It has previously been reported that many Cyperus species are rich sources of naturally occurring quinones. Three flavanone quinones (remerin, breverin, scaberin) have been isolated and their sources and some properties are shown in Table 1. The structure of remerin was elucidated via acetylation, catalytic hydrogenation, UV, NMR, mass spectrometry, and synthesis from hesperetin. The n.m.r. spectrum of scaberin showed the replacement of the two E-coupled protons of remerin by a 6 proton methyl singlet, and breverin was similarly analyzed for its structure. To our knowledge, remerin and its homologues represent the first examples of unmodified flavanoid quinones found in nature.