ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Synthesis of ( ±)-rupestine A and ( ±)-rupestine J, structural reassignment of rupestine A via ECD analysis

Paruke Aibibula, Abdullah Yusuf, Jiangyu Zhao, Bianlin Wang, Guozheng Huang, and Haji Akber Aisa

Key Laboratory of Plant Resources and Chemistry in Arid Regions, and State Key Laboratory Basis of Xinjiang Indigenous Medicinal Plants Resource Utilization, Xinjiang Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Urumqi, People’s Republic of China

E-mail: haji@ms.xjb.ac.cn

Received: 7 February 2021  Accepted: 26 May 2021

Abstract:

( ±)-rupestine A and ( ±)-rupestine J were prepared in a 13–14-step linear approach. This strategy started from 3-bromo-6-methylpicolinonitrile employing Krapcho decarboxylation, Suzuki cross-coupling, RCM reaction as key steps. The structure of rupestine A was reassigned via analyzing all enantiomers with electronic circular dichroism (ECD) spectroscopy and was further proved by synthesis of rupestine J.

Keywords: Rupestine; Guaipyridine alkaloids; Decarboxylation; Structural reassignment; Total synthesis

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-021-01721-9

Chemical Papers 75 (10) 5599–5603 (2021)