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2/3-取代硫基-5-邻羟基苯基唑类化合物的合成及抑菌活性 总被引:1,自引:0,他引:1
根据生物活性叠加原理,将"邻羟基苯基"和"唑类杂环"分子片断合理组合,设计合成了三个系列12种新型2/3-取代硫基-5-邻羟基苯基唑类化合物5a~7d.水杨酸甲酯在乙醇中与水合肼反应生成水杨酰肼,水杨酰肼与二硫化碳或硫氰酸铵和盐酸反应,生成5-邻羟基苯基-1,3,4-噁二唑-2-硫酮(2),5-邻羟基苯基-1,3,4-噻二唑-2-硫酮(3)和5-邻羟基苯基-4H-1,2,4-三唑-3-硫酮(4),最后在碱性条件下与(取代)卤代苯乙酮发生烷基化反应生成目标化合物.目标化合物的结构经1HNMR,IR和元素分析等表征确认.抑菌测试表明,质量浓度为0.01%时,对白色念珠菌、大肠杆菌的抑菌率高达92%以上,具有强抑菌活性;对金黄色葡萄球菌抑菌率高达82%以上,具有较强的抑菌活性;这表明目标化合物对不同菌株具有广谱抑菌活性,是一类极具潜力的抗真菌、抗革兰氏阴性菌化合物.构效分析表明,苯乙酮环上取代基的类型对化合物抑菌活性有重要影响,引入Cl,Br等卤原子,能显著增强化合物的抑菌活性,而引入CH3供电基团,能降低其抑菌活性. 相似文献
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2006—2007年度新建国家重点实验室终审工作于1月15日顺利完成。评审采取先现场考察、后集中会议答辩的方式,将进入终审的31个实验室按领域分为地学、工程、材料与化学等7个组分头进行评审。针对各参评实验室的研究方向和内容,共聘请了58位学术造诣深,对实验室建设与管理熟悉的专家作为评审专家。 相似文献
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以顺-1,2,3,6-四氢邻苯二甲酸酐为原料,经还原、环化、臭氧化、Wittig羰基烯化、酯化、二醇化和硫化等8步反应,合成了新型抗癌抗菌素"烯-二炔"的双环前体:6-硫杂-13-氧杂双环[9.3.0]-3,8-十四二炔.该合成路线步骤少,收率高,反应条件温和.6个新化合物4-9的结构均经元素分析、核磁共振、红外光谱和质谱确证. 相似文献
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The National Natural Science Foundation of China (NSFC) is a vital government agency supporting basic research and people to create knowledge and meet major national needs, where a rigorous and objective merit-based peer review mechanism is the key to funding the most promising research proposals. This invited comment overviews some recent attempts aimed at bettering the academic evaluation environment at the Department of Chemical Science in 2019, through measures such as grouped panel committee meetings, standardized panel committee meeting procedures, and review process refinement to improve the project review at panel committee meeting levels. 相似文献
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The Shell Conference on ... series began in 1985 and meetings are held approximately twice a year. The idea behind the conferences is to bring together invited scientists from both universities and industry, and representatives from different Shell Research laboratories, to create a forum to discuss the future directions of the chosen research area. These meetings have embraced a wide range of topics of interest to Shell Research as a whole.This particular conference, organised by the Analytical Department of the Koninklijke/ShellLaboratorium, Amsterdam (KSLA), was held on 4–6 October, 1987 at Hoenderloo in the Netherlands. The aim was to review the state-of-the-art and to discuss the future of molecular modelling and design. The programme itself consisted of a series of presentations on prescribed topics, panel discussions, and software and hardware demonstrations. Many of the presentations given consisted of overviews, experiences, advice and predictions for the future. The panel sessions, which involved the speakers within that session and a discussion leader who summarised some of the points made in an introduction, encouraged even further discussion and speculation. This overview attempts to catch the flavour of the meeting and convey some personal views that were expressed and conclusions drawn. 相似文献
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介绍近年国家自然科学基金化学科学部高分子科学学科的申请与资助情况、包括2007年详细数据与总体分析、近年学科项目增长数据.从某方面补充了我国内地高分子科学在国际上影响力变化的情况,给出了2008年高分子科学基金申请指南和申请书撰写注意事项,还概述了2007年学科发展战略研讨会. 相似文献
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Historical aspects of science are usually confined to special conferences, and receive only a brief mention in the introduction to talks at meetings addressing current topics. However, at the previous Seminar, several theoretical and experimental contributions were made, which discussed the historical development of surface science. Because of the considerable interest aroused by these presentations, we decided to keep the historical spirit alive, by telling the story of photoemission.
While field emission is the oldest area of surface science, photoemission is certainly one of the most important branches. Here, emphasis is placed on the early investigations, which are often scarcely mentioned, and on more recent work that has had significant impact on the progress of surface science. 相似文献
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Dave Armbruster 《Accreditation and quality assurance》2009,14(7):393-398
A goal of clinical laboratory science is to produce accurate and comparable patient test results for a specimen independent
of analytical methodology. The In Vitro Diagnostics Directive in Europe has provided the impetus for the U.S. in vitro diagnostic
(IVD) industry to adapt the concepts of Metrology, the science of measurement, including measurement traceability and measurement
uncertainty. The joint committee for traceability in laboratory medicine has provided a valuable database of internationally
recognized reference materials and methods and reference laboratories. Much of the responsibility for measurement traceability
falls on IVD manufacturers, but all global stakeholders, including the clinical laboratory profession, government Regulatory
bodies, metrology institutes, and the providers of EQA/PT surveys, must cooperate to progress toward this goal. The adaptation
of the concepts of Metrology to the clinical laboratory is an appropriate and logical development and it will continue in
the twenty-first century. 相似文献
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The scarcity of experiments with fertilisers, the poor domestic industry, and high prices for imported products made Russia lag far behind the leading agrarian countries in the research and use of fertilisers. The first experiments on fertilisers were connected mostly with the private estates of Russian nobility. Things began to change slowly by the turn of the twentieth century, when the Ministry of Agriculture launched a policy of agricultural science promotion, including the development of agricultural chemistry. It was the outbreak of World War I that created a powerful stimulus for fertiliser research in Russia. A specific Russian "symbiosis" emerged between military industry and agricultural chemistry. The numerous factories of explosives set up ad hoc produced vast amounts of waste products; modified, they could serve as fertilisers. In 1915, the Public Committee for Support of Fertilisers was organised. Eventually, this committee gave birth to the Institute of Fertilisers, the first institute founded by the Bolshevik government. Thus, the project of "chemicalisation of agriculture," usually described as a revolutionary endeavour, was firmly rooted in World War I. 相似文献
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J. van Brakel 《Foundations of Chemistry》1999,1(2):111-174
In this paper I present a historiography of the recent emergence of philosophy of chemistry. Special attention is given to the interest in this domain in Eastern Europe before the collapse of the USSR. It is shown that the initial neglect of the philosophy of chemistry is due to the unanimous view in philosophy and philosophy of science that only physics is a proper science (to put in Kant's words). More recently, due to the common though incorrect assumption that chemistry can in principle be reduced to physics, the neglect continued, even when interest in sciences such as biology and psychology entered more strongly in philosophy of science. It is concluded that chemistry is an autonomous science and is perhaps a more typical science than physics. 相似文献
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R. C. Moore M. Gasser N. Awwad K. C. Holt F. M. Salas A. Hasan M. A. Hasan H. Zhao C. A. Sanchez 《Journal of Radioanalytical and Nuclear Chemistry》2005,263(1):97-101
Summary The MARC-VI conference served as an excellent setting for a session organized to present and discuss the problems in nuclear science manpower and education. A panel discussion and contributed papers reflected the world-wide situation. This paper presents the major points of the panel discussion. As a result, a resolution on the current situation of nuclear chemistry and radiochemistry was drafted and endorsed by the conference attendees. 相似文献
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《Russian Chemical Bulletin》1994,43(2):325