ABSTRACT
A disaccharide, by definition, gives two monosaccharides on hydrolysis. It forms by the condensation of the anomeric hydroxyl group of one monosaccharide with the hydroxyl group of the second with the concomitant release of a water molecule. The bonds linking the two monosaccharide units are called the glycosidic bonds and the oxygen atom connecting the two is called the “bridge” or “glycosidic” oxygen atom. Several disaccharides can be derived from a single monosaccharide due to the possibility of a number of linkage types in contrast to amino acids and mononucleotides which can form only one type of dimer. For example, two d-glucopyranoses can form eleven different disaccharides. The conformational analyses of kojibiose, nigerose and maltose have been extended by using “flexible” pyranose rings during energy minimization. The potential energies were calculated using the MM3 force field for both the a and ß anomers and different orientations of the hydroxyl hydrogen atoms were also considered for each anomer.
