Two new quinones, 1-hydroxy-5-pentyl-anthraquinone (1) and 4-(5-hydroxy-1,4-dioxo-1,4-dihydro-naphthalen-2-ylamino)-butyric acid methyl ester (2), together with two known quinones, 5-hydroxy-2-(2-hydroxy-ethylamino)-(1,4) naphthoquinone (3) and juglone (4) were isolated from the roots of Juglans mandshurica (Juglandaceae). Their structures were elucidated on the basis of spectral data. Compound 3 was isolated from the Juglans genus for the first time. Compounds 1-4 exhibited significant cytotoxicity towards cultured MDA-MB231, HepG2 and SNU638 cells with IC50 values ranging from 4.46 to 88.47 μM.
Keywords: Cytotoxicity; Juglandaceae; Juglans mandshurica; Quinones.