New indolequinazoline alkaloids from the fruits of Tetradium ruticarpum

In this research, five new indolequinazoline alkaloids (1–5), along with six known indolequinazoline alkaloids (6–11) were obtained from the fruits of Tetradium ruticarpum. Their structures were elucidated through comprehensive spectroscopic data of 1D and 2D NMR, HRESIMS and ECD spectra. Additionally, all isolates were assayed for their SIRT1 inhibitory activities in vitro and compounds 2, 7, 10 and 11 exhibited activities with IC50 values ranged from 43.16 to 118.35 μM.