A phytochemical investigation on the stems and leaves of Damnacanthus hainanensis caused the isolation and characterisation of a new monoterpenoid indole alkaloid, damnahainanline (1), as well as seven known analogues (2-8). The molecular structure of 1 was determined in the light of comprehensive spectroscopic data analyses and the known analogues 2-8 were determined via comparing their experimental spectroscopic data with the reported spectroscopic data in the literature. The anti-inflammatory effects as well as anti-HIV activities of all isolates 1-8 in vitro were assessed. As a result, compounds 1-8 showed remarkable inhibitory effects against nitric oxide (NO) production induced by lipopolysaccharide in mouse macrophage RAW 264.7 cells holding an IC50 values in the range of 0.78 ± 0.06 to 10.89 ± 0.16 μM. At the same time, compounds 1-8 displayed remarkable anti-HIV-1 reverse transcriptase (RT) effects with EC50 values ranging from 0.31 to 7.27 µM.
Keywords: Damnacanthus hainanensis; anti-HIV-1 effects; anti-inflammatory activities; damnahainanline; monoterpenoid indole alkaloid.