Total Synthesis of Anticancer Pacharin, Bauhiniastatin 4, and Bauhinoxepins C and D

Abstract

Reported herein is the total synthesis of anticancer pacharin, bauhiniastatin 4, and bauhinoxepins C and D. The synthetic strategy features a cascade reaction involving intermolecular nucleophilic aromatic substitution followed by intramolecular Knoevenagel condensation to form a dibenzo[b,f]oxepine scaffold of these compounds. Pacharin and bauhiniastatin 4 were synthesized in eight steps from 2-methylresorcinol with overall yields of 5.4% and 8.3%, respectively. Similarly, bauhinoxepins C and D were synthesized in seven steps with overall yields of 3.5% and 2.6%, respectively. This methodology offers an efficient route for accessing these natural products with implications for medicinal and synthetic chemistry.

Key words

natural product synthesis - cascade reaction - dibenzo[b,f]oxepines - anticancer agents - nucleophilic aromatic substitution - Knoevenagel condensation

Publikationsverlauf

Eingereicht: 04. Februar 2025

Angenommen nach Revision: 04. März 2025

Accepted Manuscript online:
04. März 2025

Artikel online veröffentlicht:
07. April 2025

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