Anti-Complementary Constituents From Artemisia vestita Alleviate H1N1-Induced Acute Lung Injury.

Artemisia vestita is a traditional Tibetan folk medicine. Bioactivity-guided fractionation revealed that the petroleum ether fraction of A. vestita possessed potent anti-complementary activity (CH50: 0.016 ± 0.006 mg/mL), demonstrating therapeutic efficacy against H1N1-induced viral pneumonia in murine models. Subsequent phytochemical analysis of this bioactive extract using silica gel chromatography coupled with semi-preparative high-performance liquid chromatography yielded 14 compounds, including three new monoterpenes (1-3) and one coumarin (13) with relatively high abundance. Notably, studies on the activity of the isolated compounds revealed that the coumarin (scopoletin) exhibits dominant anti-complementary activity and provides significant protective effects against H1N1-induced viral pneumonia in mice. This study provides insights into the development and utilization of A. vestita and scopoletin.