摘要
From the ethanol extract of the roots of Brachystemma calycinum D. Don, a Chinese folk herb, four new minor cyclic peptides namely brachystemin A, B, C and D (1 - 4) have been isolated. Their structures were established as cyclo (Pro(1)-Phe-Leu-Ala(1)-Thr-Pro(2)-Ala(2)-Gly) (1), cyclo (Pro(1)-Ala-Phe-Trp-Asp-Pro(2)-Leu-Gly) (2), cyclo (Pro(1)-Ile-Gly-Pro(2)-Val-Ala(1)-Ala(2)-Tyr) (3) and cyclo ( Pro-OMet-Trp-Ile-Gly-Ala-Leu-Asp) (4) respectively by means of extensive spectral methods.
从中国民间草药短瓣花 (BrachystemmacalycinumD .Don)干燥根的乙醇提取物中分离得到 4个新的微量环八肽 ,命名为短瓣花环肽A、B、C和D。经光谱分析鉴定 ,它们的结构分别为cyclo (Pro1_Phe_Leu_Ala1_Thr_Pro2 _Ala2 _Gly)(1)、cyclo (Pro1_Ala_Phe_Trp_Asp_Pro2 _Leu_Gly) (2 )、cyclo (Pro1_Ile_Gly_Pro2 _Val_Ala1_Ala2 _Tyr) (3)和cyclo (Pro_OMet_Trp_Ile_Gly_Ala_Leu_Asp) (4 )。
