Asymmetric Synthesis of the Fully Elaborated Pyrrolidinone Core of Oxazolomycin A

The asymmetric synthesis of the key pyrrolidinone core, including a highly elaborated exocyclic carbon chain, of the γ-lactam β-lactone antibiotic oxazolomycin A is described. Principal features include the Birch reduction of an aromatic pyrrole nucleus, a late stage RuO4 catalyzed pyrrolidine oxidation, and a highly diastereoselective organocerium addition to an aldehyde.本文报道了γ-内酰胺β-内酯类抗生素恶唑霉素A（oxazolomycin A）的关键吡咯烷酮母核（包含高度修饰的外环碳链）的不对称合成。该合成的核心特征包括：芳香吡咯环的伯奇还原反应、后期阶段的四氧化钌（RuO₄）催化吡咯烷氧化反应，以及针对醛基的高非对映选择性有机铈加成反应。