羧化作用
- 与 羧化作用 相关的网络例句 [注:此内容来源于网络,仅供参考]
-
Then Doripenem came into the market in the July ,2005. We studied the synthesis of Doripemen.Firstly, we synthesized the chemical 2 from the starting material------o-hydroxylphenylacylamine through Reformastky reaction, alkylation, Diekmann reaction, enolization, esterification and etc. Secondly, we synthesized the chemical 3 from L — hydroxylproline through the protection of carboxyl, amidogen and hydroxyl group, reduction by NaBr, SN_2 substitution and Mitsumobu reaction.
我们以水杨酰胺为起始原料,经Reformatsky反应、烷基化、Diekmann环合、烯醇化、酯化等反应合成双环母核2;再从L-羟基脯氨酸出发,经酯化保护羧基、保护氨基、保护羟基、硼氢化还原酯得醇、Sn2取代和Mitsumobu反应等合成巯基侧链3;最后由化合物3经脱保护、水解得硫醇,和化合物2在二异丙基乙基胺的作用下缩合,最后Pd/C催化脱保护,历经16步反应最终得到产物多尼培南。
-
The results indicate that improving temperature to reflux, using low polarity solvent as dispersion medium and proper molar ratio of tetrabutyl titanate to stearic acid can bring out good modification. The function of tetrabutyl titanate is to react with the surface hydroxyl groups and adsorbed H2O on the powder particles to produce new binding sites such as M—O—Ti—OC4H9and M—O—Ti—OH, which can easily react with the carboxylic acid. As temperature increases from room temperature to reflux temperature, the reactions between RCOO- and Ti change from coordinate bonds to covalent bonds, which makes the carbon chains of stearic acids more strongly bound with the powder particles surface.
研究结果表明,提高处理温度、适当增加复合改性剂中硬脂酸的量并选用极性弱的有机溶剂可达到比较理想的改性效果;钛酸四丁酯的作用是与粉体粒子表面的羟基以及吸附水反应产生偶联点,如M—O—Ti—OH,这些偶联点易于与羧酸反应;在低温时RCOO-与偶联点的Ti之间以配合物的形式发生作用,在回流温度下处理时,主要发生酯化反应,使硬脂酸更牢固地嫁接到粉体粒子表面,改性效果更好。
-
After esterification, the ethyl-2-chloro-3-phenylpropionate reacts with diethyl malonate under the catalysis of sodium ethylate, and we obtain the corresponding triethyl ester. The-benzylsuccinic acid is formed by the triethyl ester reacting with concentrate hydrochloric acid and taking place hydrolyzation and decarboxylation reaction at the same time. In order to avoid the formation of cinnamic acid, the sodium ethylate and diethyl malonate must be react sufficiently. The course has simple operation, inexpensive materials and better yield.
具体制备工艺为:首先以L-苯丙氨酸为原料采用重氮化方法得到-2-氯-3-苯基丙酸,再经酯化得到-2-氯-3-苯基丙酸乙酯后在乙醇钠催化作用下和丙二酸二乙酯缩合,发生SN2反应,得到相应的三乙酯,然后经水解和脱羧,得到-苄基丁二酸;在实验中乙醇钠要和丙二酸二乙酯充分反应,避免生成肉桂酸乙酯;该过程操作简单,原料便宜,产率较高,总收率可达到26.8%。
-
This is exactly opposite to the order of E465/E665 in HA and the order ofΔ~ K. It shows that the larger the extent of humification, the larger the effect for reducing the rate of Phoxim hydrolysis, because the extent of HA humification is closely related to the extent of benzene in HA and the amount of carbonyl, aryl, phenolic hydroxide.
因腐殖酸腐殖化程度与腐殖酸芳构化程度、羧基、羰基和酚羟基的含量等相关,因此用腐殖酸腐殖化程度反映腐殖酸对农药水解作用大小比仅用腐殖酸中有机碳含量等因素反映更为合理。
-
PartⅡ: N-phosphoryl amino acids have many biomimic reactions and the co-participation of the three functional group of phosphoryl, carboxyl and theamino acids side chain are essential for these reactions to occur. To study themechanism and the intrinsic relationship of these three groups will enlight thestudy on the mechanism of enzymatic reaction, the origin of life and otherproblems in the life science.
第二部分:N-磷酰氨基酸的多种仿生化反应是磷酰基、羧基、和侧链基团协同作用的结果,对其反应机理的研究,将对生化反应和生命起源中磷的作用有着重要的意义。
-
After the carboxymethylation,the solubility of pachyman in the water was significantly increased,its β-D-glucan characteristic absorption peak at 890 cm-1 became weak obviously,and its methylene vibration absorption peak and CO antisymmetrical stretch vibration absorption peak appeared at 1 333 and 1 606 cm-1 respectively,which indicated that the carboxymethylation succeeded.The analysis of AFM results showed that CMP molecules existed in different morphology under different solution conditions,and that the concentration,ionic strength and solvent physical chemistry characteristics of polysaccharide solution had effects on the CMP chains conformation and the action mode between different molecular chains.The phenomena were considered to be related to hydrogen bond association and intramolecular and intermolecular electrostatic interactions of CMP.
结果表明:经过羧甲基修饰,茯苓多糖在水中的溶解性显著增加,890 cm-1 处的β-D-葡聚糖特征吸收峰明显减弱,1 333 cm-1 处出现次甲基振动吸收峰,1 606 cm-1 处出现〖JG(〗C〖ZJLX,Y〗O〖JG)〗非对称伸缩振动吸收峰,表明羧甲基化成功;原子力显微镜分析表明:在不同溶液条件下,CMP分子以不同形态存在,多糖溶液的浓度、离子强度及溶剂的物化特性均能对CMP的分子链构象及链间相互作用形式产生影响,推测可能与CMP分子内、分子间的氢键缔合及静电作用有关,CMP分子与云母基底间的吸附及静电作用也会对CMP的分子链构象及图像质量产生影响。
-
Firstly, 3-ethylthiobutanal was prepared from crotonaldehyde reacting with ethanehiol in triethylamine with high yield. Secondly, methyl acetoacetate was converted to 6-ethylthiohept-3-en-2-one by three steps via hydrolysis, condensation with 3-ethyltio-butanal and dehydration, then 6-ethylthiohept-3-en-2-one was cycloco ndensed with dimethyl malonate by Michael addition and Claisen condensation, followed by saponification and decarboxylation to give the intermediate of 5-(2-ethylthiopropyl)-cyclohexane-1,3-dione.
首先,以巴豆醛与乙硫醇为原料,在三乙胺的催化作用下高收率制得3-乙硫基丁醛;然后从乙酰乙酸甲酯出发,通过碱水解、与3-乙硫基丁醛缩合、脱水三步反应合成6-乙硫基-3-烯-2-庚酮,接着6-乙硫基-3-烯-2-庚酮与丙二酸二甲酯通过Michael加成和Claisen缩合成环,再通过皂化和脱羧反应生成中间体5-[2-丙基]-1,3-环己二酮;再与丙酸酐反应丙酰化,最后与0-3-氯-2-丙烯基羟胺肟化,得到目标化合物烯草酮。
-
Methods: A model to evaluate lymphocyte proliferation stimulated with a polyclonal activator, concanavalin A, was established by vital dye carboxyl fluorescin diacetate succinmidyl ester labeling technique. Effects of the different doses of anisomycin on the lymphocyte proliferation were estimated by flow cytometry and MTT methods. The propidium iodide labeling technique was applied to assay the effect of the different doses of anisomycin on changes of the lymphocyte cell-cycle stimulated by ConA or by phorbol ester plus Ionomycin. The percentage of the expression level of CD69 and CD25 on the activated lymphocytes was evaluated by fluorescin-conjugated monoclonal antibody double labeling technique.
以活体染料羧基荧光素乙酰乙酸琥珀酰亚胺酯染色,建立在多克隆刺激剂刀豆蛋白A刺激下评价小鼠淋巴细胞增殖的模型,通过流式细胞术和MTT法分析茴香霉素在不同剂量下对淋巴细胞增殖的作用;采用碘化丙锭染色分析茴香霉素对ConA或佛波醇酯加离子霉素刺激的小鼠淋巴细胞周期变化的作用;利用荧光标记的单克隆抗体双染技术和流式细胞术观察茴香霉素对小鼠CD3~+T细胞早期及中期活化标志分子CD69和CD25表达的影响。
-
Itamin D from the skin and diet is metabolized in the lier to 25-hydroxyitamin D (Figure 1), which is used to determine a patient's itamin D status1,2,3,4; 25-hydroxyitamin D is metabolized in the kidneys by the enzyme 25-hydroxyitamin D-1-hydroxylase (CYP27B1) to its actie form, 1,25-dihydroxyitamin D.1,2,3,4 The renal production of 1,25-dihydroxyitamin D is tightly regulated by plasma parathyroid hormone leels and serum calcium and phosphorus leels.1,2,3,4 Fibroblast growth factor 23, secreted from the bone, causes the sodium–phosphate cotransporter to be internalized by the cells of the kidney and small intestine and also suppresses 1,25-dihydroxyitamin D synthesis.5 The efficiency of the absorption of renal calcium and of intestinal calcium and phosphorus is increased in the presence of 1,25-dihydroxyitamin D (Figure 1).2,3,6 It also induces the expression of the enzyme 25-hydroxyitamin D-24-hydroxylase (CYP24), which catabolizes both 25-hydroxyitamin D and 1,25-dihydroxyitamin D into biologically inactie, water-soluble calcitroic acid.2,3,4
从皮肤和食物来的维生素D在肝中代谢为25-羟基维生素D(图1),被用来决定病人体内维生素D情况的1,2,3,4;25-羟基维生素D在肾中被25-羟基维生素D1羟化酶(CYP27B1)转变为有活性的1,25-二羟基维生素D 。1,2,3,4由肾产生1,25-二羟基维生素D是被血浆甲状旁腺激素和血清钙,磷水平紧密调节。1,2,3,4由骨分泌的成纤维细胞生长因子23使钠磷协同转运蛋白被肾和小肠细胞内化及抑制1,25-二羟维生素D合成。5 在1,25-二羟基维生素D作用下肾和小肠吸收钙及磷的效率增高(图1)。2,3,6 它也包括25-羟四- 24 -羟化酶的表达(CYP24),且将1,25二羟基维生素D和25羟基维生素D异化成无生物活性,水溶性的维生素D3-23羧酸。2,3,4
-
The result of potassium malonyloxyborohydride as a new hydroboration reagent reacts with terminal alkenes and alkynes is described.
介绍新的硼氢化试剂丙二酰氧基硼氢化钾与链端烯炔烃的作用,烯烃的硼氢化物在PTC条件下,插入∶CCl2 ,可得饱和羧酸;炔烃则难以与之硼氢化。
- 推荐网络例句
-
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。
-
Chapter Three: Type classification of DE structure in Sino-Tibetan languages.
第三章汉藏语&的&字结构的类型划分。