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Pyrrole Strategy for the γ-Lactam-Containing Stemona Alkaloids: (±)Stemoamide, (±)Tuberostemoamide, and (±)Sessilifoliamide A.

ABSTRACT: Stemona alkaloids contain family members with diverse structural scaffolds. Many of them feature a γ-lactam ring embedded in their characteristic 5-7-5 fused tricyclic core. Herein a pyrrole strategy was developed to enable the total syntheses of three Stemona alkaloids: (±)stemoamide, (±)tuberostemoamide, and (±)sessilifoliamide A. In these cases, a substituted pyrrole was used as the γ-lactam precursor. A sequential pyrrole oxidation and enamide reduction were realized to convert the pyrrole to the corresponding γ-lactam in those three natural products. The use of a pyrrole in an early stage of the synthesis offers the advantage of rapid construction of the key intermediates by exploiting its nucleophilicity.

SUBMITTER: Yin X

PROVIDER: S-EPMC8232349 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Pyrrole Strategy for the γ-Lactam-Containing Stemona Alkaloids: (±)Stemoamide, (±)Tuberostemoamide, and (±)Sessilifoliamide A.

Yin Xianglin X Ma Kaiqing K Dong Ying Y Dai Mingji M

Organic letters 20200617 13

Stemona alkaloids contain family members with diverse structural scaffolds. Many of them feature a γ-lactam ring embedded in their characteristic 5-7-5 fused tricyclic core. Herein a pyrrole strategy was developed to enable the total syntheses of three Stemona alkaloids: (±)stemoamide, (±)tuberostemoamide, and (±)sessilifoliamide A. In these cases, a substituted pyrrole was used as the γ-lactam precursor. A sequential pyrrole oxidation and enamide reduction were realized to convert ...[more]

PMID: 32551684

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