Seco-cassine diterpenoids and cytotoxic activities of the constituents from the roots of Acacia farnesiana

Acacia farnesiana (L.) Willd (Leguminosae) is an erect pantropic shrub with forking prickles and widely distributed in the southern part of Taiwan [1]. The preliminary study showed the methanolic extract of its root owning selected cytotoxicity against the HSC-3 cancer cell line. The MeOH extract was partitioned into n-hexane, EtOAc, n-BuOH and H₂O-soluble layers. Investigation of the active n-hexane- and EtOAc-soluble fractions of A. farnesiana led to the isolation of six new diterpenoids, farnesiranes CI, CII, DI, DII, EI, and EII, together with 18 known compounds. Among these compounds, farnesirane CI in 30µM showed the cytotoxic activity against HSC-3 cell line. The structures of these compounds were determined through spectral data.

[1] Huang TC, Ohashi H. Leguminosae in Flora of Taiwan, 2nd edition, Vol. 2. Taipei: Editorial Committee of the Flora of Taiwan; 1993: 162 – 396