Studies on cytotoxic constituents in pericarps of Mallotus japonicus, Part II

Two new phloroglucinol derivatives, mallotolerin (8) and mallotochromanol (9), were isolated from the cytotoxic fraction of the pericarps of Mallotus japonicus. The new derivatives were identified as 3-(3-methyl-2-hydroxybut-3-enyl)-5-(3-acetyl-2,4-dihydroxy-5-me thy l-6- methoxybenxyl)-phlorbutyrophenone (8) and 8-acetyl-5,7-dihydroxy-6-(3-acetyl-2,4-dihydroxy-5-methyl-6- methoxybenxyl)2,2-dimethyl-3-hydroxychroman (9) by their respective chemical and spectral data. These compounds were found to be cytotoxic against KB and L-5178Y cell lines in culture and to be moderately effective in inhibiting the growth of Ehrlich carcinoma in mice. Cytotoxic activities of the isolated phloroglucinol derivatives (1-9) from the pericarps are also discussed.