ABSTRACT

This chapter describes the systems of nomenclature used to define the structures of the apolar and 'backbone' portions of lipid molecules. It explores systems of nomenclature that are appropriate to describe either individual phospholipid molecular species or phospholipid fractions that are uniform in some structural features but heterogeneous in others. Almost all biologically occurring phospholipids are constructed from two combinations of apolar and 'backbone' moieties: a glycerol moiety substituted with one or two acyl or alkyl chains; or an N-acylated sphingoid base. While glycerol itself is a symmetrical molecule, its carbon-2 becomes a chiral center when the 1-and 3-positions are not symmetrically substituted. Glycerophospholipids with one or two alkyl or alkenyl chains are named in the formal system in a manner very similar to the corresponding diacyl phospholipids, with ether-linked hydrocarbon chains described as alkyl or alkenyl residues in place of acyl residues.