Chloropupukeananin, the first chlorinated pupukeanane derivative, and its precursors from Pestalotiopsis fici

Chloropupukeananin (1), the first pupukeanane chloride with highly functionalized tricyclo-[4.3.1.0(3,7)]-decane skeleton and its possible biosynthetic precursors iso-A82775C (2) and pestheic acid (3), have been isolated from the plant endophyte Pestalotiopsis fici. The structure of 1 was determined by NMR spectroscopy and X-ray crystallography. Biogenetically, 1 could be derived from the Diels-Alder adduct of 2 and 3.