Structure of sepedonin, a tropolone metabolite of <i>Sepedomum</i><i>chrysospermum</i> Fries

Abstract

The structures of sepedonin, 3,6,9-trihydroxy-3-methyl-1,3,4,7-tetrahydrocyclohepta[c]pyran-7-one, and its two dimethyl ether derivatives, as well as anhydrosepedonin and its three dimethyl ether derivatives, are unequivocally established from proton magnetic resonance and nuclear Overhauser enhancement parameters.