Reductive Aldol Approach to Natural Products: Bioinspired Synthesis of abeo-11(12 → 13)-Oleanane Triterpenoids

Ruoxi Li; Jingjing Wu

doi:10.1021/acs.orglett.3c02076

Reductive Aldol Approach to Natural Products: Bioinspired Synthesis of abeo-11(12 → 13)-Oleanane Triterpenoids

Org Lett. 2023 Sep 1;25(34):6278-6283. doi: 10.1021/acs.orglett.3c02076. Epub 2023 Aug 18.

Authors

Ruoxi Li¹, Jingjing Wu¹

Affiliation

¹ Frontiers Science Center for Transformative Molecules, School of Chemistry and Chemical Engineering, Zhangjiang Institute for Advanced Study, Shanghai Jiao Tong University, No. 429, Zhangheng Road, Shanghai 200213, P. R. China.

PMID: 37595290
DOI: 10.1021/acs.orglett.3c02076

Abstract

A synthesis of alstoscholarinoid B (1) and 3β-acetoxy-11α-hydroxy-11(12 → 13)abeooleanan-12-al (2) has been accomplished in 7-9 steps and 10%-16% overall yield from oleanolic acid. This synthesis featured a bioinspired SmI₂-mediated reductive aldol reaction to establish the abeo-11(12 → 13)-oleanane framework of both 1 and 2 and a retro-aldol/aldol/lactonization cascade to fully construct the skeleton of 1. Moreover, the investigation of the bioinspired aldol reaction also sheds light on the potential biogenesis of natural products.