牛心番荔枝种子中两种异番荔素的化学结构研究

STUDIES ON CHEMICAL STRUCTURES OF TWO ISO-ACETOGENINS FROM ANNONA RETICULATA

摘要: 从牛心番荔枝Annona reticulata L.种子中分得两个番荔素( Annonaceous acetogenin):Squamone(1)和Isoannonareticin(2)。经制备TLC分离,将1和2的乙酰化物1a和2a分离得到两对2-位差向异构体:2,4-cis-Squamonediacetate(1a-1),2,4-trans-Squamonediacetate(1a-2),2,4-cis-Isoannonareticin diacetate(2a-1)和2,4-trans-Isoannonareticindiacetate(2a-2)。其中2,4-顺式体的1-1和2-1是新的番荔素成分。根据光谱(¹H-¹HCOSY,NOE)数椐分析,阐明它们的结构和相对立体化学。

Abstract: Two annonaceous acetogenins: squamone (1) and isoannonareticin (2) have been isolated from the seeds of Annona reticulata L. (Annonaceae). 1 and 2 were shown to be mixtures of 2-epimers by the successful separation of their acetates with preparative TLC, giving: 2,4-cis-squamone diacetate (1a-1), 2,4-trans-squamone diacetate (1a-2), 2,4-cis-isoannonareticin diacetate (2a-1) and 2,4-trans-isoannonareticin diacetate (2a-2). The 2,4-cis-squamone (1-1) and 2,4-trans-isoannonareticin (2-1) are new annonaceous acetogenins. Their structures and relative stereochemistry were elucidated on the basis of spectral analysis (¹H-¹H COSY and NOE).