Dhurrin-6'-glucoside, a cyanogenic diglucoside from Sorghum bicolor

A novel cyanogenic diglucoside has been isolated from methanolic extracts of young seedlings of Sorghum bicolor. Its structure was established as dhurrin-6-glucoside from NMR, mass spectrometry and enzymatic hydrolysis data. Compared with dhurrin, which is the major cyanogenic glucoside in sorghum leaves, dhurrin-6-glucoside occurs only in low concentrations. In contrast, however, the diglucoside is present in significant amounts in guttation droplets of young Sorghum seedlings. The presence of the diglucoside and its occurrence in apoplasmic exudates supports the hypothesis that diglucosides represent metabolites of cyanogenic monoglucosides which can be translocated within the plant.