五味子的环二肽及其合成

CYCLIC DIPEPTIDES FROM SCHIZANDRA CHINENSIS AND THEIR SYNTHESES

目的：研究五味子中的环肽成分。方法：用薄层色谱，硅胶及反向ＲＰ１８硅胶柱层析色谱和谱学方法。结果：分离到３个天然的环二肽及由３个环二肽组成的一个混合物并鉴定为环（亮脯）（１），环（苯丙脯）（２）和环（苯丙亮）（３），环（苯丙缬）（４），环（苯丙异亮）（５），环（苯丙苯丙）（６），另外，合成了１４个环二肽类似物。结论：首次从五味子科植物北五味子中分离到环肽。环二肽２，６～８，１４～２０，经活性筛选表明，２，１６及１８有轻微的钙拮抗效应，１９及２０显示出增强高钾所致收缩效应。

AIM: To investigate cyclopeptides from the fruits of S.chinensis . METHODS: Use thin layer chromatography, repeated silica gel and RP 18 column chromatography together with spectra as well as synthetic methods. RESULTS: Three naturally occurring cyclic dipeptides and a mixture composed of three other new naturally occurring cyclic dipeptides were obtained. Their structures were determined as cyclo (leucyl prolyl) (1), cyclo (phenyl alanyl prolyl) (2), cyclo (phenylalanyl leucyl) (3), cyclo (phenylalanyl valyl) (4), cyclo (phenylalanyl isoleucyl) (5) and cyclo (phenylalanyl phenylalanyl) (6). In addition, fourteen analogous cyclic peptides (7～20) were synthesized. CONCLUSION: Cyclopeptides were isolated from S.chinensis (Schizandraceae) for the first time. The bioactivity of some cyclic dipeptides on the contraction of rabbit aorta strips with KCl (40 mmol·L -1 ) depolarization was tested. Cyclic dipeptides 2, 6 and 18 showed slight calcium antagonism and 19, 20 can increase the contractile effect in high concentration of potassium. Studies on the bioactivities of other cyclic dipeptides are in progress.