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Total Syntheses of (-)-Minovincine and (-)-Aspidofractinine through a Sequence of Cascade Reactions.

ABSTRACT: We report 8-step syntheses of (-)-minovincine and (-)-aspidofractinine using easily available and inexpensive reagents and catalyst. A key element of the strategy was the utilization of a sequence of cascade reactions to rapidly construct the penta- and hexacyclic frameworks. These cascade transformations included organocatalytic Michael-aldol condensation, a multistep anionic Michael-SN 2 cascade reaction, and Mannich reaction interrupted Fischer indolization. To streamline the synthetic routes, we also investigated the deliberate use of steric effect to secure various chemo- and regioselective transformations.

SUBMITTER: Varga S

PROVIDER: S-EPMC7497198 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Total Syntheses of (-)-Minovincine and (-)-Aspidofractinine through a Sequence of Cascade Reactions.

Varga Szilárd S Angyal Péter P Martin Gábor G Egyed Orsolya O Holczbauer Tamás T Soós Tibor T

Angewandte Chemie (International ed. in English) 20200603 32

We report 8-step syntheses of (-)-minovincine and (-)-aspidofractinine using easily available and inexpensive reagents and catalyst. A key element of the strategy was the utilization of a sequence of cascade reactions to rapidly construct the penta- and hexacyclic frameworks. These cascade transformations included organocatalytic Michael-aldol condensation, a multistep anionic Michael-S<sub>N</sub> 2 cascade reaction, and Mannich reaction interrupted Fischer indolization. To streamline the synth ...[more]

PMID: 32351014

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