Owing to having very strong bioactivity, oligo-peptides can be used as the medication or the pre-medication and become the studying focus now. Existing methods for synthesizing oligo-peptides included liquid phase pep...Owing to having very strong bioactivity, oligo-peptides can be used as the medication or the pre-medication and become the studying focus now. Existing methods for synthesizing oligo-peptides included liquid phase peptide synthesis, solid phase peptide synthesis and enzymatic peptide synthesis. In this paper, a new method for synthesizing oligo-peptides by phosphorus oxychloride activation was reported. With the assistance of phosphorus oxychloride, the phosphorylation of L-valine could take place and then was assembled into oligo-peptides, which were analyzed by electrospray ionization mass spectrometry(ESI-MS). On quenching with methanol, the reaction mixtures, which were produced under different reaction conditions, yielded the corresponding peptide methyl esters. Moreover, we found that, as the reaction conditions such as reaction time, solvent and temperature were changed, the length of peptides changed. And the length of peptides could be controlled by changing the reaction conditions.展开更多
文摘Owing to having very strong bioactivity, oligo-peptides can be used as the medication or the pre-medication and become the studying focus now. Existing methods for synthesizing oligo-peptides included liquid phase peptide synthesis, solid phase peptide synthesis and enzymatic peptide synthesis. In this paper, a new method for synthesizing oligo-peptides by phosphorus oxychloride activation was reported. With the assistance of phosphorus oxychloride, the phosphorylation of L-valine could take place and then was assembled into oligo-peptides, which were analyzed by electrospray ionization mass spectrometry(ESI-MS). On quenching with methanol, the reaction mixtures, which were produced under different reaction conditions, yielded the corresponding peptide methyl esters. Moreover, we found that, as the reaction conditions such as reaction time, solvent and temperature were changed, the length of peptides changed. And the length of peptides could be controlled by changing the reaction conditions.
文摘采用控制酯化率和不外加相转移催化剂、在敞开体系中自催化磺化反应的方法,合成了4种不同乙氧基加成数 n(n=3,5,7,9。下同)的阴离子表面活性剂月桂醇聚氧乙烯醚(LEO_n)己基琥珀酸混合双酯磺酸钠(LHSS_n)。对由4种 LEO_n 来分别合成 LHSS_n 的最佳工艺条件与 LEO_n 的乙氧基加成数的关系进行了研究。结果表明:随着乙氧基加成数的增加,单酯化反应的酯化率达到约100%时的反应温度从90℃增加到140℃;双酯化率达到约95%时的反应温度从140℃增加到170℃,己醇过量从100%增加到400%。同样地随着乙氧基加成数的增加,磺化剂亚硫酸氢钠过量从5%增加到10%,反应时间从2.25 h 增加到2.75 h,反应温度从130℃增加到180℃。从酯化反应中 LEO 进攻羰基 C 的空间位阻对酯化反应的影响以及磺化反应中产物自催化作用对磺化反应的影响分别解释了反应性变化的原因。
