乙酐

From the synthesis of morphine and acetic anhydride derivatives of heroin history, so far, heroin still known as the "King of Drugs."

从吗啡与乙酐合成其衍生物海洛因的历史，到目前为止，海洛因仍被号称"毒品之王"。

It was found that SnCl_2·2H_2O is an effective catalyst for the acylation of 2,3-dimethyl-2-butene by acetic anhydride at room temperature.

发现SnCl2·2H2O是室温下2，3-二甲基-2-丁烯与乙酐进行酰化反应的有效催化剂。

Then add, in the following order, 93±3 mg (0.5 mmol) of ferrocene, 0.35 mL of acetic anhydride, and 0.1 mL of 85% phosphoric acid.

然后按以下的次序，加入93±3 mg (0.5 mmol)的二茂铁，0.35ml的乙酐，和0.1ml 85%的磷酸。

In this paper, the effects of different catalyst combinations on the synthesis of α-chloro-dodecanoic acid were investigated, in which a series of acyl chlorides such as 4-toluene sulfonyl chloride, dodecanoyl chloride, chlorosulphonic acid , etc.

本文从烯酮式反应机理出发，以α-氯代十二酸的合成为模型，对酰氯化试剂(对甲苯磺酰氯、十二酰氯、氯磺酸等)和质子酸催化剂(如H型离子交换树脂、氯磺酸、对甲苯磺酸、醋酸等)进行组合和选择，并与文献报道的特殊添加剂乙酐比较，研究不同催化体系在酸催化合成α-氯代脂肪酸时的催化作用。

The taurohyodeoxycholic acid was synthesized by aminolysis of sodium taurine with carboxy-carbonate mixed anhydride prepared by reacting hyodeoxycholic acid with ethyl chloroformate at the present of triethylamine.

猪去氧胆酸与氯甲酸乙酯在三乙胺存在下反应生成羟酸－碳酸乙酯混合酐，而后将其与牛磺酸钠进行氨解反应，合成猪磺去氧胆酸。

Then the protected D-mannitol, mixed with lead tetraacetate, hippuric and acetic anhydride, were refluxed in THF for 18 h in a one-pot two step reaction to afford a chiral precursor-2-phenyl-4-[-2,3-O-]-propylidene-5(4H)-oxazolones.

产物与四乙酸铅、马尿酸、乙酐于THF中回流18 h完成一釜二步反应，纯化后得到含有手性碳原子的环丙烷氨基酸前体-2 苯基-4-[-2，3-O-]丙叉？

The Company perennial operating a variety of organic chemical raw materials, varieties include: methanol, ethanol, ethylene glycol, n-butyl alcohol, isobutyl alcohol, isopropyl alcohol, acetic acid, vinyl acetate, acetic acid acetate, acetic acid small lipid , styrene, toluene, phthalic anhydride, xylene, acetone, butanone, cyclohexanone, DMF, sulfuric acid, methyl isobutyl ketone, glycol ether, three toluene, octyl resin, melamine, etc. and so on.

本公司常年经营各种有机化工原料，品种有：甲醇、乙醇、乙二醇、正丁醇、异丁醇、异丙醇、冰醋酸、醋酸乙烯、醋酸乙脂、醋酸丁脂、苯乙烯、甲苯、苯酐、二甲苯、丙酮、丁酮、环己酮、DMF、硫酸、甲基异丁基酮、乙二醇丁醚、三甲苯、二辛脂、三聚氰胺，等等。

I for Hong Kong and Taiwan-owned business enterprises in the chemical industry more than twenty years of marketing, agent distribution Chemical famous brand, the main service items are as follows: methanol, ethanol, ethylene glycol, n-butyl alcohol, isobutyl alcohol, isopropyl alcohol, ice acetic acid, vinyl acetate, acetic acid acetate, acetic acid Ding resin, styrene, toluene, phthalic anhydride, xylene, acetone, butanone, cyclohexanone, DMF, sulfuric acid, methyl isobutyl ketone, glycol ether, three toluene, octyl resin, melamine, and so on.

我公司为港台商独资企业，于化工行业行销二十余年，代理经销国外著名化工品牌，主要服务项目如下：甲醇、乙醇、乙二醇、正丁醇、异丁醇、异丙醇、冰醋酸、醋酸乙烯、醋酸乙脂、醋酸丁脂、苯乙烯、甲苯、苯酐、二甲苯、丙酮、丁酮、环己酮、DMF、硫酸、甲基异丁基酮、乙二醇丁醚、三甲苯、二辛脂、三聚氰胺，等等。

This year the company operating the various organic chemical raw materials, varieties are: methanol, ethanol, ethylene glycol, butanol, isobutanol, isopropanol, glacial acetic acid, vinyl acetate, B lipid, Ding acetic acid lipid, styrene, toluene, phthalic anhydride, xylene, acetone, butanone, cyclohexanone, DMF, sulphuric acid, methyl isobutyl ketone, glycol Dingmi, three toluene, 2 Xin fat, melamine.

本公司常年经营各种有机化工原料，品种有：甲醇、乙醇、乙二醇、正丁醇、异丁醇、异丙醇、冰醋酸、醋酸乙烯、醋酸乙脂、醋酸丁脂、苯乙烯、甲苯、苯酐、二甲苯、丙酮、丁酮、环己酮、DMF、硫酸、甲基异丁基酮、乙二醇丁醚、三甲苯、二辛脂、三聚氰胺。

The company operating a variety of perennial organic chemical raw materials, varieties include: methanol, ethanol, ethylene glycol, n-butyl alcohol, isobutyl alcohol, isopropyl alcohol, acetic acid, vinyl acetate, acetic acid acetate, acetic acid Ding resin, styrene, toluene , phthalic anhydride, xylene, acetone, butanone, cyclohexanone, DMF, sulfuric acid, methyl isobutyl ketone, glycol ether, mesitylene, octyl resin, melamine.

本公司常年经营各种有机化工原料，品种有：甲醇、乙醇、乙二醇、正丁醇、异丁醇、异丙醇、冰醋酸、醋酸乙烯、醋酸乙脂、醋酸丁脂、苯乙烯、甲苯、苯酐、二甲苯、丙酮、丁酮、环己酮、DMF、硫酸、甲基异丁基酮、乙二醇丁醚、三甲苯、二辛脂、三聚氰胺。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。