Isopimarane diterpenoids from Aeollanthus rydingianus and their antimicrobial activity

The diterpenoids 19-acetoxy-7,15-isopimaradien-3β-ol (4) and 7,15-isopimaradien-19-ol (5), two of the six isopimaranes isolated from the plant, showed significant antimicrobial activity against Staphylococcus aureus and Enterococcus hirae.