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Regiodivergent Photocyclization of Dearomatized Acylphloroglucinols: Asymmetric Syntheses of (-)-Nemorosone and (-)-6-epi-Garcimultiflorone A.

ABSTRACT: Regiodivergent photocyclization of dearomatized acylphloroglucinol substrates has been developed to produce type A polycyclic polyprenylated acylphloroglucinol (PPAP) derivatives using an excited-state intramolecular proton transfer (ESIPT) process. Using this strategy, we achieved the enantioselective total syntheses of the type A PPAPs (-)-nemorosone and (-)-6-epi-garcimultiflorone A. Diverse photocyclization substrates have been investigated leading to divergent photocyclization processes as a function of tether length. Photophysical studies were performed, and photocyclization mechanisms were proposed based on investigation of various substrates as well as deuterium-labeling experiments.

SUBMITTER: Wen S

PROVIDER: S-EPMC6659400 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Regiodivergent Photocyclization of Dearomatized Acylphloroglucinols: Asymmetric Syntheses of (-)-Nemorosone and (-)-6-<i>epi</i>-Garcimultiflorone A.

Wen Saishuai S Boyce Jonathan H JH Kandappa Sunil K SK Sivaguru Jayaraman J Porco John A JA

Journal of the American Chemical Society 20190702 28

Regiodivergent photocyclization of dearomatized acylphloroglucinol substrates has been developed to produce type A polycyclic polyprenylated acylphloroglucinol (PPAP) derivatives using an excited-state intramolecular proton transfer (ESIPT) process. Using this strategy, we achieved the enantioselective total syntheses of the type A PPAPs (-)-nemorosone and (-)-6-<i>epi</i>-garcimultiflorone A. Diverse photocyclization substrates have been investigated leading to divergent photocyclization proces ...[more]

PMID: 31264859

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