In this study, we accomplished a de novo synthesis of bisindole alkaloid geissolosimine. Geissoschizoline, the north fragment of geissolosimine was first prepared in 15 steps (longest linear sequence, LLS) by leveraging catalytic asymmetric double Michael addition, which also highlights a domino oxidation/intramolecular condensation and an unprecedented SnCl4/TFA-promoted deprotection/isomerization/intramolecular cyclization cascade. The biomimetic union of geissoschizoline with vellosimine was successively realized under the influence of (±)-CSA, enabling the synthesis of geissolosimine. Additionally, this innovative strategy also provided as a concise access to akuammicine and the bio-inspired transformation of akuammicine via (16S)-deshydroxymethylstemmadenine to condylocarpine and iso-condylocarpine was also demonstrated.

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