β-Lactams as building blocks in the synthesis of macrocyclic spermine and spermidine alkaloids
作者:Harry H Wasserman、Haruo Matsuyama、Ralph P Robinson
DOI:10.1016/s0040-4020(02)00731-7
日期:2002.8
Syntheses of the macrocyclic spermidine alkaloids (±)-celacinnine (1) and (±)-dihydroperiphylline (2) as well as the related spermine alkaloid (±)-verbascenine (3) were accomplished by means of sequential ring expansions of smaller lactam rings. Three ring expansion methods were employed: (1) transamidation of N-(aminoalkyl)lactams, (2) β-lactam-lactim ether condensation followed by reductive cleavage
大环亚精胺生物碱(±)-celacinnine(1)和(±)-二氢茶碱(2)以及相关的亚精胺生物碱(±)-verbascenine(3)的合成是通过较小内酰胺环的连续环扩展来完成的。使用了三种扩环方法:(1)N-(氨基烷基)内酰胺的转酰胺基化,(2)β-内酰胺-内酰胺醚缩合,然后用NaBH 3 CN / AcOH还原双环4-氧代四氢嘧啶产物和(3)形成双环酰基肼,然后用Na / NH 3裂解N–N键。每个合成均以4-苯基氮杂环丁烷-2-酮中间体的扩环为特征,该中间体会发生酰胺基扩环或内酰胺醚缩合反应。