Hyperjaponiol A (1) and B (2), two undescribed acylphloroglucinols were isolated from the aerial parts of Hypericum japonicum Thunb. ex Murray., as well as six known ones were identified as hyperipersion A (3), hyperipersion B (4), hyperipersion C (5), hyperbeanol B (6), hyperbeanol C (7) and tomoeone B (8), respectively. Their structures were determined by various methods including NMR, HR-ESI-MS, and quantum chemical calculations. Biologically, the anti-renal injury activity of all compounds was evaluated by MTT method. Among them, compounds 2 and 6 exhibited the strongest effect than other isolates, with an in vitro cell survival ratio of 92.74 ± 0.36% and 90.28 ± 0.75% at 10 μM, respectively.
Liu et al. (Sat,) studied this question.