查询词典 substituted

From the photophysical behaviors of 1, 3, 4-triaryl-2pyrazoline compound (TPP16) at low temperature, it can be considered that the twisted configuration between pyrazoline ring and the non-substituted phenyl group on the position 1 is the fluorescence configuration of conjugated system Ⅰ, and the twisted configuration between pyrazoline ring and P-nitrobenzene group is fluorescence configuration of conjugated system Ⅱ.

研究了1，3，4-三芳基-2-吡唑啉化合物TPP16在低温时的发光情况，发现：在低温77K下，共轭体系Ⅰ(苯基-N1-N2＝C3-苯基)在非极性溶剂中不发荧光，在极性溶剂中有较强荧光发射；而共轭体系Ⅱ(N1-N2＝C3-C4＝对硝基苄叉)在非极性溶剂或极性溶剂中均有荧光发射，表明N1所联取代基与吡唑啉环相扭曲的构象是共轭体系Ⅰ的发光构象，而对硝基苄叉与吡唑啉环相扭曲的构象是共轭体系Ⅱ的发光构象。

Four chalcones were synthesized by aldol condensation reaction of acetophenone or para-substituted acetophenones with 2-phenyl-1,2,3-triazol-4-carboxaldehyde, which reacted with three hydrazines in glacial acetic acid under refluxing to give a series of pyrazoline derivatives.

以2-苯基－1，2，3-三唑基－4-甲醛为原料，与苯乙酮［或取代苯乙酮(1a~1d)］发生羟醛缩合，生成相应的查尔酮(2a~2d)，再与不同的肼反应，合成了12种新的5位含2-苯基－1，2，3-三唑基的吡唑啉衍生物3a~3d，4a~4d，5a~5d。

In order to search for the new pyrazolyl-heterocycles lead compounds, eight pyrazolyl- were synthesized from 3-ethyl-1-methyl- 4-substituted-5-pyrazolecarboxylic acid chloride and nitrogen heterocyclic rings such as 3-methyl-5-pyrazolone, 1H-3-ethyl-5-pyrazole ester, etc.

为了寻求新的含吡唑双杂环先导化合物，用 4 取代 1 甲基 3 乙基 5 吡唑甲酰氯与 3 甲基 5 吡唑酮、3 乙基 5 吡唑甲酸乙酯等含氮杂环反应得到了 8个新的含吡唑环的双杂环类化合物。

With NMR and DFT methods, the Michael additions of alkynyl Fischer carbene complex with a series of substituted pyrazoles as nucleophiles were also studied. All reactions follow the same three-step pathway mechanism described above. Substituents on 3-, 4- and 5- positions of the pyrazolyl ring affect the reaction in the steric and electronic manners, even to change the rate-determining step.

一系列取代吡唑与1-炔基Fischer卡宾化合物的Michael加成反应都遵循前面提出的三步机理，其中吡唑的3-， 4-， 5-位分别从电子效应和立体效应方面不同程度地影响着反应的进行，甚至改变反应的决速步骤。

In the third chapter, the synthesis of5-[(1"S)-1",2"-diacetyl-oxyethyl]-1-phenylpyrazol-3-carboxaldehyde oxime(2) from5-[(1"S)-1",2"-diacetyl-oxyethyl]-1-phenylpyrazol-3-carboxaldehyde(1) and phenyl-hydrazine were introduced firstly. The synthesis of nine dioxapyrrolino[3,4-c]pyrazoles containing chiral pyrazolyl moiety(6a-i) from 2 with N-substituted-phenylmaleimide by nonmetal oxidant IBD-initiated intermolecular 1,3-dipolarcycloaddition was described in detail.

第三章首先以5-[(1′S)-1′，2′-二乙酰氧基乙基]-1-苯基吡唑-3-醛(1)和苯肼为原料，合成了化合物5-(1′S)-1′，2′-二乙酰氧基乙基1-1-苯基吡唑-3-醛-苯腙(2)；再用化合物(2)与N-取代苯基马来酰亚胺反应，利用无金属氧化剂—IBD引发1，3-偶极反应，发生分子间的环加成，合成了9种新型手性吡唑连二氧代吡咯啉并

A series of pyridazino[3,2-c]1,2,4-triazoles were synthesized from hydrazides and 3-aryl-6- chloro pyridazine s (3a～3d), which were obtained from substituted benzene and succinic anhydride by Friedel-Crafts reaction, cyclization with hydrazine hydrate, dehydrogenation and chloro-substitution.

以取代苯和丁二酸酐为起始原料，经Friedel-Crafts反应，肼合环，Br2/HOAc氧化脱氢后得到一系列1，6-二氢-3-芳基-6-哒嗪酮(2a～2d)。然后将2a～2d与PCl5在POCl3中回流，得到相应的氯代产物3a～3d，将其与酰肼作用，合环后得到一系列未见报道的哒嗪并[3，2-c]1，2，4-三唑类化合物。所有化合物结构均经元素分析，IR，1HNMR和MS谱得以证实，并对其波谱性质进行了讨论

The enhancement of the reaction activity is attributed to the phasetransfer capability of the built-in quaternary ammonium and pyridinium salts of theMn catalyst. The effect of the internal quaternary ammonium and/or pyridiniumsalt on the epoxidation of substituted chromenes is similar to that of the externalpyridinium salts and ammonium halides.

分子内季铵盐和吡啶盐具有相转移能力，对于取代色烯不对称环氧化的作用与外加的吡啶盐和卤化铵的作用相似，使Mn催化剂催化取代色烯环氧化反应的活性明显提高。

A few of aryl pyridylalkyl ethers were synthesized by Mitsunobu reaction from substituted phenols 1a-b and pyridyl alcohols 2a-e at room temperature in 45%~70% yields.

在室温下，以取代苯酚1a-b和吡啶烷基醇2a-d为原料通过Mitsunobu反应合成了相应的芳基吡啶烷基醚，反应收率为45%￣70%，反应物2和1之比为1.11∶。

In this thesis, the acute lethal toxicity to Rana japonica tadpoles, the short-term phytotoxicity to Cucumis sativus and the population growth inhibition toxicity to Tetrahymena pyriformis of selected substituted phenols with multiple mechanisms of toxic action were compared and interspecies correlation was investigated.

本文比较了具有多种毒性作用机制的取代苯酚对两栖动物幼体的急性致死性毒性、对高等植物生长的抑制毒性以及对原生动物—四膜虫的种群生长抑制毒性，探讨了这一类污染物的毒性作用机制，进行了种间相关性研究。

As well as another example "Sour grapes'' is from "Aesop's Fables", and compared to the reachless things . There are "万事俱行,只欠东风"、"逼上梁山"、"叶公好龙 etc. in Chinese . All these examples show that the rich cultural heritage of their nation in the phrase which the others can not be substituted by language and culture , contains a rich culture that constituted the expression of the national languages of the distinct identities.

又如&Sour grapes''出自《伊索寓言》，比喻&可要可不及的东西&，汉语中有&万事俱行，只欠东风&、&逼上梁山&、&叶公好龙等，以上例子说明在民族各自丰富的文化遗产中产生的语词包含着丰富的民族文化意味，构成了各民族语言表达方式的鲜明独特性，是其他语言文化所不能替代的。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。