一氯乙酸

Methods 4-Hydroxy- benzonitrile was treated with sodium hydrogen sulfide and anhydrous magnesium chloride in dimethyl formamide to give thioamide, which was then directly cyclized with ethyl 2-chloroacetoacetate without separation to give ethyl 2-(4-hydroxyphenyl)-4-methylthiazole-5-carboxylate(2) in one-pot; then 2 was formylated with Duff reaction adopting hexamethylenetetramine in trifluoroacetic acid to give ethyl 2-(3-formyl-4-hydroxyphenyl)-4-methylthiazole-5-carboxylate(3); finally, the target compound was obtained by the treatment of 3 with hydroxylamine hydrochloride and sodium formate in formic acid.

采用"一勺烩"方法，以4-羟基苯甲腈为起始原料，首先与硫氢化钠和无水氯化镁在N，N-二甲基甲酰胺中反应，所得中间体不经分离，直接加入2-氯乙酰乙酸乙酯进行环合反应，得到2-(4-羟基)苯基-4-甲基-5-噻唑甲酸乙酯（2）；然后通过六亚甲基四胺/三氟乙酸进行Duff反应，得到2-(3-甲酰基-4-羟基)苯基-4-甲基-5-噻唑甲酸乙酯（3）；再经盐酸羟胺/甲酸/甲酸钠体系脱水得到目标化合物。

The bivalent radical CO.Indocin is the trade name of this nonsteroidal anti-inflammatory drug.

氯苯基甲氧基甲基吲哚乙酸是一种非固醇抗炎药物的商标名称。

The divalent radical UO22+.Indocin is the trade name of this nonsteroidal anti-inflammatory drug.

氯苯基甲氧基甲基吲哚乙酸是一种非固醇抗炎药物的商标名称。

A salt of bromic acid.Indocin is the trade name of this nonsteroidal anti-inflammatory drug.

氯苯基甲氧基甲基吲哚乙酸是一种非固醇抗炎药物的商标名称。

Any of several esters, other than the ethyl ester, of carbamic acid .

氯苯基甲氧基甲基吲哚乙酸是一种非固醇抗炎药物的商标名称。

A salt or ester of carbamic acid, especially one used as an insecticide.

氯苯基甲氧基甲基吲哚乙酸是一种非固醇抗炎药物的商标名称。

Two synthetic routes of Caffeine have been determined and investigated after the analyzing and trying for the literal synthetic methods. In one route, the target compound was prepared from chloroacetyl chloride through six steps, the total yield is 50.5 %. In another route, the target compound was obtained from cyanoacetic acid through six steps, the total yield is 45%.

对目前咖啡因工业生产工艺进行了研究，并分析了咖啡因工业生产中所存在的问题，本文提出两条可行的工业化合成路线：一条是以氯乙酰氯为起始原料，经过六步反应制得目标化合物，总收率50.5％；另一条是以氰基乙酸为起始原料经过六步反应制得目标化合物，总收率45％。

The method of degradation of 2,4-dichlorophenoxyacetic acid by ozonation in a cylindrical bubbling tower reactor was proposed.

引言2，4-二氯苯氧乙酸(2，4-D，又名2，4-滴)是一种广泛使用的除草剂[1]，应用历史较长，是我国主要的除草剂品种之一，用量也比较大。

Methods 4-Hydroxy- benzonitrile was treated with sodium hydrogen sulfide and anhydrous magnesium chloride in dimethyl formamide to give thioamide, which was then directly cyclized with ethyl 2-chloroacetoacetate without separation to give ethyl 2-(4-hydroxyphenyl)-4-methylthiazole-5-carboxylate(2) in one-pot; then 2 was formylated with Duff reaction adopting hexamethylenetetramine in trifluoroacetic acid to give ethyl 2-(3-formyl-4-hydroxyphenyl)-4-methylthiazole-5-carboxylate(3); finally, the target compound was obtained by the treatment of 3 with hydroxylamine hydrochloride and sodium formate in formic acid.

采用&一勺烩&方法，以4-羟基苯甲腈为起始原料，首先与硫氢化钠和无水氯化镁在N，N-二甲基甲酰胺中反应，所得中间体不经分离，直接加入2-氯乙酰乙酸乙酯进行环合反应，得到2-(4-羟基)苯基-4-甲基-5-噻唑甲酸乙酯（2）；然后通过六亚甲基四胺/三氟乙酸进行Duff反应，得到2-(3-甲酰基-4-羟基)苯基-4-甲基-5-噻唑甲酸乙酯（3）；再经盐酸羟胺/甲酸/甲酸钠体系脱水得到目标化合物。

A method used to simutaniously analyze the residues of herbicides 2, 4-dichlorophenoxyacetic acid (2,4-D), 2-(2,4-dichiorophenoxy) propanoic acid (2,4-DP) and 2,4-dichiorophenoxybutyric acid (2,4-DB) in garlic was developed in our study.

本研究建立了一种应用基质固相分散－高效液相色谱法，同时测定大蒜中2，4-二氯苯氧乙酸、2，4-二氯苯氧丙酸及2，4-二氯苯氧丁酸等3种2，4-D类除草剂残留的方法。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。