Biphenyltetrols and Dibenzofuranones from Oxidative Coupling of Resorcinols with 4‐Alkylpyrocatechols: New Ciues to the Mechanism of Insect Cuticle Sclerotization

Abstract

Abstract Oxidation of 4‐alkylpyrocatechols 2 by means of an insect diphenoloxidase (laccase) or K 3 [Fe(CN) 6 ] yields, in the presence of resorcinols 1 (R 2  H), complex mixtures of products from which biphenyltetrols 3 (R 3  H) and dibenzofuranones 5 and 6 were isolated. It is suggested that similar homo‐coupling products are formed from pyrocatechols 2b and 2c in insects during cuticle sclerotization.