Identification of Cherry and Hageman's "Compound XI" From Maize As Chelidonic Acid

Abstract

During examination of the nucleotide fraction of barley seedlings a compound that resembled an unidentified constituent of maize shoots-"compound XI" (Cherry and Hageman 1960; Cherry et al. 1961)-was found. The materials from barley and from maize have now been identified as chelidonic acid (4-oxopyran-2,6-dicarboxylic acid); this compound is present in a number of species of grasses (Table 1). In tissues and in extracts at pH values above 2 this strong acid exists mainly in an anionic form (cf. Miyamoto and Brochmann-Hanssen 1962) and is referred to below as chelidonate.