Collect. Czech. Chem. Commun. 1991, 56, 2298-2305

On equilibration of quassin and 4-epiquassin

Nada Stojanac and Zdenek Valenta

Department of Chemistry, University of New Brunswick, Bag Service 45222, Fredericton, New Brunswick, Canada E3B 6E2


Equilibration of quassin and 4-epiquassin is described. Various quassin derivatives are characterized and their relationship to quassin (I) is discussed. A regioselective deprotonation is achieved in quassin and 4-epiquassin (III) by the introduction of a diosphenolate grouping which makes a potentially acidic H-atom unavailable for attack by base.