Oxidation of N- β-alanyldopamine by insect cuticles and its role in cuticular sclerotization

Abstract

The oxidation products formed when various types of insect cuticle were incubated with N- β-alanyldopamine (NBAD) have been studied by means of reversed phase high performance liquid chromatography, and compared to the corresponding products obtained when N-acetyldopamine (NADA) was incubated with the cuticles. The results indicate that NBAD is oxidized to o-quinone and quinone methide derivatives. In contrast, NADA can be oxidized by some cuticles not only to o-quinone and quinone methide derivatives, but it can also be desaturated to α, β-dehydro- N-acetyldopamine, a probable intermediate in β-sclerotization. Some implications for in vivo sclerotization are discussed.