Amadori rearrangement is also called glucosamine rearrangement reaction. It is the process of obtaining 1- amino-1 deoxy -2 ketose from a molecule of glucosamine in the mixed solution of hydrochloric acid and pyridine.

Glucosamine opens the ring under the action of acid, and one position becomes enamine and the fifth position becomes hydroxyl. Tautomerism, where the 1.2 position is tautomeric to enol. Then interconvert, 2 is to become ketone. The hydroxyl group at the fifth position attacks the ketocarbonyl group and closes the ring to obtain fructosamine.