[Studies on the diterpenoids on Teucrium quadrifarium Buch-Ham]

Six neo-clerodane diterpenoids were isolated from the acetone extract of Teucrium quadrifarium Buch-Ham (I, II, IV, V, VI and VII). Five of them (I, II, IV, V and VII) were identified as known compounds, teucvidin, 12-epi-teucvidin, teuflin, 19-acetyl-teuspinin and teucvidin, respectively. Compound VI was found to be a new neo-clerodane diterpene, named teuquadrin B. Its structure has been determined from the physical and spectral data.