D-PENTOFURANOSE-DERIVATE UND VERFAHREN ZU IHRER HERSTELLUNG

The present invention relates to D-pentofuranose derivatives represented by the following formulas (1) through (4): (wherein A represents a chlorobenzoyl group; R represents a hydrogen atom, an aliphatic lower acyl group, a substituted or unsubstituted benzoyl group; each of X and Y represents a lower alkyl group; Z represents an ethynyl group or tri-lower alkyl silylethynyl group; the sugar moiety in formula (1) represents xylose; and the sugar moiety of each of formulas (3) and (4) represents ribose). The present invention also relates to a process for preparing the compound (2) characterized by oxidizing the compound of formula (1) with a hypochlorite in the presence of a catalytic amount of 2,2,6,6-tetramethylpiperidinoxy compound. These compounds are useful as intermediates in the synthesis of 3'-C-substituted ribonucleoside derivatives having excellent antitumor activities.