Exotines A and B, Two Heterodimers of Isopentenyl-Substituted Indole and Coumarin Derivatives from Murraya exotica

Exotines A and B (1 and 2), two heterodimers of isopentenyl-substituted indole and coumarin derivatives linked through a new fused heptacyclic ring system, were isolated from the roots of Murraya exotica. Their structures were established by comprehensive NMR and MS spectroscopic data analysis, and the absolute configurations were determined by single-crystal X-ray crystallographic analysis and ECD calculations. Compounds 1 and 2 showed inhibition of nitric oxide production in lipopolysaccharide-induced BV-2 microglial cells with IC50 values of 9.2 and 39.9 μM, respectively.