Two new 8-O-4'-type lignans from the stem of Schima superba and their cell growth inhibitory activities against human cancer cell lines.

Two new lignans (1 and 2) were isolated from the EtOH extracts of the stem of Schima superba, and elucidated as (7R,8S)-1-(3,4-dimethoxyphenyl)-2-O-(2-methoxy-4-omegahydroxypropylphenyl)propane-1,3-diol (1) and threo-1-(4-hydroxy-3-methoxyphenyl)-1-methoxy-2-{4-[1-formyl-(E)-vinyl]-2-methoxyphenoxy}-3-propanol (2) by spectral analysis. Compounds 1 and 2 showed cell growth inhibitory activity against HeLa, CNE, HepG-2, and HEp-2 cell lines. Compound 1 exhibited significant cytotoxicities with IC₅₀ values of less than 4 μg/ml against all the tested cell lines.