<b>Sigmoiside E: A new antibacterial triterpenoid saponin from <i>Erythrina sigmoidea</i> (Hua)</b>

Abstract

Chemical analysis of the stem bark of Erythrina sigmoidea (Leguminoseae) yielded two known isoflavones, 6,8-diprenylgenisteine (3) and warangalone (4) as well as a new triterpenoid saponin designated sigmoiside E (1). Its structure was established by chemical and spectroscopic means as 16-O-β-D-galactopyranosyl maniladiol (1). Sigmoiside E exhibited antibacterial activity against gram-negative bacteria.

Keywords

• <i>Erythrina sigmoidea</i>
• Stem bark
• Triterpenoid
• Saponin
• Isoflavone
• Leguminoseae