Geobarrettin D, a Rare Herbipoline-Containing 6-Bromoindole Alkaloid from <i>Geodia barretti</i>

Abstract

Geobarrettin D (1), a new bromoindole alkaloid, was isolated from the marine sponge Geodia barretti collected from Icelandic waters. Its structure was elucidated by 1D, and 2D NMR (including 1H-15N HSQC, 1H-15N HMBC spectra), as well as HRESIMS data. Geobarrettin D (1) is a new 6-bromoindole featuring an unusual purinium herbipoline moiety. Geobarrettin D (1) decreased secretion of the pro-inflammatory cytokine IL-12p40 by human monocyte derived dendritic cells, without affecting secretion of the anti-inflammatory cytokine IL-10. Thus, compound 1 shows anti-inflammatory activity.

Keywords

• 6-bromoindole
• herbipoline
• <i>Geodia barretti</i>
• anti-inflammatory activity
• dendritic cells