"The rind of partially ripe fruits yields a
polyhydroxy-xanthone derivative termed
mangosteen, also ß-mangostin. That of fully
ripe fruits contains the xanthones, gartanin,
8-disoxygartanin, and normangosteen. A
derivative of mangosteen, mangosteen-e,
6-di-O-glucoside, is a central nervous system
depressant and causes a rise in blood pressure."
http://www.hort.purdue.edu/newcrop/morton/mangosteen.htmlit's a MAO (monoamine oxidase) depressant