An unusual taxodione derivative from hairy roots of Salvia austriaca

From a root culture of Salvia austriaca, transformed with Agrobacterium rhizogenes, a new diterpenoid was isolated and its chemical structure was determined as 7-(2-oxohexyl)-11-hydroxy-6, 12-dioxo-7,9(11),13- abietatriene [= 7-(2-oxohexyl)-taxodione] on the basis of spectroscopic methods, especially 1D and 2D NMR, and by comparison with structurally related compounds. This compound represents a hitherto unknown 2-oxohexyl diterpenoid derivative. Cytotoxic studies revealed that the new compound exhibited high cytotoxic activity against three cancer cell lines with IC50 values ranging from 0.63 to 0.72 mu M. Its cytotoxic effectiveness against the cancer cells was ten fold higher than that of taxodione. (C) 2012 Elsevier B.V. All rights reserved.