Nomenclature of xyloglucan oligosaccharides

The following code letters are used for describing concisely the sequence of side-chains and unbranched glucose residues along the (1→4)-β-D-glucan backbone of xyloglucan. Oligosaccharides are named by listing these building blocks in sequence from non-reducing to reducing end. All residues are pyranose except arabinose which may be pyranose (Arap) or furanose (Araf). Square brackets indicate branching. For example, in ‘C’ an α-Xyl residue is linked to the 6-position of the Glc* and an α-Ara-(1→3)-β-Xyl group is linked to the 2-position of the same Glc*; thus ‘C’ could be represented as α-Xyl1→β-Glc*←β-Xyl←α-Ara. Likewise, in ‘N’ an Arap residue is linked to the 2-position of the Xyl and a β-Gal-(1→6)-β-Gal group is linked to the 4-position of the same Xyl.

(from: Franková and Fry. Trans-α-xylosidase, a widespread enzyme activity in plants, introduces (1→4)-α-D-xylobiose side-chains into xyloglucan structures. Phytochemistry 78: 29–43, 2012)