Unguinol is a depsidone originally isolated from A. unguis. It is an inhibitor of pyruvate phosphate dikinase (PPDK; IC50 = 42.3 μM). It inhibits the growth of plants utilizing C4, but not C3, carbon fixation. Unguinol also inhibits the growth of the bacteria S. aureus and V. harveyi (GI50s = 8.7 and 69.5 μM, respectively) and H460, MCF-7, and SF-268 cancer cells (GI50s = 28.2, 50.8, and 44.3 μM, respectively).