Ji, KaijieJohnson, Richard P.McNeely, JamesAl Faruk, MdPorco, John A.2024-06-062024-06-062024-02-21K. Ji, R.P. Johnson, J. McNeely, M. Al Faruk, J.A. Porco. 2024. "Asymmetric Synthesis of Nidulalin A and Nidulaxanthone A: Selective Carbonyl Desaturation Using an Oxoammonium Salt." Journal of the American Chemical Society, Volume 146, Issue 7, pp.4892-4902. https://doi.org/10.1021/jacs.3c138640002-78631520-5126https://hdl.handle.net/2144/48988Nidulaxanthone A is a dimeric, dihydroxanthone natural product that was isolated in 2020 from Aspergillus sp. Structurally, the compound features an unprecedented heptacyclic 6/6/6/6/6/6/6 ring system which is unusual for natural xanthone dimers. Biosynthetically, nidulaxanthone A originates from the monomer nidulalin A via stereoselective Diels-Alder dimerization. To expedite the synthesis of nidulalin A and study the proposed dimerization, we developed methodology involving the use of allyl triflate for chromone ester activation, followed by vinylogous addition, to rapidly forge the nidulalin A scaffold in a four-step sequence which also features ketone desaturation using Bobbitt's oxoammonium salt. An asymmetric synthesis of nidulalin A was achieved using acylative kinetic resolution (AKR) of chiral, racemic 2H-nidulalin A. Dimerization of enantioenriched nidulalin A to nidulaxanthone A was achieved using solvent-free, thermolytic conditions. Computational studies have been conducted to probe both the oxoammonium-mediated desaturation and (4 + 2) dimerization events.p. 4892-4902Print-ElectronicenChemical sciencesGeneral chemistryEngineeringKetonesXanthinesSodium chlorideDimerizationArticle2024-06-0410.1021/jacs.3c138640000-0002-2991-5680 (Porco, John A)895425