Exiguaquinol: A Novel Pentacyclic hydroquinone from Neopetrosia exigua that inhibits Helicobacter pylori MurI

Abstract

Bioassay-guided fractionation of the methanol extract of the Australian sponge Neopetrosia exigua led to the isolation of exiguaquinol (2), a new pentacyclic hydroquinone that inhibited Helicobacter pylori glutamate racemase (MurI) with an IC50 of 4.4 卮 Its structure and relative configuration were assigned on the basis of spectroscopic data. Exiguaquinol (2), bearing a novel pentacyclic ring skeleton, is the first natural product to show inhibition of H. pylori MurI. Its protein-ligand modeling is also discussed.