Composition of Protocyanin, A Self‐Assembled Supramolecular Pigment from the Blue Cornflower, Centaurea cyanus

Abstract
Reconstruction, not decomposition, was used to determine the composition of the pigment from the blue petals of cornflowers, protocyanin. Comparison of optical and mass spectra of natural and reconstructed protocyanin revealed it to be a complex of an anthocyanin and a malonylflavone with iron(III) and magnesium ions.