Bisindole Alkaloids with Neural Anti-inflammatory Activity from <i>Gelsemium elegans</i>

Abstract

Three new trace bisindole alkaloids geleganimines A and B (<b>1</b>, <b>2</b>) and geleganamide (<b>3</b>) were isolated from the aerial parts of <i>Gelsemium elegans</i>. Their structures were elucidated by spectroscopy, particularly from their carbon–proton coupling constants, and electronic circular dichroism. Compounds <b>1</b>–<b>3</b> are the first bisindole alkaloids discovered from the genus <i>Gelsemium.</i> Geleganimine B exhibited anti-inflammatory activity indirectly by suppressing lipopolysaccharide-induced pro-inflammatory factors in BV2 microglial cells with an IC₅₀ value of 10.2 μM. These findings confirm the importance of bioactive trace components in medicinal plant research