CYCLIC DIPEPTIDES FROM SCHIZANDRA CHINENSIS AND THEIR SYNTHESES
Wang Youchu(Wang YC), Zhou Jun(Zhou J), Tan Ninghua(Tan NH), Ding Zhongtao(Ding ZT) and Jiang Xin(Jiang X) (Laboratory of Phytochemistry, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204)
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.
【CateGory Index】： R284.3