英语人>网络例句>乙二酸 相关的搜索结果
网络例句

乙二酸

与 乙二酸 相关的网络例句 [注:此内容来源于网络,仅供参考]

Ethyl 4-[(1-hydroxy-1-methyl)ethyl]-2-propyl-1H-imidazole-5-carboxylate,the key intermediate of Olmesartan ,was synthesized from butanoic acid and o-phenylenediamine via condensation under microwave-irradiation,oxidation,esterification and the Gringard reaction.

用正丁酸与邻苯二胺为原料,在微波照射下缩合成2-丙基苯并咪唑,再氧化开环制得2-丙基咪唑二羧酸,再经酯化、Gringard反应制得抗高血压药物奥美沙坦的关键中间体2-丙基-4-[(1-羟基-1-甲基)乙基]-1H-咪唑-5-羧酸乙酯,总收率32.2%。

The influences of different surfactants (sodium dodecyl sulfate, sodium cholate and sodium deoxycholate), different electrolytes (sodium phosphate monobasic, sodium tetraborate and 3-cyclohexylamino-1-propane sulfonic acid), buffer pH and organic modifiers on the determination of sialic acid were studied.

其次建立了一种测定唾液酸的在线富集CZE法,该方法用40 mM磷酸二氢钠为缓冲溶液电解质,通过将样品溶解在乙腈:水=2:1的样品基体中,进样时间增加到100 s来达到样品富集的效果,并考察了样品基体中乙腈浓度和进样时间对富集效果的影响,研究了用硼砂或3-环己胺-1-丙烷磺酸作为电解质、缓冲溶液pH值和有机修饰剂的加入对唾液酸检测的影响。

New compounds of the type of N--N'-(2,4-dichlorophenyloxyacetyl)-semicarbazides were synthesized by a series of reactions of preparing organic isocyanates by Curtius rearrangement with 2,4- dichloro aryloxyacetic acid hydrazide using one-pot procedures.

以芳香取代酸为原料,用Curtius重排的方法合成异氰酸酯,直接与2,4-二氯苯氧乙酰肼作用,一锅法合成了4种N-取代芳基-N'-(2,4-二氯苯氧乙酰基)氨基脲类化合物。

The ammonia was evaporated under decreasing pressure, and the precipitate was filtered off and the liquid was poured into hot saturated picric acid solution to get picrate with a yield of 85.0%. The optimum process starting from imidazole-4,5-dicarboxylic acid was: imidazole-4,5-dicarboxylic acid in acetic anhydride was refluxed to get imidazole-4-carboxylic acid, and the product was esterification in ethanol with a catalyzer of concentrated sulfuric acid to get ethyl imidazole-4-carboxylate, at last the compound above was reduced by LiAlH4 in ether at room temperature to get the target compound, the total yield of this route was 49.6%.

以4,5-二羧酸咪唑为原料的较佳工艺:1 脱羧反应:4,5-二羧酸咪唑40g,醋酐1200ml,回流10h,过滤并将滤液浓缩至干,所得固体加至50%的乙醇溶液回流,过滤并将滤液自然冷却过夜,过滤得固体;2 酯化反应:4(5)-羧酸咪唑50g,乙醇1000ml和浓硫酸60ml,加热回流2h,5%浓度NaOH溶液调节至pH=8,减压浓缩至干,加入少量水回流,自然冷却过夜并过滤得固体;3 还原反应:LiAlH410g,乙醚300ml和4(5)-羧酸咪唑乙酯28g,常温反应1.5h,小心滴加25ml水后过滤,滤渣溶于300ml甲醇中并过滤,收集所得乙醚和甲醇滤液浓缩至干,将所得固体溶于300ml乙醇中加热回流,后将溶液浓缩至约30ml,冷却并过滤得固体,该路线总收率为49.6%。

In this paper, the applications of the environmental friendly solid acid catalysts for esterification were studied and the activities of these catalysts were discussed, by which the solid acid ferric sulfate x-hydrate was used first as catalyst in the synthesis of dimethyl fumarate and ethyl chloroacetate and solid super acid SO42-/Fe2O3 was used first as catalyst in the synthesis of ethyl p-nitrobenzoate.

本文研究了对环境友好的固体酸催化剂在酯化反应中的应用,首次以固体酸Fe_2(SO_4)_3·xH_2O为催化剂合成了新型防霉剂富马酸二甲酯和化工原料氯乙酸乙酯,以固体超强酸5O_4~(2-)/Fe_2O_3为催化剂合成了医药中间体对硝基苯甲酸乙酯,并探讨了这些催化剂的催化活性。

N-(6-methyl-2-pyridine)-amino-methylene-diethyl malonate was produced by condensation reaction of 2-amino-6-methyl pyridine with ethoxymethylene diethyl malonate under optimal conditions that n(2-amino-6-methyl pyridine)∶n(ethoxymethylene diethyl malonate) is 1∶1.3, reacting time 45 min and temperature 130 ℃,the yield of this reaction was 96%,which was 6% higher than that of literature.

在250℃的反应温度下,分别以二苯醚、石蜡油和邻苯二甲酸二乙酯为热载体进行成环反应,得到4-氧-7-甲基-1,8-萘啶-3-羧酸乙酯的收率分别为88.6%、56.3%和61.2%,确定二苯醚为最佳热载体,并发现反应温度对产率的影响最大,原料配比次之,反应时间基本无影响。

In order to decrease toxicities of retinods and enhance pharmacal effects and gain the relative derivatives with better curing effect and selectivity, structures of retinoic acids were modified by inducing glycosyl groups in this paper.

方法一是在氢氧化钾存在下,以4-二甲氨基吡啶做相转移催化剂,将溴代-O-乙酰基葡萄糖(5a)、溴代-O-乙酰基木糖(5b)、溴代-O-乙酰基乳糖(5c)和溴代-O-乙酰基麦芽糖(5d)分别与异维A酸反应制得1-O-异维A酰-乙酰基单糖(6a,6b)和1-O-异维A酰-乙酰基二糖(6c,6d),收率为53~65%。

In this study, new benzo[l,2,3]thiadiazole derivatives were designed according to relationship of structure and efficacy. The 9 novel compounds were synsthesized with following reactions. The chlorine atom in 2-chloro-3,5-dinitro-benzoic acid as beginning raw material was substituted by 2-methylpropane-2-thiol, esterified then with bromoethane, reduced by iron powder and cyclized to obtain ethyl benzo[l,2,3]thiadiazole-7 after diazonation reation.

本论文根据苯并噻二唑诱导剂的构效关系设计了新的苯并噻二唑的结构,并合成了9个未见文献报道的化合物,合成步骤如下:采用2-氯-3,5-二硝基苯甲酸为起始原料,苯环上的氯原子被叔丁基硫醇置换,羧酸由溴乙烷酯化,硝基由铁粉还原,随后经重氮化关环生成苯并[1,2,3]噻二唑-7-羧酸乙酯。

L-Phenylalanine was then obtained by alkylation of N- glycine ethyl ester with benzyl bromide in the presence of an asymmetric phase-transfer catalyst-N-benzyl-cinchonine chloride, followed by hydrolysis of the resulting product.

以甘氨酸乙酯盐酸盐和二苯甲酮为起始原料合成了N-二苯亚甲氨基乙酸乙酯,后者在手性相转移催化剂-N-苄基氯化辛可宁诱导下与烷基化试剂溴化苄发生不对称相转移催化烷基化反应,水解得到L-苯丙氨酸。

The results showed 3 types of aluminum compound prepared in this paper all had good poison protection effectiveness on such impurities as stannous chloride,lead oxide,sodium hydrogen sulfate,and so on.Moreover,the mechanism of the poison of catalyst was also discussed.

结果表明,合成的3种防中毒剂即防-1、防-2(主要成分为乙酰丙酮合铝)及防-3(主要成分为二乙酰丙酮基异丙氧基铝)对二月桂酸二丁基锡、氯化亚锡、二正丁胺、硫脲、氧化铅及硫酸氢钠等杂质均有较好的防中毒作用;不同防中毒剂对不同杂质的防中毒作用有一定的选择性。

第29/40页 首页 < ... 25 26 27 28 29 30 31 32 33 ... > 尾页
推荐网络例句

Lugalbanda was a god and shepherd king of Uruk where he was worshipped for over a thousand years.

Lugalbanda 是神和被崇拜了一千年多 Uruk古埃及喜克索王朝国王。

I am coming just now,' and went on perfuming himself with Hunut, then he came and sat.

我来只是现在,'歼灭战perfuming自己与胡努特,那麼,他来到和SAT 。

The shamrock is the symbol of Ireland and of St.

三叶草是爱尔兰和圣特里克节的标志同时它的寓意是带来幸运。3片心形叶子围绕着一根断茎,深绿色。