Folates form a wide range of chemical compounds that all exhibit folic acid functions. All folates have three distinct, structurally different compounds: a pteridine nucleus, a para-aminobenzoic acid residue, and at least one molecule of glutamic acid (Illus. 1). The chemical name of the monoglutamate form is pteroylmonoglutamate. Polyglutamates are formed by peptide bond linkages of additional glutamic acid molecules.