Conformationally restricted, orthogonally protected 2,4-diaminocarboxylates with a cyclopentane skeleton were efficiently synthesized from β-lactam 6, the syntheses involving strategies of diastereoselective epoxidation of the β-lactam and the corresponding monoprotected amino esters with opposite selectivities followed by regioselective opening of the oxirane ring with sodium azide. The enantiomers
从β-内酰胺6有效地合成了具有
环戊烷骨架的构象受限,正交保护的2,4-二
氨基
羧酸酯,该合成涉及β-内酰胺的非对映选择性环氧化和相应的具有相反选择性的单保护的
氨基酯的策略,然后区域选择性地开放
环氧乙烷环与
叠氮化
钠。还制备了对映体。这类新化合物不仅可以视为构象受限的β,γ-二
氨基酸衍
生物,而且还可以视为潜在的功能化碳环核苷前体。