Sekikaic acid is a phenolic lichen metabolite that has been found inH. obscurataand has diverse biological activities.^1,2,3It scavenges superoxide and DPPH radicals in cell-free assays when used at a concentration of 0.5 µM.¹Sekikaic acid is active against the rg recombinant strain of respiratory syncytial virus (RSV; IC₅₀= 5.69 µg/ml).²It inhibits the protein-protein interaction between mixed lineage leukemia 1 (MLL1) and the GACKIX domain of CREB-binding protein (CBP; IC₅₀= 34 µM).³

1.Thadhani, V.M., Choudhary, M.I., Ali, S., et al.Antioxidant activity of some lichen metabolitesNat. Prod. Res.25(19)1827-1837(2011) 2.Lai, D., Odimegwu, D.C., Esimone, C., et al.Phenolic compounds with in vitro activity against respiratory syncytial virus from the Nigerian lichen Ramalina farinaceaPlanta Med.79(15)1440-1446(2013) 3.Majmudar, C.Y., HØjfeldt, J.W., Arevang, C.J., et al.Sekikaic acid and lobaric acid target a dynamic interface of the coactivator CBP/p300Angew. Chem. Int. Ed. Engl.51(45)11258-11262(2012)