Allevi, P., Anastasia, M., Ciuffreda, P., Fiecchi, A., & Scala, A. 1987 A simple transformation of carminic acid into kermesic acid.. Journal of Organic Chemistry 52: 5469-5472.

Notes: Carminic acid is the principal component of the food dye cochineal, obtained from the insect Dactylopius coccus. The aglycon moiety of carminic acid is represented by kermesic acid, the coloring matter of kermes, the most ancient dyestuff on record. The authors' interest in the study of the biological properties of kermesic acid prompted them to search for a simple transformation of the commercially available carminic acid into kermesic acid.