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Total Syntheses of Bisdehydroneostemoninine and Bisdehydrostemoninine by Catalytic Carbonylative Spirolactonization.

ABSTRACT: The first total syntheses of the stemona alkaloids bisdehydroneostemoninine and bisdehydrostemoninine in racemic forms have been achieved. The synthetic strategy features a novel palladium-catalyzed carbonylative spirolactonization of a hydroxycyclopropanol to rapidly construct the oxaspirolactone moiety. It also features a Lewis acid promoted tandem Friedel-Crafts cyclization and lactonization to form the 5-7-5 tricyclic core of the target stemona alkaloids.

SUBMITTER: Ma K

PROVIDER: S-EPMC6459687 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Total Syntheses of Bisdehydroneostemoninine and Bisdehydrostemoninine by Catalytic Carbonylative Spirolactonization.

Ma Kaiqing K Yin Xianglin X Dai Mingji M

Angewandte Chemie (International ed. in English) 20181018 46

The first total syntheses of the stemona alkaloids bisdehydroneostemoninine and bisdehydrostemoninine in racemic forms have been achieved. The synthetic strategy features a novel palladium-catalyzed carbonylative spirolactonization of a hydroxycyclopropanol to rapidly construct the oxaspirolactone moiety. It also features a Lewis acid promoted tandem Friedel-Crafts cyclization and lactonization to form the 5-7-5 tricyclic core of the target stemona alkaloids. ...[more]

PMID: 30230670

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