Antiangiogenic Tocotrienol Derivatives from <i>Garcinia amplexicaulis</i>

Abstract

Phytochemical investigation of a dichloromethane extract from <i>Garcinia amplexicaulis</i> stem bark led to the isolation of four new tocotrienols (<b>1</b>–<b>4</b>); two known tocotrienols, two triterpenes, and a xanthone were also isolated. Their structures were mainly established using NMR and MS methods. The main compounds isolated, δ-amplexichromanol (<b>1</b>) and γ-amplexichromanol (<b>2</b>), were evaluated on VEGF-induced angiogenesis using a Matrigel assay. Compounds <b>1</b> and <b>2</b> inhibited in vitro angiogenesis of VEGF-induced human primary endothelial cells in the low nanomolar range. Their capacity to inhibit VEGF-induced proliferation of endothelial cells partially explained this activity, although δ-amplexichromanol (<b>1</b>) also prevented adhesion and migration processes