Vieira de Castro, T.Huang, D.M.Sumby, C.J.Lawrence, A.L.George, J.H.2023-02-032023-02-032023Chemical Science, 2023; 14(4):950-9542041-65202041-6539https://hdl.handle.net/2440/137371A concise synthesis of a stereochemically complex meroterpenoid, peshawaraquinone, via the unsymmetrical dimerization of its achiral precursor, dehydro-a-lapachone, is reported. Enabled by reversible oxa-6p-electrocyclizations of 2H-pyran intermediates, the base-catalyzed dimerization sets up an intramolecular (3 + 2) cycloaddition, with the formation of six stereocenters during the cascade. Combining the generation and in situ dimerization of dehydro-a-lapachone allows a one-step total synthesis of peshawaraquinone from lawsone and prenal.en© 2023 The Author(s). Published by the Royal Society of Chemistry. Open Access Article. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.Journal article10.1039/d2sc05377b2023-02-03631954Huang, D.M. [0000-0003-2048-4500]Sumby, C.J. [0000-0002-9713-9599]George, J.H. [0000-0002-7330-2160]