Sarothralin G is an antibacterial compound isolated from Hypericum japonicum Thunb. (Japanese spurfle). The structure of Sarothralin G contains phenolic and aromatic acid moieties and shows excellent antibacterial activity against Gram-positive bacteria such as Staphylococcus aureus, Bacillus subtilis and Nocardia spp., which is stronger than Sarothralen A, B and Saroaspidin A, B, C. Sarothralin G exhibits significant antibacterial potential.