作者:Dale L. Boger、Jiyong Hong、Masataka Hikota、Michio Ishida
DOI:10.1021/ja983631q
日期:1999.3.1
A concise total synthesis of phomazarin (1) is detailed enlisting a heterocyclic azadiene inverse electron demand Diels−Alder reaction (1,2,4-triazine → pyridine) for preparation of the fully substituted and appropriately functionalized pyridine C-ring. Thus, [4 + 2] cycloaddition (85%) of triethyl 1,2,4-triazine-3,5,6-tricarboxylate (2) with trimethoxyethylene (3) followed by conversion of the cycloadduct
phomazarin (1) 的简明全合成详细介绍了杂环氮杂二烯逆电子需求 Diels-Alder 反应(1,2,4-三嗪 → 吡啶),用于制备完全取代和适当功能化的吡啶 C 环。因此,1,2,4-三嗪-3,5,6-三羧酸三乙酯(2)与三甲氧基乙烯(3)的[4+2]环加成(85%),随后环加合物11转化为提供的环酐13 phomazarin C 环与三个羧酸盐适当区分。通过将芳基锂试剂 9 选择性亲核加成到 13 中受阻最小的羰基酸酐,随后 B 环的 Friedel-Crafts 闭合,A 环和 C 环的连接提供了完全功能化的 phomazarin 骨架。