A study of methods for the synthesis of urea and carbamate glycosides, starting with unprotective carbohydrates, led to the preparation of amino acid-carbohydrate conjugates in aqueous media.
The one step process, involving reactions between urea and protecting group free d-glucose, N-acetyl-d-glucosamine or d-xylose in acidic aqueous solution, furnishes the corresponding β-urea glycosides.