmethanes in excellent yields using Lambert salt (0.2–1.0 mol%). Despite the anticipated challenges associated with controlling selective product formation, unsymmetrical diaryl- and triarylmethanes products are obtained unprecedentedly. A highly efficient gram scale reaction has also been reported (TON for symmetrical product=475 and for unsymmetrical product=390). The synthetic utility of the methodology is demonstrated by the preparation of several unexplored diaryl- and triarylmethane-based biologically relevant molecules, such as arundine, vibrindole A, turbomycin B, and certain anti-inflammatory agents. A total synthesis of an anti-breast-cancer agent is also demonstrated. Control experiments, Hammett analysis, HRMS and GC-MS studies reveal the reaction intermediates and reaction mechanism.  相似文献   
50.
Catalysis Surveys from Asia - Catalytic production of ethyl levulinate by alcoholysis of furfuryl alcohol with ethanol was investigated over H-mordenite supported Sn catalyst under atmospheric N2...  相似文献   
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