Anti-staphylococcal activity of ent-kaurane-type diterpenoids from Croton tonkinensis

Ent-kaurane-type diterpenpoids 1-11, isolated from the dried leaves of the endemic Vietnamese medicinal plant Croton lonkinensis Gagnep. (Euphorbiaceae), were evaluated for inhibitory activity against Staphylococcus aureus and n-iethicillin-resistant S. altretts (MRSA) strains. The most active diterpenoids, 2, 3, and 8, exhibited minimum inhibitory concentrations (MICs) of 32, 500, and 125 mu g/ml, respectively, against MRSA strains.