作者:Peter A. Jacobi、Kyungae Lee
DOI:10.1021/ja994214w
日期:2000.5.1
(±)-Stemoamide (1) was prepared in seven steps beginning with γ-chlorobutryl chloride (20) and succinimide (15), which were efficiently converted to the key alkyne oxazole 17 on a multigram scale. Intramolecular (Diels−Alder)−(retro-Diels−Alder) reaction of 17 then gave butenolide 12b directly upon aqueous workup. The remaining two stereocenters in 1 were established in a single step by a highly selective
(±)-Stemoamide (1) 从 γ-氯丁酰氯 (20) 和琥珀酰亚胺 (15) 开始,分七个步骤制备,它们以多克规模有效转化为关键的炔恶唑 17。17的分子内(Diels-Alder)-(retro-Diels-Alder)反应然后在水处理后直接得到丁烯内酯12b。1 中的其余两个立体中心是通过高度选择性还原 12b (NaBH4/NiCl2) 一步建立的,然后平衡到热力学有利的自然构型。以类似的方式从 l-焦谷氨酸 (S-35) 开始制备 (-)-stemoamide (1)。