Synthesis and Solution Conformations of Cyclo(Pro–Leu–Gly)<sub>2</sub>and Cyclo(Pro–Leu–Gly)<sub>4</sub>
作者:Jun Wang、Satoshi Osada、Hiroaki Kodama、Tetsuo Kato、Michio Kondo
DOI:10.1246/bcsj.72.533
日期:1999.3
Two cyclic peptides containing the C-terminal tripeptide sequence of oxytocin, cyclo(Pro–Leu–Gly)2 and cyclo(Pro–Leu–Gly)4, have been synthesized from the corresponding linear hexapeptide active ester under high dilution conditions. Cyclo(Pro–Leu–Gly)4 serves as an example of the synthesis of cyclic peptides from linear peptides containing an even number of amino acid residues through dimerization
在高稀释条件下,由相应的线性六肽活性酯合成了两种含有催产素 C 端三肽序列的环肽,环(Pro-Leu-Gly)2 和环(Pro-Leu-Gly)4。Cyclo(Pro-Leu-Gly)4 是通过二聚化从含有偶数个氨基酸残基的线性肽合成环肽的一个例子。这两种化合物通过 TLC、HPLC、氨基酸分析、NMR 和质谱进行表征。Cyclo(Pro-Leu-Gly)2 也由线性三肽前体独立合成,其性质与线性六肽相同。圆二色性表明环(Pro-Leu-Gly)2如预期的那样含有β-转角;相比之下,cyclo(Pro-Leu-Gly)4 表现出随机的结构模式。核磁共振谱表明,环(Pro-Leu-Gly)2 在 DMSO 中仅固定在一种构象异构体中,而在 CDCl3 溶液中,存在几种具有快速相互转换的构象。...