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521.
In this paper,aliphatic amidediol was synthesized and mixed with glycerol used as a plasticizer for preparing thermoplastic starch(AGPTPS).The yield of aliphatic amidediol was 91%.FF-IR expressed that the mixture of aliphatic amidediol and glycerol formed stronger and stable hydrogen bond with starch molecules compared to the native cornstarch.By scanning electron microscope(SEM)native cornstarch granules were proved to transfer to a homogeneous continuous system.After being stored for a period time at room temperature,the mechanical properties of AGPTPS were also studied.As a mixed plasticizer,aliphatic amidediol and glycerol would be practical to extend TPS application scopes.  相似文献   
522.
Synthesis and cytotoxic activity of novel curcumin analogues   总被引:3,自引:0,他引:3  
Five novel curcumin analogues bearing different substituents at 4-position of phenyl group were synthesized. Their structures were confirmed by NMR and HRMS spectrum. Their cytotoxic activities against six tumor cell lines were tested by the standard MTT assay in vitro. The results indicated that four analogues (1A-1C, 1E) with solubilizing moieties showed selective potent cytotoxicity against HepG2, HeLa and CT26 cell lines, and analogue 1A and 1C exhibited more potent cytotoxicity than curcumin against CT26 cell line. It was suggested that introduction of appropriate substituents to 4-position of phenyl group might be a potential option for structural modification of curcumin.  相似文献   
523.
Novel chiral tetralin compounds were designed and synthesized, and their antifungal activities in vitro were tested. The results showed that all of target compounds had potent antifungal activities, and were stronger than that of control compounds tetrahydroisoquinolines. The binding model of lead molecules in the active site of CYP51 of Candida albicans showed that lead compound specifically interacted with the amino acids residues in the active site, without binding with the heme of CYP51, which was different from azole antifungal drugs. The present study might afford a novel lead molecule to develop non-azole CYP51 inhihitars of fungi.  相似文献   
524.
By the addition of rice wine koji,enhancement of the reactivity was observed for the baker's yeast reduction ofβ-keto esters into (S)-β-hydroxy esters with high enantiomeric purity (73-98%).  相似文献   
525.
Two species of N-arylpyrazoles containing active amino group were synthesized.And formylations of N-arylpyazoles containing amino in different position of pyrazole rings using Vilsmeier-Haack reaction gave a series of useful pyrazole intermediates.The important features of this protocol were cheap materials,easy process,mild reaction conditions and good yield of products.  相似文献   
526.
Synthesis of Cubic Mesoporous Silica MCM-48by Mixed Micellar Templates   总被引:2,自引:0,他引:2  
In 1992, Mobil researchers introduced a novel concept in the synthesis of mesoporous silicas (M41S)1,2 by using a self-assembled molecular array of surfactant molecules as structure-directing template. Depending on the shape of their templates and the respective resulting pore structure, the M41S family was identified : MCM-41(hexagonal), MCM-48(cubic), and other species. MCM-41 with honeycomb arrays of nonintersecting channels was shown to be the easiest to synthesize1. MCM-48 containin…  相似文献   
527.
The research of electrocatalytic oxidation of small organic molecules such as methanol, formaldehyde and formic acid has been fascinating electrochemists for more than thirty years, owing to its significance in energy conversion and reaction mechanisms. The surface adsorbed species involved in these electrocatalytic reactions, especially reactive and poisoning intermediates, have been investigated by electrochemical, spectroscopic and other physicochemical methods1. However, Raman spectrosco…  相似文献   
528.
使用密度泛函理论B3LYP方法和二阶微扰理论MP2方法对由1-甲基尿嘧啶与N-甲基乙酰胺所形成的氢键复合物中的氢键强度进行了理论研究, 探讨了不同取代基取代氢键受体分子1-甲基尿嘧啶中的氢原子对氢键强度的影响和氢键的协同性. 研究表明: 供电子取代基使N-H…O=C氢键键长r(H…O)缩短, 氢键强度增强; 吸电子取代基使N-H…O=C氢键键长r(H…O)伸长, 氢键强度减弱. 自然键轨道(NBO)分析表明: 供电子基团使参与形成氢键的氢原子的正电荷增加, 使氧原子的负电荷增加, 使质子供体和受体分子间的电荷转移量增多; 吸电子基团则相反. 供电子基团使N-H…O=C氢键中氧原子的孤对电子轨道n(O)对N-H的反键轨道σ*(N-H)的二阶相互作用稳定化能增强, 吸电子基团使这种二阶相互作用稳定化能减弱. 取代基对与其相近的N-H…O=C氢键影响更大.  相似文献   
529.
特殊的单原子层二维sp2碳结构给石墨烯带来众多独特的性能和潜在的应用. 然而, 单层石墨烯容易聚集并会逐渐重新石墨化, 这成为其应用的一个重要障碍. 本文报道了一种新策略来解决这个问题, 即通过在石墨烯表面引入sp2碳纳米结构作为永久的波纹来阻止石墨烯的聚集和石墨化, 并使之在溶液中易于分散和稳定. 和其他功能化方法不同, 该方法没有引入杂原子, 不破坏石墨烯的结构和功能. 制得的石墨烯具有优异的导电性能(~65000 S·m-1), 并具有较好的溶液稳定性.  相似文献   
530.
我们发展了一种用于预测有机小分子化合物水溶解度(logS)的经验方法XLOGS. 它本质上是一种加合模型, 采用83种原子/基团类型和3个校正因子作为模型的描述符.该方法还可以根据一个合适的参照分子的logS实验值来计算未知化合物的logS值. 我们将XLOGS模型在由4171个化合物组成的训练集上进行了参数化, 多元线性回归获得的相关系数R2和标准偏差SD分别为0.82和0.96单位. 将该训练集进一步分为仅含液体化合物和仅含固体化合物的两个子集. XLOGS模型在这两个子集上的回归结果显示前者优于后者(标准偏差分别为0.65单位和0.94单位). 还利用log1/S和logP(脂水分配系数)之间的差值来研究XLOGS方法在液体和固体化合物数据集上的表现. 研究结果表明: XLOGS等加合法模型更适合应用于这两者差值接近于0的化合物. 我们还将XLOGS和其他三种流行的logS计算模型(包括Qikprop, MOE-logS和ALOGPS)在一个含有132个类药化合物的独立测试集上进行了比较. 总体而言, 我们的研究结果为加合法模型在水溶解度预测方面的合理应用提供了指导.  相似文献   
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