The Macrocyclic Spermidine Alkaloid (−)-(S)-Neoperiphylline: Revision of the Structure Based on the Total Synthesis
作者:Sergey A. Sergeyev、Manfred Hesse
DOI:10.1002/hlca.200390046
日期:2003.2
The total synthesis of the two isomeric macrocyclic enamides 2 and 17 is described. The precursor 14 was synthesized by means of template-assisted macrocyclization (Scheme 2). Isomerization of 14 in the presence of [Fe(CO)5] gave 2 and 17 (Scheme 4). Structure 2 was previously assigned to the alkaloid neoperiphylline. However, the synthetic 2 showed completely different properties compared to the earlier
描述了两种异构的大环酰胺2和17的总合成。通过模板辅助的大环化反应合成前体14(方案2)。在[Fe(CO)5 ]存在下14的异构化得到2和17(流程4)。结构2先前已分配给生物碱新茶碱。然而,与天然化合物的较早描述的数据相比,合成物2表现出完全不同的特性。出人意料的是,第二合成产品的分析数据17非常接近天然新茶碱。我们得出的结论是,先前分配的新茶碱的结构是错误的,应将其校正为(-)-(4 S,12 Z)-4-苯基-9-[(2 E)-3-苯基丙-2-烯酰基] -1,5,9-三氮杂三环-12-en-2-one(17)。