A general strategy for the synthesis of novel, orthogonally protected scaffolds based on the unique 2-oxa-5-azabicyclo[4.1.0]heptane structure is presented. The described reaction sequence takes advantage of easily available starting materials such as serine and threonine and leads to stereochemically dense structures in few, high-yielding synthetic steps. We show how the stereochemistry can be easily tuned by starting from different β-hydroxy-α-amino acids and also by means of a transition metal-catalyzed cyclopropanation step. The compounds find application as constrained templates for the construction of geometrically diversified libraries of compounds.
提出了一种合成新型正交保护支架的一般策略,该支架基于独特的2-氧-5-氮
双环[4.1.0]庚烷结构。所述反应序列利用了易于获得的起始材料,如
丝氨酸和苏
氨酸,并且在少量高产率的合成步骤中生成了立体
化学密集的结构。我们展示了如何通过从不同的β-羟基-
α-氨基酸出发以及通过过渡
金属催化的环
丙烯化步骤,轻松调节立体
化学。所合成的化合物可作为受限模板,用于构建几何多样性的化合物库。