Trisaccharides are oligosaccharides (carbohydrate) composed of three monosaccharides with two glycosidic bonds connecting them. Oligosaccharides have diverse functions in biological systems, however, the structural determination of oligosaccharides remains difficult and has created a bottleneck in carbohydrate research. Similar to the disaccharides, each glycosidic bond can be formed between any hydroxyl group on the component monosaccharides [see: Wikipedia].