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An oxidopyrylium cyclization/ring-opening route to polysubstituted ?-hydroxytropolones.

ABSTRACT: ?-Hydroxytropolones are a class of molecules with therapeutic potential against several human diseases. However, structure-activity relationship studies on these molecules have been limited due to a scarcity of efficient synthetic methods to access them. It is demonstrated herein that ?-hydroxytropolones can be generated through a BCl(3)-mediated ring-opening/aromatization/demethylation process on 8-oxabicyclo[3.2.1]octenes. Used in conjunction with an improved method based on established oxidopyrylium dipolar cycloadditions, several polysubstituted ?-hydroxytropolones can be accessed in three steps from readily available ?-hydroxy-?-pyrones.

SUBMITTER: Meck C

PROVIDER: S-EPMC3518617 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature

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An oxidopyrylium cyclization/ring-opening route to polysubstituted α-hydroxytropolones.

Meck Christine C Mohd Noushad N Murelli Ryan P RP

Organic letters 20121120 23

α-Hydroxytropolones are a class of molecules with therapeutic potential against several human diseases. However, structure-activity relationship studies on these molecules have been limited due to a scarcity of efficient synthetic methods to access them. It is demonstrated herein that α-hydroxytropolones can be generated through a BCl(3)-mediated ring-opening/aromatization/demethylation process on 8-oxabicyclo[3.2.1]octenes. Used in conjunction with an improved method based on established oxidop ...[more]

PMID: 23167954

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