Asymmetric Synthesis of Nidulalin A and Nidulaxanthone A: Selective Carbonyl Desaturation Using an Oxoammonium Salt DOI Creative Commons
Kaijie Ji, Richard P. Johnson, James McNeely

et al.

Published: Jan. 10, 2024

Nidulaxanthone A is a dimeric, dihydroxanthone natural product which was isolated in 2020 from Aspergillus sp. Structur-ally, the compound features an unprecedented heptacyclic 6/6/6/6/6/6/6 ring system unusual for xanthone dimers. Biosynthetically, nidulaxanthone originates monomer nidulalin via stereoselective Diels-Alder dimeri-zation. To expedite synthesis of and study proposed dimerization, we developed methodology involving use allyl triflate chromone ester activation followed by vinylogous addition to rapidly forge scaffold four-step sequence also ketone desaturation using Bobbitt’s oxoammonium salt. The asymmetric achieved acylative kinetic resolution (AKR) chiral, racemic 2H-nidulalin A. Dimerization en-antioenriched solvent-free, thermolytic conditions. Computational studies have been conducted probe both (4+2) dimerization events.

Language: Английский

Asymmetric Synthesis of Nidulalin A and Nidulaxanthone A: Selective Carbonyl Desaturation Using an Oxoammonium Salt DOI Creative Commons
Kaijie Ji, Richard P. Johnson, James McNeely

et al.

Published: Jan. 10, 2024

Nidulaxanthone A is a dimeric, dihydroxanthone natural product which was isolated in 2020 from Aspergillus sp. Structur-ally, the compound features an unprecedented heptacyclic 6/6/6/6/6/6/6 ring system unusual for xanthone dimers. Biosynthetically, nidulaxanthone originates monomer nidulalin via stereoselective Diels-Alder dimeri-zation. To expedite synthesis of and study proposed dimerization, we developed methodology involving use allyl triflate chromone ester activation followed by vinylogous addition to rapidly forge scaffold four-step sequence also ketone desaturation using Bobbitt’s oxoammonium salt. The asymmetric achieved acylative kinetic resolution (AKR) chiral, racemic 2H-nidulalin A. Dimerization en-antioenriched solvent-free, thermolytic conditions. Computational studies have been conducted probe both (4+2) dimerization events.

Language: Английский

Citations

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