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Total Synthesis of the Chlorinated Pentacyclic Indole Alkaloid (+)-Ambiguine G.

ABSTRACT: Reported herein is the total synthesis of (+)-ambiguine G, the first member of the chlorinated pentacyclic ambiguines to yield to chemical synthesis. The synthesis is accomplished through a convergent strategy that proceeds in 10 steps from (S)-carvone oxide. Pivotal to the concise route is the successful realization of a [4+3] cycloaddition that conjoins two easily synthesized components of the carbon framework of the natural product. Also featured in the synthesis is the efficient, diastereoselective construction of a key vinylated chloro ketone and the unprecedented, one-pot reduction-elimination-oxidation sequence that transforms an enone to an advanced hydroxylated-diene intermediate.

SUBMITTER: Hu L

PROVIDER: S-EPMC8509925 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Total Synthesis of the Chlorinated Pentacyclic Indole Alkaloid (+)-Ambiguine G.

Hu Lingbowei L Rawal Viresh H VH

Journal of the American Chemical Society 20210719 29

Reported herein is the total synthesis of (+)-ambiguine G, the first member of the chlorinated pentacyclic ambiguines to yield to chemical synthesis. The synthesis is accomplished through a convergent strategy that proceeds in 10 steps from (<i>S</i>)-carvone oxide. Pivotal to the concise route is the successful realization of a [4+3] cycloaddition that conjoins two easily synthesized components of the carbon framework of the natural product. Also featured in the synthesis is the efficient, dias ...[more]

PMID: 34279940

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