Identfication of new naphthalenones from Juglans mandshurica and evalution of their anticancer activities.

Two new naphthalenone compounds were isolated from green walnut husks of Juglans mandshurica and their structures were identified as 4-butoxybutoxy-5,8-dihydroxy-3,4-dihydro-2H-naphthalen-1-one (1), 4-ethoxyethoxy-5,8-dihydroxy-3,4-dihydro-2H-naphthalen-1-one (2). Compounds 1 and 2 were named as Juglanstetralone A (1) and Juglanstetralone B (2). Compound 1 showed more significant anti-tumor activity than 2 against gastric cancer BGC-823 cells, wih the IC50 of 125.89 (g(mL(-1).