查询词典 acetyl

Penicillin G sulphoxide is esterified by N,N′-bistrimethylsilyl urea under the temperature 55℃ with a molar ratio 2.5∶1 between BSU and sulphoxide,and the ester obtained is ring-enlarged in the toluene under refluxing with the exist of catalyst-pyridine acetyl bromide.

摘 要 本文在制得青霉素G亚砜的基础上，完成了重排酸的扩环反应，重点探讨了扩环反应的最优化条件。青霉素G亚砜与N，N′-双脲在55℃下反应，得到亚砜的酯化物。

The acetyl chloride can lead a nearly complete substitution of phenyl groups with chlorine on silicon atoms.

在乙酰氯的作用下，n上的苯基能够被近乎完全的取代而生成氯代聚硅烷。

Compounds, N - methylene chloride acetyl groups - 2 - methyl - 2,5 - diethyl arene pbo.

化合物Ⅱ：N-二氯乙酰基-2-甲基-2，5-二乙基-1，3-恶唑烷。

acetyl chloride, a novel fluorescence derivatization reagent, has been developed for the determination of sterols and stanol .

采用荧光衍生化试剂2-(9-咔唑)乙酰氯，对天然产物谷甾醇、豆甾醇、菜油甾醇及谷甾烷醇的柱前衍生化条件，包括催化剂的种类、反应温度、衍生化时间等进行了考察，结果表明：催化剂选用三乙胺，反应温度80℃，时间20min，衍生产物具有恒定的最大检测响应值。

In view of the existence of the above shortcomings of traditional methods, using acetyl chloride instead of acetic acid as a raw material, do not use any catalyst, not heating, room temperature reaction synthesis of ethyl acetate.

鉴于传统方法存在以上缺点，采用乙酰氯代替乙酸作为原料，不使用任何催化剂，不加热，常温反应来合成乙酸乙酯。

The resultedα-methylamine was protected by acetyl chloride, and then was chlorosulfonated bychlorosulforic acid at -5℃-0℃followed by treatment with aqueous ammonia givingcompound A in 52.3% yield.

甲基胺再用乙酰基进行保护后，以HSO3Cl为试剂进行氯磺化反应，再用浓氨水进行反应，制得了乙酰基保护的苯磺酰胺类化合物。

Through the different concentrations of security agents on GSH conten, GST activity, ALS activity in different degree, basic verifies the methylene chloride acetyl groups were evil to reduce CFC sulfonylurea lung damage mechanism of corn.

通过不同浓度的安全剂对GSH含量，GST活性，ALS活性均有不同程度的促进作用，基本验证了二氯乙酰基恶唑烷类化合物减轻氯磺隆对玉米伤害的作用机理。我只有这些分数了，谢谢英语大侠了！

Stimulated astrocytes with Acetyl-β-Methylchline Chloride , Caffeine , Thapsigargin and carbonyl cyanide p- trifluomethoxphenylhydrazone by different types of combination, and observed their effects on 〓.

发现星型胶质细胞内的钙库包括：〓敏感和non—〓敏感的两种内质网钙库，可分别被MCh和CAF激活；线粒体钙库参与胞浆内Ca2+缓冲系统。

Part I, the Friedel-Crafts acylation on DAA and methyl dehydroabietic acid was carried out with acetyl chloride, benzoyl chloride or phthalic anhydride as acylating regents, anh- ydrous aluminum chloride as catalyst and with different solvents to compare with, we have got t- hree new compounds.

第一部分，分别以脱氢松香酸和脱氢松香酸甲酯为底物，乙酰氯、苯甲酰氯、邻苯二甲酸酐为酰化试剂，无水三氯化铝作催化剂，采用不同的溶剂及反应条件进行傅克酰基化反应，得到3个新化合物。

The phenyl acetate was synthesized from phenyl hydroxide and acetyl chloride by direct esterification and the factors influencing the synthesis were studied.Results showed that the optimal conditions were:n(C6H6O):n(C2H3OCl)=1:1.2,the amount of solvent cyclohexane was 40 mL(compared to 0.15 mol C6H6O),the reaction temperature was 20℃,and the reaction time was 5 h.

乙酸苯酯(分子式C8H8O2)是重要的药物中间体，它可以转化得到邻羟基苯乙酮和对羟基苯乙酮的混合物，可用于治疗急慢性黄疸型肝炎、胆囊炎等疾病，其中邻羟基苯乙酮是合成抗心律失常药盐酸普罗帕酮的重要中间体。

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。