Diversity in the sialic acids

Abstract

Fig. 1. The sialic acids. The nine-carbon backbone common to all sialic acids is shown. Natural substitutions described to date (at C4, C5, C7 C8, and C9,) are indicated. Additional diversity is generated by various types of glycosidic linkage (at R3) by generation of lactones (at C1 ), by dehydro forms (eliminating R3), and anhydro forms © 1992 Oxford University Press.