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Asymmetric Synthesis of Griffipavixanthone Employing a Chiral Phosphoric Acid-Catalyzed Cycloaddition.

ABSTRACT: Asymmetric synthesis of the biologically active xanthone dimer griffipavixanthone is reported along with its absolute stereochemistry determination. Synthesis of the natural product is accomplished via dimerization of a p-quinone methide using a chiral phosphoric acid catalyst to afford a protected precursor in excellent diastereo- and enantioselectivity. Mechanistic studies, including an unbiased computational investigation of chiral ion-pairs using parallel tempering, were performed in order to probe the mode of asymmetric induction.

SUBMITTER: Smith MJ

PROVIDER: S-EPMC6475489 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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