Five novel diarylheptanoids from green walnut husks (Juglans regia L.)

A ethanol extract of green walnut husks (Juglans regia L.) was isolated by various chromatographic techniques yielding 5 previously unknown diarylheptanoids, namely Juglanin F (1), Juglanin G (2), Juglanin H (3), Juglanin I (4) and Juglanin J (5), respectively, together with 12 known diarylheptanoids. The structures of these 17 compounds were elucidation on the basis of spectroscopic analysis. Upon evaluation of compounds 1–5 on the human hepatoma cells HepG2, compound 3 exhibited moderate inhibitory activity with IC50 27.72 μM. [Display omitted]