Resolution of (1R,2R)- and (1S,2S)-cyclic constrained phenylalanine analogues (c6Phe). Conformations of (1R,2R)- and (1S,2S)-c6Phe containing peptides
作者:Alberto Avenoza、Jesús H. Busto、Carlos Cativiela、Jesús M. Peregrina、Fernando Rodríguez
DOI:10.1016/s0040-4020(98)00692-9
日期:1998.9
synthesis. The conformational analysis, in solution, of these peptides revealed that dipeptide 3a shows an extended-type conformation, while dipeptide 3b shows a type I β-turn geometry. In addition, we have prepared the unsaturated peptides 11a and 11b and the structure of 11b, determined by X-ray analysis, also shows a type I β-turn conformation in the solid state. The NMR data of this dipeptide (11b) allowed
通过描述的拆分方法以高收率合成了对映体纯的(1 R,2 R)-和(1 S,2 S)-1-氨基-2-苯基环己烷-1-甲酸(c 6 Phe)3a和3b由Obrecht。该方法涉及非对映异构体肽7a和7b的形成,然后进行色谱分离。游离的(1 R,2 R)-和(1 S,2 S)-c 6 Phe氨基酸(3a和3b)将其转化成适当保护的苯丙氨酸类似物10a和10b,以用于肽合成。这些肽在溶液中的构象分析表明,二肽3a显示出扩展型构象,而二肽3b显示出I型β转角几何形状。另外,我们已经制备了不饱和肽11a和11b,并且通过X射线分析确定的11b的结构在固态下也显示出I型β-转角构象。该二肽的NMR数据(11b)可以表征溶液中的I型β-转角构象,并确定其与固态结构相似。这些结果表明,根据其绝对构型,c 6 Phe可以用作稳定I型β-转角或肽中延伸链的基础。