Abstract: Cyclic acetals and ketals play the important role in the synthetic chemistry of carbohydrates and widely utilized in specific protections for simultaneously two or more hydroxyl groups. In particular, alkylidene derivatives of monosaccharides are formed from interaction of these ones or their derivatives with aldehydes or ketones in the presence of acid as catalyst [1-5]. In all of alkylidene derivatives, the ethylidene ones of monosaccharides have received more attention than other particularly for the synthesis partially substituted sugars.