Structurally diverse monoterpenoid indole alkaloids from Damnacanthus hainanensis as well as their potential anti-inflammatory and anti-HIV effects

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.