Synthetic investigations of (1,3′)-bistetrahydroisoquinolines: towards pentacyclic analogues of piperazine core alkaloids
作者:Sylvain Aubry、Stéphane Pellet-Rostaing、Bernard Fenet、Marc Lemaire
DOI:10.1016/j.tetlet.2005.12.056
日期:2006.2
lines are reported as the key intermediates for the synthesis of ecteinascidin and phthalascidin pentacyclic structure analogues through successive Pictet–Spengler cyclization and intramolecular peptide coupling. The direct Pictet–Spengler reaction between a derivative of l-DOPA and N-protected-α-aminoaldehyde was first extended to the synthesis of cis-(1,3′)-bistetrahydroisoquinoline. After introduction
(1,3')-双四氢异喹啉的合成研究据报道是通过连续的Pictet-Spengler环化作用和分子内肽偶联合成邻苯二酚和邻苯二酚五环结构类似物的关键中间体。l-DOPA衍生物与N-保护的α-氨基醛之间的直接Pictet-Spengler反应首先扩展到顺式的合成-(1,3')-双四氢异喹啉。引入所需的氨基酸部分后,有效的六元环分子内肽偶联产生了哌嗪衍生物结构。通过NMR和X射线光谱法证实了完整的结构归属。然而,N-保护的α-氨基醛的光学完整性似乎对反应条件敏感。Pentacylic结构,具有抗C3-C11骨干立体化学,从环合制得的对-和邻位-与3-OH基团的L-DOPA衍生物。