Our Group Published Challenging Terpenoid Total Synthesis in Angew. Chem. Int. Ed. as VIP and Back Cover Paper
Our group has accomplished a remarkable total synthesis of a three-decade-unsolved synthetic challenge, astellatol. This research, entitled with Total Synthesis of Astellatol, was published online as VIP (Very Important Paper) in Angew. Chem. Int. Ed on the Chinese New Year’s Eve.
In this paper, a nearly-30-year-old unanswered synthetic puzzle, astellatol, has been solved in an enantiospecific manner. The highly congested pentacyclic skeleton of this rare sesterterpenoid, which possesses a unique bicyclo[4.1.1]octane motif, ten stereocenters, a cyclobutane that contains two quaternary centers, an exo-methylene group, and a sterically encumbered isopropyl trans-hydrindane motif, makes astellatol arguably one of the most challenging targets for sesterterpenoid synthesis.
An intramolecular Pauson–Khand reaction was exploited to construct the right-hand side scaffold of this sesterterpenoid. An unprecedented reductive radical 1,6-addition, mediated by SmI2, forged the cyclobutane motif. Last, a strategic oxidation/reduction step provided not only the decisive solution for the remarkably challenging late-stage transformations but also a highly valuable unraveling of the notorious issue of trans-hydrindane synthesis. Importantly, the synthesis of astellatol showcases a rapid, scalable strategy to access diverse complex isopropyl trans-hydrindane sesterterpenoids.
The co-first authors of this paper are Dr. Zhao Nan and Dr. Yin Shuqiang. SUSTech undergraduate Chen Fang is also one of the authors. Prof. Xu Jing is the only corresponding author. The research was funded by the National Natural Science Foundation of China, 1000-Talent-Plan for Young Professionals, SZSTI and SZDRC. Xu and his research group gratefully acknowledge the support from SUSTech and President Shiyi Chen, for providing a world-class research platform.
The Cover is presented as a paper-cutting style, since it’s a long-standing tradition in China, especially during the Spring Festival time. The Chinese character 福 means blessing and happiness and the character "春" means spring.