The floral resins of five species of Clusia belonging to two taxonomic sections of the genus wee investigated These resins are used by pollinating bees for nest construction. The major components of these resins are polyisoprenylated benzophenones, a class of biologically active compounds. We found clusianone and three hitherto unknown compounds, grandone, nemorosone and hydroxy-nemorosone. Copyright (C) 1996 Elsevier Science Ltd373664276430