Betacyanins from the bracts of Bougainvillea glabra were isolated and characterized by a combination of spectroscopic techniques (DAD-HPLC, NMR, LC-MS, GC-MS, electrospray MS, tandem MS) as gomphrenin I (betanidin 6-O-β-glucoside) and various derivatives of bougainvillein-v (betanidin 6-O-β-sophoroside), i.e. mono- and diglucosylsophorosides which are acylated with p-coumaric and caffeic acid (mono- and diesters). Besides the betacyanins, B. glabra bracts accumulated large amounts of flavonols (kaempferol and quercetin conjugates) reaching ratios of flavonol to betacyanin of 1: 1.