分子内的
- 与 分子内的 相关的网络例句 [注:此内容来源于网络,仅供参考]
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In our research on study chemical reaction of active methylene compounds and brom-acetophenone. Because of brom-acetophenone is compound that contain carbonyl and halogen ,which will take place electrophilic substitution and nucleophilic addition. When active methylene compounds are ethyl acetoacetate and β-diketone, controlling reaction condition, we have found that mono-substitution's production and di-substitution's. production is isolated; active methylene compounds are acetoacetanilide and acetoacetanilide derivate, pyrrolidin-2-one derivants were obtained by substitution and close-ring reaction .but there is no report about it.
本文是让活泼亚甲基类化合物与溴代苯乙酮发生化学反应,由于溴代苯乙酮是含有羰基的卤代烃结构,它可以发生亲电取代和亲核加成反应,当活泼亚甲基类化合物为乙酰乙酸乙酯和β-二酮时,控制反应条件可以发生单取代和双取代两种产物;当活泼亚甲基类化合物为乙酰乙酰芳胺类化合物来反应时,溴代苯乙酮中的羰基与氨基会发生分子内的关环反应生成吡咯烷-2-酮衍生物,这在以前的研究中是没有发现的。
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Firstly,starting from 2,2-dimethyl-1,3-propan-diol,synthesis of-pedamide was finished in 17 steps.The pyran ring was formed in a S_N2 substitution of hydroxyl and epoxide.
以新戊二醇为起始原料,通过基于分子内的羟基与环氧的S_N2亲核取代构筑吡喃环的方法,经过17步反应完成了外消旋的Pedamide的合成。
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Started from D-tyrosine, we obtained the tetramic acid 96 using Jouin reaction. The assembly of the second fragment 109 was stared from 1,4-butandiol,using asymmetric alkylation reaction developed by Oppolzer as a key step. Coupling of the tetramic acid 96 with 109 provided the key intermediate 110 according to Yoshii\'s procedure. After remove protective group and Sharpless epoxidation, we obtained the key intermediate 113. Its macrocyclization to form the final product is in progress.
本论文的第二章主要对Macrocidin A开展了合成工作,我们从D构型的酪氨酸出发,经过官能团转换;利用Jouin反应生成Tetramic acid 96,另外一个片断从1,4-丁二醇开始经过多步反应生成碘化物104,利用Oppolzer发展的手性樟脑磺酰胺为辅基参与的不对称烷基化反应,引入手性甲基,生成关键中间体109,接着通过Yoshii发展的方法连接96和109生成110,经过Sharpless不对称环氧化反应建立环氧化合物,然后脱去保护基得到关环前体113,分子内的Mitsunobu反应进行关大环反应正在进行之中。
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The electron donorability of the electron donor part of the fulgide decreases when cationcomplexes with crown ether, and the intromolecular charge transfereffect reduces.
金属离子较大的电荷密度以及金属离子与冠醚较好的匹配使冠醚俘精酸酐分子内的电荷转移更不易进行,造成了光谱较大的蓝移。
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Results show that intramolecular hydrogen transfer is not favored in view of the energy trend along IHT coordinate in the region such as hypericin's peri region, where two hydrogens of hydroxyl groups bond with a common oxygen of carbonyl group and exists two IHBs in the peri region. However, intramolecular proton transfer often occur in the molecule with hexahydric cycle hydrogen bond, where only one pair of adjacent hydroxyl group and carbonyl group.
此外选择设计了一个具有三个分子内氢键的体系,兼具金丝桃蒽酮和其他苝醌类光敏剂的分子内氢键特点,研究表明两个羟基氢与共同的羰基氧形成的氢键由于存在较高的势垒,很难发生分子内氢传递,即具有金丝桃蒽酮端位结构的分子其分子内氢传递很难发生,而一般的能形成六元环状结构的分子内氢键体系容易发生分子内氢传递。
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The mechanisms of intramolecular biaryl nonphenolic coupling were explored by reactions of different 1,4-biaryl substituted butanes with DDQ in TFA.
通过对含不同取代基的芳环化合物、1,4-二芳基丁烷链上含不同取代基化合物与DDQ在TFA中进行非酚氧化偶合和重排反应的研究,对分子内的二芳基非酚氧化偶合反应机理作了深刻的探讨。
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The two-photon absorption cross-sections of these styryl derivatives were determined by Z-scan technique, and the benzothiazolium derivatives exhibited the largest TPA cross-sections (10〓s·cm〓/photon) and the best power limiting ability at high operable incident intensity. The results show that the benzothiazolium derivatives are promising organic compounds as two-photon absorption optical limiting materials. 2. Several organic dyes active to 800nm femtosecond laser with D-π-A structure were designed and synthesized.
研究了它们的上转换荧光、上转换激射和光限幅行为,通过改变染料分子共轭体系的大小,首次实现了在576nm-635nm范围内的双光子上转换激光波长的调节,其中噻唑啉碘盐类二苯乙烯化合物的双光子上转换激射峰(576nm)是迄今在1064nm皮秒激光作用下能够得到的最短波长的激光;阴离子显著改变上转换激射效率,但对上转换荧光峰和激射峰的位置影响很小;增加溶液的浓度,上转换荧光光谱和激射光谱红移,并在一定的浓度范围内,能够有效的提高上转换激射效率;利用Z-扫描技术测定了染料分子的双光子吸收截面,发现苯并噻唑类染料分子的双光子吸收截面高达10〓s·cm〓/photon,而且在较大的入射光强范围内,这类染料分子具有较大的光限幅能力,是一类作为双光子吸收光限幅材料很有潜力的染料分子。
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Comparably, we have synthesized three conjugated dendrimers bearing triphenylamine moiety as dendrons and benzene as core, which possess ACQ properties.
考察了以蒽为核的dendrimers在低温和室温下的荧光光谱,发现在低温时,它们的荧光强度显著增强,这是由于在低温时,分子内的振转运动受到限制,导致了荧光增强。
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In the course of our study the chemistry of arenes contaning allylic acetates moiety under the catalysis of palladium, we found an efficient synthesis of benzocycles via intramolecular Friedel-Crafts reaction of halogen free 6-acetoxy-4alkenyl arens.
我们在设计钯催化的碳—氢键活化时,发现了含有烯丙基醋酸酯侧链的芳烃的三氟醋酸促进的分子内的Friedel-Crafts反应,从而为有效合成苯并六元环结构提供了一个方便的方法。
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Furthermore, the structures of DNA molecules varying with concentration of new modification agent were studied, and it was found that when the new modification agent concentration was 1:1000, DNA molecules were successfully fixed and extended on the modified mica surface and well-distinguished DNA strands were imaged by AFM.
并进一步观察了不同DAPS浓度下DNA分子的吸附行为,发现当DAPS/甲醇体积比浓度为1:100时,DNA分子呈现出大而复杂的形态,发生了分子内和分子间的碱基相互配对;当体积比浓度为1:3000时,即没有分子内和分子间的碱基相互配对,也
- 推荐网络例句
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The split between the two groups can hardly be papered over.
这两个团体间的分歧难以掩饰。
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This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.
这种做法不仅鼓励了更多的反应,而且减少跟风的可能性。
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The new PS20 solar power tower collected sunlight through mirrors known as "heliostats" to produce steam that is converted into electricity by a turbine in Sanlucar la Mayor, Spain, Wednesday.
聚光:照片上是建在西班牙桑路卡拉马尤城的一座新型PS20塔式太阳能电站。被称为&日光反射装置&的镜子将太阳光反射到主塔,然后用聚集的热量产生蒸汽进而通过涡轮机转化为电力