Prenylated benzophenones from Clusia sandiensis

Abstract From an extract of fruits of Clusia sandiensis the known clusiaphenone A and the new clusiaphenone B (2,4,6-trihydroxy-3,5-diisopentenylbenzophenone) were isolated. Moreover, the structure of machuone, a new polyisoprenylated modified benzophenone, has been determined on the basis of high field 2D NMR techniques. The keto-enolic equilibrium of clusianone, also isolated from the extract, was studied by examination of its 1 H and 13 C NMR spectra.