Results
Title

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

Authors

Varga, Szilárd; Angyal, Péter; Martin, Gábor; Egyed, Orsolya; Holczbauer, Tamás; Soós, Tibor

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‐SN2 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.

Subjects

MANNICH reaction; CATALYSTS; BIOMIMETIC synthesis; CATALYSIS; CONDENSATION

Publication

Angewandte Chemie, 2020, Vol 132, Issue 32, p13649

ISSN

0044-8249

Publication type

Academic Journal

DOI

10.1002/ange.202004769