Cun Zhang, Bianlin Wang, Paruke Aibibula, Jiangyu Zhao and Haji Akber Aisa
Org. Biomol. Chem., 2021,19, 7081-7084
DOI:
10.1039/D1OB01299A,
Paper
Guaipyridine alkaloids (−)-rupestine D, (−)-guaipyridine, (−)-epiguaipyridine, and (−)-cananodine together with two stereoisomers 8-epi-rupestine D and 5-epi-cananodine were synthesized enantioselectively from readily available citronellol. The key steps in this synthesis are (i) intermolecular opening of a trisubstituted epoxide for the formation of a chiral center at C-8; (ii) ring-closing metathesis for the construction of a seven-membered carbocyclic ring; and (iii) biomimetic cyclization of a 1,5-dicarbonyl compound for the construction of a pyridine-fused bicyclic skeleton.