乙酸乙酯

Two compounds were isolated from ethyl acetate extract of the fermentation of fungus 07-11,which obtained from the soil of Yunnan Province. They were identified as N-(4-hydroxy-2-methoxyphenyl)acetamide (1) and ergosta-7,22-diene-3,6-dione (2) respectively on the basis of spectral analyses and physical and chemical identifications.

从云南土壤真菌07-11号菌株的发酵液乙酸乙酯萃取物中分离得到2个化合物，通过理化鉴别和光谱测定，鉴定两化合物分别为N-(4-羟基-2-甲氧苯基)乙酰胺(1)和麦角甾7，22-二烯-3，6-二酮(2)。

And then we found that ytterbium trifluoromethethanesulfonate is a powerful catalyst for the reaction of amine and ethyl acetate.

然后研究了三氟甲磺酸镱催化的胺和乙酸乙酯的反应，从而合成了乙酰苯胺类化合物。

Results The average recovery of Dracaena's major components reached 80% after precipitated by acetonitrile first and then extracted by ethyl acetate.

结果通过乙腈沉淀蛋白，采用乙酸乙酯进行提取，可使含药血清中龙血竭特征成分的提取率达到80%以上。

Results The average recovery of Dracaena major components reached 80% after precipitated by acetonitrile first and then extracted by ethyl acetate.

结果 通过乙腈沉淀蛋白，采用乙酸乙酯进行提取，可使含药血清中龙血竭特征成分的提取率达到80%以上。

Thus, 3 mol of Ethyl acetoacetate were treated with 2 mol of formaldehyde to yield 80% of I.

用2摩尔的甲醛处理3摩尔的乙酰乙酸乙酯可得到80%的I。

L-Phenyl-3-methyl-5-pyrazoIone was synthesized by the reaction of ethyl acetoacetate and phenyl hydrazine in ethanol.

在无水乙醇的存在下，乙酰乙酸乙酯和苯肼为原料合成标题化合物。

Dehydroacetic acid was synthesized from acetacetic ether, and the influent factors of productive rate were investigated.

研究了以乙酰乙酸乙酯为原料合成脱氢醋酸过程中，催化剂的种类、用量以及反应时间对产物得率的影响。

Based on the problem of various types of catalyst and according to the features of carbonylation catalysts reactions, our team has been designed a series of new metal complexes of benimidazoles, which can be used for carbonylation catalyst of industry. Seven new benzimidazole derivatives were prepared by the o-phenylenediamine、oxalic acid、glycolic acid、monomethyl monopotassium malonate、ethyl cyanoacetate、succinic anhydride. The structures of them were confirmed by IR、Elemental analsis. The crystal structures of d and e were determined by X-ray single crystal diffraction of Germanic Bruker Smart APEX II CCD. The catalysis of them was tested by carbonylation reactions.

本文设计以邻苯二胺和草酸、羟基乙酸、丙二酸单甲酯、氰基乙酸乙酯、丁二酸单甲酯为原料采用PPA催化和无机酸催化法，合成了4种苯并咪唑-2-羧酸衍生物并进行了表征；培养了2个化合物d、e的晶体并测定和讨论了晶体结构；制备了3种未见报道的苯并咪唑金属配合物，对配合物在羰基化法制醋酐-醋酸反应的催化作用进行了初步试验。

Our main products include 5-Methyl-2-pyrazinecarboxylic acid series, Guanine series, Folic acid series, Methyl Cyanoacetate and Ethyl cyanoacetate series, we also have made great contribution in the development of cardiovascular drug, stomach drug, anti-inflammatory drug and antidepressants, such as Nizatidine, Acipimox, Glipizide, Zaltoprofen and Pregabalin, which have been put into production on large scare.

公司主要产品有5-甲基吡嗪-2-羧酸系列，鸟嘌呤系列，叶酸，氰乙酸甲酯，氰乙酸乙酯系列，在心血管药、胃药、消炎药、抗抑郁药等新品开发上有重大建树，先后研制成功，形成批量生产，如尼扎替丁、阿西莫斯、格列吡嗪、扎托洛芬、普瑞巴林，同时具备为客户定制化学品的能力。

DPPH method, pyrogallol method and Fenton reaction were used to study the scavenging ability of extracts with 95% ethanol, ethyl acetate, acetone, acetic acid, chloroform, methanol to free radical activity.

方法］应用DPPH法、邻苯三酚自氧化法和Fenton反应分别研究了浓度95%乙醇、乙酸乙酯、丙酮、乙酸、氯仿、甲醇提取物清除自由基活性的能力。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。