Monoterpenoid indole alkaloids from the fruits of Gelsemium elegans and their anti-inflammatory activities
Two novel monoterpenoid indole alkaloids (MIAs), gelsechizines A-B (1–2), along with four known ones (3–6) were isolated from the fruits of Gelsemium elegans. Compound 1 features a new carbon skeleton with two additional carbon atoms forming a 4-methylpyridine unit. Their structures with absolute configurations were elucidated by NMR, MS, X-ray diffraction and electronic circular dichroism (ECD) calculations. Compounds 1–3 showed significant anti-inflammatory effects in vivo and in vitro, which may be related to the inhibition of the trecruitment of neutrophils and macrophages as well as the secretion of TNF-α and IL-6. Preliminary structure–activity relationship analysis revealed that the β-N-acrylate moiety plays an important role in the anti-inflammatory effect.
Alkaloids, macrophages, structure-activity,