Construction of an Epoxy-lactone Moiety on the C/D Ring of Highly Oxygenated Triterpenes through a Modified SeO 2 -Promoted Oxidative Cyclization

作者：Chen, Yang; Li, Qiao-Yue; Xie, Xiao-Yan; Wang, Wei; Li, Dashan; Wang, Wen-Jing^*; Shao, Li-Dong^*

来源：Synthesis, 2024, 56(04): 553-560.

DOI：10.1055/a-2122-4021

• epoxy-lactone moiety
• one-step synthesis
• gram-scale
• highly oxygenated triterpene
• oxidative cyclization

We present herein a synthetic endeavor to prepare the epoxy-lactone moiety commonly present in the C/D ring of highly oxygenated triterpenes. Two strategies are applied starting from ursolic acid: (i) Br+-promoted cyclization-isomerization for late-stage epoxidation, and (ii) one-step SeO2-promoted oxidative cyclization. Additionally, the desired epoxy-lactone moiety can be readily prepared on gram scale in one step by using the modified SeO2/TBHP/AcOH oxidative system.

• 单位
  云南大学