Chemistry of Tetrahydro-1,3-oxazin-2-one: New Method for the Synthesis of Indoloquinlizidine Derivatives.
作者:Takushi KURIHARA、Yumi SOKAWA、Kayo YOKODE、Hirofumi OHISHI、Shinya HARUSAWA、Ryuji YONEDA
DOI:10.1248/cpb.39.3157
日期:——
The aldol condensation of the N-Boc-tetrahydro-β-carboline-1-acetate (4) with acrolein in the presence of lithium diisopropylamide (LDA) gave an allyl alcohol (6), which was then treated with methanesulfonyl chloride and triethylamine to give a mixture of the mesylate (8) (55%) and the indolopyrido-3, 5-oxyazin-4-one (10) (14%). When 8 was treated with 1, 8-diazabicyclo[5.4.0.]-7-undecene (DBU) in dimethylsulfoxide (DMSO) at room temperature, the azetopyridoindoles (12 and 13) were obtained unexpectedly. Alternative preparation of the indolopyrido-3, 5-oxazin-4-ones (15 and 16), which are stereoisomers of 10, from 6 followed by heating with DBU in DMSO gave several indoloquinolizidines (18, 19 and 20), which are key intermediates for the synthesis of the indole alkaloids vindolosine and vindoline.
在二异丙基酰胺锂(LDA)存在下,N-叔丁氧羰基四氢-β-咔啉-1-乙酸酯(4)与丙烯醛发生醛醇缩合反应,生成烯丙基醇(6),然后用甲磺酰氯和三乙胺处理,得到甲磺酸盐(8)(55%)和吲哚吡啶-3,5-氧嗪-4-酮(10)(14%)的混合物。室温下,用 1,8-二氮杂双环[5.4.0.]-7-十一烯(DBU)在二甲基亚砜(DMSO)中处理 8,意外地得到了氮杂环吡啶吲哚(12 和 13)。由 6 与 DBU 在二甲基亚砜(DMSO)中加热制备吲哚吡啶-3,5-恶嗪-4-酮(15 和 16)(10 的立体异构体)的另一种方法得到了几种吲哚喹嗪类化合物(18、19 和 20),它们是合成吲哚生物碱吲哚洛新和吲哚啉的关键中间体。