Synthesis of Phenyl‐1‐benzoxepinols Isolated from Butcher's Broom and Analogous Benzoxepines

Extracts of Ruscus aculeatus L., known as butcher's broom, are mainly used for the treatment of chronic venous insufficiency (CVI). In a recent study on the phenolic compounds of Rusci rhizoma, new phenyl-1-benzoxepinols were isolated. As the therapeutic effect of butcher's broom is ascribed to the pharmacological activity of the main constituents, steroidal saponins and their aglycones the ruscogenins, the role of the newly identified compounds was of interest. Owing to the low availability of the compounds by isolation, we synthesized them for pharmacological testing. In an ORAC–fluorescein assay they revealed a significant antioxidative activity, which may contribute to the anti-inflammatory properties of the phenolic fraction obtained from Rusci rhizoma extracts.

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