Many constituents of Taxus species have been known for many centuries to be highly toxic (1) and one in particular, taxolTM, has recently become the focus of great interest due to its use as an anticancer agent (2, 3, 4). As part of our taxane isolation programme, we have isolated two taxanes from the trunk bark of Taxus baccata L. (Taxaceae) and report herein their cytotoxicity against the P388 cell-line. The bark was collected from the grounds of the Christie Hospital, Manchester, England in June 1994 and a voucher specimen (SB01694) left in the Department of Chemistry, UMIST. The chloroform extract was shown to contain several compounds including the pseudoalkaloid 2'-deacetoxyaustrospicatine (1) (5—7) as the major component (ca. 50% w/w) and its cinnamoyl congener 2 (7). This is only the second report of the isolation of 1 and 2 from Taxus species; 1 has previously been found in the branches of Taxus cuspidata Sieb et Zucc (5, 6) and the leaves of Austrotaxus spicata Compton (Taxaceae) (7). Macerated bark (1 kg) was soaked in methanol (1.51) at room temperature for 1 week. The now red solution was decanted, filtered, and concentrated to 20% volume. This methanol solution was diluted (11 water) and extracted with chloroform (2 x 600 ml). The chloroform extract was dried (Na2SO4) and evaporated in vacuo to yield a green amorphous powder (6.43g). Repeated chromatography of this extract [neutral alumina (100 g), CH2C12: MeOH (97: 3, v/v)]; [neutral alumina (100 g), CH2CI2: MeOH (99: 1, v/v)] gave the taxine I derivative I (3.12g, 0.31%) and the taxicin derivative 2 (50mg, 0.005 %). The structures were determined by 1H- and 13C-NMR (including COSY and DEPT), mass, and IR spectroscopy and microanalysis (full details of the isolation and copies of the original spectra can be obtained from the author of correspondance). The spectroscopic data for both 1 and 2 are identical to that published (5, 6, 7). Larger quantities of the cinnamate 2 were obtained by Hoffman elimination of I by sequential treatment with iodomethane and potassium carbonate, a process previously reported for similar taxine derivatives (8), in 75 % overall yield. We report that both compounds show moderate cytotoxic activity against the P388 murine leukaemia cell line. The in vitro toxicity, as determined by MTT assay (9), is 13.3pg/ ml (IC50) for I and 15.2 pg/ml (IC50) for 2.