Studies on monovalent anaphylactogens: evidence for a minimal size of the carbohydrate auxiliary group

N-[6-(DNCP-amino)hexanoyl]-beta-D-glucopyranosylamine was synthesized and was found to be unable to elicit DNCP-specific passive cutaneous anaphylaxis in the guinea pig. This contrasts with the considerable anaphylactogenicity of N1,N5-bis[2-deoxy-beta-D-glucopyranos-2-yl]-N2-[N3-DNCP-beta -alanyl]glutaminamide which likewise carries a single DNCP haptenic group but a larger carbohydrate moiety, comprised of two glucopyranosylamine groups instead of one. It is concluded that monovalent anaphylactogens, carrying in addition to the haptenic part a carbohydrate auxiliary group, generally require carbohydrate moieties larger than a single monosaccharide unit in order to be effective. Metabolic glucuronic acid conjugation will, therefore, not transform an inactive monovalent hapten into an anaphylactogen when only one glucuronic acid residue is attached.