A Concise Route for the Synthesis of Tetracyclic Meroterpenoids: (±)-Aureol Preparation and Mechanistic Interpretation
Department of Chemical Engineering, Escuela Politécnica Superior, University of Sevilla, 41011 Sevilla, Spain
Department of Electricity and Electronics, University of Valladolid, 47011 Valladolid, Spain
Organic Chemistry, CeiA3, University of Almería, 04120 Almería, Spain
Author to whom correspondence should be addressed.
Mar. Drugs 2020, 18(9), 441; https://doi.org/10.3390/md18090441
Received: 30 July 2020 / Revised: 23 August 2020 / Accepted: 25 August 2020 / Published: 26 August 2020
(This article belongs to the Special Issue Synthesis of Marine Natural Products and Molecules Inspired by Marine Substances)
A new concise general methodology for the synthesis of different tetracyclic meroterpenoids is reported: (±)-aureol (1), the key intermediate of this general route. The synthesis of (±)-aureol (1) was achieved in seven steps (28% overall yield) from (±)-albicanol. The key steps of this route include a C–C bond-forming reaction between (±)-albicanal and a lithiated arene unit and a rearrangement involving 1,2-hydride and 1,2-methyl shifts promoted by BF3•Et2O as activator and water as initiator.