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1.
报道四苯并卟啉锌/芳晴/有机玻璃TZT/AC/PMMA体系光化学烧孔的光谱稳定性、多重烧孔及激光诱导的填孔效应。 关键词:  相似文献   
2.
A highly stereoselective synthesis of the side Chain enantiomers of brassinolide and dolicholide through an aldol reaction of 2-(4-methoxy benzyloxyl) proplonylaldehyde (5) with the anion of 1- ( tert -butyldimethylsiloxy )-3-methyl-2-butanone ( 6 ) is described.  相似文献   
3.
西松烷型二萜类化合物是一大类广泛分布于松脂、烟草、陆地动物及海洋生物体中的具有十四元碳环骨架的化合物.其结构新颖复杂,且大多具有显著和广谱的生物活性.近几十年来,有关这类化合物的研究已引起了人们的极大兴趣.因此,开展这类天然产物及其类似物的全合成及构效关系的研究不仅具有重要的学术价值,而且具有潜在的应用前景.  相似文献   
4.
Optically pure S-5-hexadecanolide (1) has been easily prepared from readily available aldehyde 2 and cyclopentanone (3) using L-proline-catalyzed asymmetric aldol reactions as the key step.  相似文献   
5.
Brassinolide(compound 1) and cathasterone(compound 2)(Scheme 1),whichis the biosyn-thetic precursor of compound 1,are a new type of promoting materials for plant growh[1.2].  相似文献   
6.
树脂对防风粗多糖脱色效果   总被引:6,自引:0,他引:6  
树脂对防风粗多糖脱色效果;防风;多糖;树脂;脱色  相似文献   
7.
利用活性结构拼接原理,将高效杀螨剂吡螨胺分子的吡唑环部分引入酰基(硫)脲化合物中,以1-甲基-3-乙基-4-氯-5-甲酸基吡唑和2-氨基-4,6-二取代嘧啶为起始原料,通过多步反应合成了5种N-(4,6-二取代嘧啶-2-基)-N′-(1-甲基-3-乙基-4-氯吡唑-5-基)甲酰基脲和5个N-(4,6-二取代嘧啶-2-基)-N′-(1-甲基-3-乙基-4-氯吡唑-5-基)甲酰基硫脲化合物,其化合物结构经IR、1HNMR及元素分析测试技术确证。初步生物活性试验表明,在50mg/L质量浓度下目标化合物的杀螨活性不太理想,但有些化合物具有较好的除草活性,其中化合物Ⅰb、Ⅰc和Ⅰe对稗草主根的生长抑制率大于60%。  相似文献   
8.
1 1 INTRODUCTION Sulfonamides exhibit higher pharmaceutical and pesticidal characteristics such as fungicidal, antitu- mor and herbicidal activities[1~6]. On the other hand, many ferrocene derivatives have excellent biological or physiological activities, which are used in biology and medicine owing to their lipophilicity, aroma- ticity, biological oxidisability and lower toxicity[7, 8]. In search for effective fungicide, we introduce ferro- cenyl into sulfonamide molecule to synthesize a …  相似文献   
9.
A simple and efficient procedure has been developed for the synthesis of organostannane compounds by one-pot reaction of stannane halides, magnesium turnings and organic halides in the presence of 1,2-dibromoethane under ultrasound irradiation.  相似文献   
10.
A metabolomic investigation of chronic unpredictable mild stress (CUMS) rats was carried out. Plasma obtained from Sprague-Dawley (SD) rats treated by CUMS was analyzed using gas chromatography/mass spectrometry. Thirty-seven metabolites were identified among the detected compounds. Subsequent data analysis using the t test and principal component analysis (PCA) revealed significant metabolic changes in the rats' plasma after CUMS treatment. Clear separation between the model and control group was achieved, and the level of twelve metabolites, including amino acids, sugar, organic acids and fatty acids, were significantly different between plasma samples from the controls and CUMS group. These observations suggested that the depressed state may be associated with perturbation of amino acid metabolism, energy metabolism and glycometabolism. The study suggested that the metabolomics approach could be used as a potential powerful tool to investigate the biochemical change in certain physiopathological conditions, such as depression, as an early diagnostic means.  相似文献   
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