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Unified Synthesis of Polycyclic Alkaloids by Complementary Carbonyl Activation*.

ABSTRACT: A complementary dual carbonyl activation strategy for the synthesis of polycyclic alkaloids has been developed. Successful applications include the synthesis of tetracyclic alkaloids harmalanine and harmalacinine, pentacyclic indoloquinolizidine alkaloid nortetoyobyrine, and octacyclic β-carboline alkaloid peganumine A. The latter synthesis features a protecting-group-free assembly and an asymmetric disulfonimide-catalyzed cyclization. Furthermore, formal syntheses of hirsutine, deplancheine, 10-desbromoarborescidine A, and oxindole alkaloids rhynchophylline and isorhynchophylline have been achieved. Finally, a concise synthesis of berberine alkaloid ilicifoline B was completed.

SUBMITTER: He G

PROVIDER: S-EPMC8252720 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Unified Synthesis of Polycyclic Alkaloids by Complementary Carbonyl Activation*.

He Guoli G List Benjamin B Christmann Mathias M

Angewandte Chemie (International ed. in English) 20210501 24

A complementary dual carbonyl activation strategy for the synthesis of polycyclic alkaloids has been developed. Successful applications include the synthesis of tetracyclic alkaloids harmalanine and harmalacinine, pentacyclic indoloquinolizidine alkaloid nortetoyobyrine, and octacyclic β-carboline alkaloid peganumine A. The latter synthesis features a protecting-group-free assembly and an asymmetric disulfonimide-catalyzed cyclization. Furthermore, formal syntheses of hirsutine, deplancheine, 10 ...[more]

PMID: 33769684

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