Rapid structural diversification of pseudopterosins : sulfuric acid promoted dehydro-aromatization yielding 14,15-dihydro-elisabatin B

Herein, we report a one-pot, sulfuric acid promoted, dehydro-aromatization reaction to rapidly convert pseudopterosins into 14,15-dihydro-elisabatin B. We propose a mechanism invoking redox cycling between the substrate catechol and ortho-quinone moieties. We also provide full spectroscopic characterization of two novel 5,6-dihydro-1. H-phenalen-2(4. H)-one derivatives, which are minor products of the reaction. This work opens up a unique route to rapidly provide libraries of novel marine natural product derivatives for drug discovery.