Seven-Step Stereodivergent Total Syntheses of Punicafolin and Macaranganin
Hiromitsu Shibayama, Y. Ueda, Takashi Tanaka, Takeo Kawabata
Abstract
The first total syntheses of punicafolin ( 1 ) and macaranganin ( 2 ) were achieved in seven steps, respectively, from commercial α- d -glucose. The characteristic features of the synthesis are (1) sequential site-selective introduction of the adequate galloyl groups into unprotected d -glucose by a catalyst-controlled manner and (2) stereodivergent construction of the 3,6-HHDP bridge by oxidative phenol coupling of a common intermediate via a ring-flipping process of the glucose core. Because no protective groups were used for glucose throughout the process, extremely short-step total syntheses of natural glycosides 1 and 2 (MW 938) were performed.
Topics & Concepts
ChemistryTotal synthesisOxidative coupling of methaneStereochemistryPhenolGlycosideCatalysisCombinatorial chemistryOrganic chemistryCarbohydrate Chemistry and SynthesisPhytochemical compounds biological activitiesPlant-derived Lignans Synthesis and Bioactivity