Blutaparon portulacoides (St. Hil.) Mears (= Philoxerus portulacoides St. Hil.) (Amaranthaceae) is a species occurring in the Brazilian coast in two botanical varieties. The chemical study of an ethanolic extract led to the isolation of spinacetin 3- O-robinobioside as well as an unique glycosylated pseudo-dimeric flavonoid identified as 8,8""-methylene bis(spinacetin 3- O-robinobioside) mainly by NMR analyses (1H, 1H- 1H COSY, 13C, HMQC, HMBC) and MALDI-TOF mass spectrometry.