2-Nitrophenyl Isocyanide as a Versatile Convertible Isocyanide: Rapid Access to a Fused γ-Lactam β-Lactone Bicycle
作者:Cynthia B. Gilley、Yoshihisa Kobayashi
DOI:10.1021/jo800486k
日期:2008.6.1
2-Nitrophenyl isocyanide is introduced as a convertible isocyanide with demonstration of its feasibility and applicability in an efficient synthesis of the fused γ-lactam β-lactone bicycle of proteasome inhibitor omuralide. Starting from a linear keto acid precursor, the fused γ-lactam β-lactone bicycle was prepared in four steps by a sequential biscyclization strategy; a stereocontrolled Ugi reaction
引入2-硝基苯基异氰酸酯作为可转换的异氰酸酯,证明了其在蛋白酶体抑制剂omuralide的稠合γ-内酰胺β-内酯自行车的高效合成中的可行性和适用性。从线性的酮酸前体开始,通过顺序双环化策略分四个步骤制备了融合的γ-内酰胺β-内酯自行车。N-酰基苯并三唑中间体形成后,进行立体控制的Ugi反应和随之而来的直接β-内酯化。所述Ñ -acylbenzotriazole服从于帧内或从各种用碱催化量的亲核试剂的分子间攻击以形成焦谷氨酸衍生物。