乙酰乙酸

Bromo-2′,4′-dichloroacetophenone was synthesized in three steps,w hich were bromization ,chlorination and acylation,from glacial acetic acid and m -dichlorobenzene.

以冰乙酸和间二氯苯为原料，经溴化、氯化、酰化三个步骤，制得 2—溴- 2′，4′-二氯苯乙酮，产率达 70 %。

ResultThe Buxus Microphylla leaf ethyl acetate extraction (high-dose and low dose) have obvious effect on reducing the serum total cholesterol and triglyceride, moreover, the high-dose ethyl acetate extract reducing blood lipid was better than the other extracts.

结果 小叶黄杨叶乙酸乙酯提取物的高、低两个剂量组均有显著的降低血清总胆固醇和三酰甘油的作用，小叶黄杨叶的水提取物和石油醚提取物均有显著的降低血清中总胆固醇的作用，小叶黄杨叶氯仿提取物及正丁醇提取物均无降血脂的作用。

The synthesis of the intermediate amidetriazinone was a crucial step in the synthesis of triazinone. Ethyl acetate was used as the initial material then was carried out for five steps hydrazine hydrate, triphosgene, chloroacetone, hydrazine hydrate respectively with the yield of 59.8%.

三嗪酮类化合物的合成关键是中间体氨基三嗪酮，本文以乙酸乙酯为起始原料，经过酯的肼解、成环反应、胺的烷基化、酮和肼的缩合、酰胺的水解五步反应合成中间体氨基三嗪酮，其收率达59.8%。

Ingredients: water,decyl glucoside,glycerin,sodium cocoamphodiacetate,sodium pca,polysorbate-20,cocamidopropyl betaine,carya illinoensis powder,panthenol,carbomer,aloe barbadensis leaf juice,lavandula angustifolia oil,perfume,tetrasodium edta,lactic acid.

主要成份：去离子水，葵基葡聚糖，甘油，椰油两性二醋酸二钠，吡咯烷酮羧酸钠，聚山梨醇酯-20 ，椰油酰胺丙基甜菜碱，核桃粉，泛醇，卡波姆，芦荟叶萃取物，薰衣草精油，香精，乙二胺四乙酸四钠，乳酸。

The free fatty acids were extracted with petroleum ether and were separated on silicon gel column chromatography. The ethyl acetate-soluble lipid fraction and water-soluble lipid fraction were subjected to hydrochloric acid-catalyzed methanolysis, then were extracted with petroleum ether, respectively.

用石油醚提取低极性组分，经硅胶柱层析分离得到游离脂肪酸；用乙酸乙酯提取酯溶性神经酰胺及其衍生脂类，提取物和残余的水溶性脂类分别经盐酸甲醇解，水解产物再用石油醚提取。

Then we completed the first total synthesis of-Plakoridine A using Eschenmoser couping reaction as akey step. During the synthesis we found the choice of protecting groups and the configuration of the chiralcenter of the substrate play an important role to the key Eschenmoser reaction,so we think our successwould be of guide for synthesizing other polysubstituted pyrrolidines or piperidines.

在论文的第一章中，我们先以易得的对羟基苯乙酸乙酯为原料经多步反应制得了所需的β氨基酸酯，然后利用立体选择性的Aldol缩合反应和内酰胺化反应制得了Plakoridine Alactam，随后，以Eshenmoser缩合反应为关键步骤完成了生物碱-Plakoridine A的首次不对称全合成。

To synthesize aryl pyrimidines by taking benzene, methyl benzene ,acetic ether,1,2-dichloroethane as solvent,the yield and purity of the product are high by taking methyl benzene as solvent.

分别选用苯、甲苯、乙酸乙酯、二氯乙烷作为溶剂合成桂皮酰哌啶，结果表明甲苯作为溶剂时产品纯度高，收率高，可用于大规模生产。

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。