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Total Syntheses of the Isomeric Aglain Natural Products Foveoglin?A and Perviridisin?B: Selective Excited-State Intramolecular Proton-Transfer Photocycloaddition.

ABSTRACT: Selective excited-state intramolecular proton-transfer (ESIPT) photocycloaddition of 3-hydroxyflavones with trans, trans-1,4-diphenyl-1,3-butadiene is described. Using this methodology, total syntheses of the natural products (±)-foveoglin?A and (±)-perviridisin?B were accomplished. Enantioselective ESIPT photocycloaddition using TADDOLs as chiral hydrogen-bonding additives provided access to (+)-foveoglin?A. Mechanistic studies have revealed the possibility for a photoinduced electron-transfer (PET) pathway.

SUBMITTER: Wang W

PROVIDER: S-EPMC5876029 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Total Syntheses of the Isomeric Aglain Natural Products Foveoglin A and Perviridisin B: Selective Excited-State Intramolecular Proton-Transfer Photocycloaddition.

Wang Wenyu W Clay Anthony A Krishnan Retheesh R Lajkiewicz Neil J NJ Brown Lauren E LE Sivaguru Jayaraman J Porco John A JA

Angewandte Chemie (International ed. in English) 20171013 46

Selective excited-state intramolecular proton-transfer (ESIPT) photocycloaddition of 3-hydroxyflavones with trans, trans-1,4-diphenyl-1,3-butadiene is described. Using this methodology, total syntheses of the natural products (±)-foveoglin A and (±)-perviridisin B were accomplished. Enantioselective ESIPT photocycloaddition using TADDOLs as chiral hydrogen-bonding additives provided access to (+)-foveoglin A. Mechanistic studies have revealed the possibility for a photoinduced electron-transfer ...[more]

PMID: 28950418

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