Crystal structure of two natural polyprenylated benzophenones from the Brazilian Cerrado, including a new natural product

The elucidation of the complex structure of a new benzophenone named goianone (1) was achieved through single-crystal X-ray diffraction, 1H and 13C NMR and ESI(+)-MS/MS data. Crystal structure of the known propolone A (2) was also determined for the first time here. Both compounds were isolated from floral resin and fruits extracts of Clusia rosea harvested in the Brazilian Cerrado. Compound 1 has a substituted homo-adamantyl ketone core with two seven-membered cycles and an additional spirofused seven-membered ring containing a peroxide bond. Its crystal structure represents the first crystallographic report of its complex pentacyclic core as well as the first report of a crystal structure of a peroxide prenylated benzophenone. Its pentacyclic structure is formed with two six-membered rings and three seven-membered rings. To date, this is only the second crystal structure report for a molecule bearing the lavandulyl moiety.

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