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qq8489金虫 (小有名气)
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求助一些英文翻译成中文，不胜感激啊！50个金币先奉上，翻译专业的，再送上50个金币。
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4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride was isolated and fully characterized.90,93 It is a stable compound that can be stored in the solid state at room temperature for up to a month or for several months in the refrigerator, without detectable decomposition. This reagent combined with carboxylic acid gave an active ester 21 (Scheme 19), and was used as condensing reagent for synthesis of esters and amides.94–96 Taddei97 reported the application of DMTMM to the solidphase synthesis of peptides. The yields and purity of the products were high.Recently, Kaminski et al.98 introduced 4-(4,6-dimethoxy- 1,3,5-triazin-2-yl)-4-methylmorpholinium tetrafluoroborate as a more stable reagent than the corresponding DMTMM chloride. The new coupling reagent was used in ester and peptide synthesis, in solution, and in solid-phase synthesis. DMTMM 21 (Scheme 20) can be generated by different protocols mentioned above. This active ester, without isolation was used for many transformation of carboxylic group. Giacomelli et al.99 prepared it using CDMTand applied it to the synthesis of N-methoxy-N-methylamides, commonly named Weinreb amides 22 (Scheme 20), a useful precursor to ketones.100 A variety of these compounds were obtained quantitatively from carboxylic acids, and N-protected amino acids with high yields and purity.DMTMMwas also used for this purpose, but the yields of Weinreb amides were lower. It was reported that active ester 21 (Scheme 20), prepared from DMTMM was reduced by hydrogen and Pt/C as the catalyst to the corresponding aldehyde 23 (Scheme 20) in good yields.101 Required optimization of the solvent, hydrogen pressure, temperature, and time of reduction are disadvantages to this method. Higher hydrogen pressure (5 atm) gave alcohols. Activated esters of aromatic carboxylic acid, and N-Boc or N-Z protected a-amino acids were converted to ketones 25 (Scheme 20) or a-amino ketones by Grignard reagent in the presence of stoichiometric amounts of CuI.102 Bandar and Pandit103 reported the synthesis of 2-oxazolines 26 (Scheme 20) from acyloxy triazine. The active ester was reacted at room temperature with 2-amino-2-methyl-1-propanol giving the desired product with good yields. The same conditions, were used for the selective preparation of monoacylated piperazine derivatives 27 (Scheme 20) with good yields.104 Monoacylation of symmetrical diamines often becomes problematic due to competitive bisacylation. Recently, active ester 21 of formic acid was used for the formylation of amines and a-amino acid esters 28 (Scheme 20). The reaction was conducted under reflux in methylene chloride, or under microwave irradiation to reduce the reaction time from hours to a few minutes. The yields were high, the products pure and no significant racemization of the chiral centers was observed. Based on the reactivity of CC, Kunishima et al.106 published preliminary data about a new immobilized dehydrocondensing reagent in a polymerized form (Fig. 7). This polymer reacts with carboxylic acids, in the presence of a NMM like CDMT or DMTMM, giving active esters, which with amines, gave amides in good yields. |
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qq8489(金币+50, 翻译EPI+1): 2011-04-20 22:53:23
ringzhu(翻译EPI-1): 机器翻译 收回EPI 2011-04-21 20:18:38
ringzhu(翻译EPI-1): 机器翻译 收回EPI 2011-04-21 20:18:38
| 4 - （4,6 -二甲氧基- 1 ,3,5 -三嗪- 2 -基）- 4 - methylmorpholinium氯化物分离，充分characterized.90，93这是一个稳定的化合物，可以在室温固态存储温度达一个月或几个月的冰箱没有检出分解。与羧酸结合本试剂介绍了活性酯21（计划19），被称为凝合成酯和amides.94 - 96 Taddei97报道了DMTMM应用在固相多肽合成试剂。的产量和产品纯度high.Recently，卡明斯基等al.98介绍了4 - （4,6 -二甲氧基1,3,5三嗪- 2 -基）- 4 - methylmorpholinium四氟试剂作为一种更稳定的比相应的DMTMM氯化物。新的耦合试剂用于酯和肽合成，在溶液中，并在固相合成。 DMTMM 21（计划20）可以产生上述不同的协议。这种活性酯，无隔离是用于羧基许多转变。贾科梅利等al.99准备使用CDMTand它应用到了N -甲氧基- N - methylamides合成，俗称酰胺22（计划20），一个有用的前奏ketones.100这些化合物分别获得各种魏因勒卜羧酸定量酸，并与高产量和purity.DMTMMwas的N -保护氨基酸也用于此目的，但魏因勒卜酰胺的产量较低。据报道，活性酯21（图20），从DMTMM制备了氢和Pt / C减少，因为在良好的yields.101的溶剂，氢气压力，温度需要优化的催化剂，相应的醛23（计划20）和还原时间是这种方法的缺点。高等教育氢气压力（5大气压）给醇。激活的芳香羧酸酯和N -叔丁氧或新西兰保护的，由氨基酸转化格氏试剂酮25（计划20）或A -氨基酮在对CuI.102班达尔和Pandit103存在计量金额报告合成2 -唑啉26酰氧基三嗪（图20）。主动酯在室温下反应2 -氨基- 2 -甲基- 1 -丙醇给予所需的产品和良好的收益。 ，同样的条件，对于monoacylated哌嗪衍生物具有良好yields.104 27二胺Monoacylation对称（图20）用于编制往往成为选择的问题由于竞争bisacylation。最近，主动酯甲酸21是用于胺和A -氨基酸酯28（计划20）甲酰化。该反应在回流下进行甲基氯化物，或在微波辐射下，以减少反应时间从几小时到几分钟。产量分别为高，产品纯正，无手性中心的显着消旋进行了观察。关于对CC的反应的基础上，Kunishima等al.106发表了关于新的固定在一个聚合形式（图7）dehydrocondensing试剂的初步数据。这种聚合物与羧酸反应，在一个像CDMT或DMTMM数值模式匹配的存在，使活性酯，与胺，酰胺了良好收益。 |
2楼2011-04-19 18:39:52
