A compound represented by the following formula: wherein: R 1 represents a hydroxyl-protecting group; R 2 represents a hydroxyl-protecting group; or R 1 and R 2 may together form an optionally substituted C 1-3 alkylene group; R 3C represents a hydrogen atom, an optionally substituted C 1-6 alkyl group, a halogen atom or a group represented by -OR 3a wherein R 3a represents a hydroxyl-protecting group; R 3D represents a hydrogen atom, an optionally substituted C 1-6 alkyl group, a halogen atom or a group represented by -OR 3a wherein R 3a represents a hydroxyl-protecting group; R 4 represents a halogen atom, a hydroxyl group, an optionally substituted C 1-6 alkylsulfonyloxy group or an optionally substituted arylsulfonyloxy group; R 5 and R 6 together represent =O or =N-OR 7, wherein R 7 represents a hydrogen atom, an optionally substituted C 1-6 alkyl group, an optionally substituted aryl group, an optionally substituted heterocyclic group or an optionally substituted silyl group; or R 4 and R 5 together represent a sulfur atom, and R 6 represents a hydroxyl group, provided that, when R 5 and R 6 together represent =O, then one of R 3C and R 3D is a halogen atom and the other is a hydrogen atom, and R 4 represents a halogen atom, an optionally substituted C 1-6 alkylsulfonyloxy group or an optionally substituted arylsulfonyloxy group; when R 4 and R 5 together represent a sulfur atom and one of R 3C and R 3D represents a hydrogen atom, then the other represents a halogen atom or an optionally substituted C 1-6 alkyl group when R 5 and R 6 together represent =N-OR 7, one of R 3C and R 3D represents -OR 3a and the other is a hydrogen atom, and R 4 represents an iodine atom, a hydroxyl group, an optionally substituted C 1-6 alkylsulfonyloxy group or an optionally substituted arylsulfonyloxy group, then R 1 and R 2 both represent an optionally substituted acyl group; and when R 5 and R 6 together represent =N-OR 7, both R 3C and R 3D represent hydrogen atoms, and R 4 represents a hydroxyl group, then R 1 and R 2 both represent an optionally substituted aroyl group. R 1 represents a hydroxyl-protecting group; R 2 represents a hydroxyl-protecting group; or R 1 and R 2 may together form an optionally substituted C 1-3 alkylene group; R 3C represents a hydrogen atom, an optionally substituted C 1-6 alkyl group, a halogen atom or a group represented by -OR 3a wherein R 3a represents a hydroxyl-protecting group; R 3D represents a hydrogen atom, an optionally substituted C 1-6 alkyl group, a halogen atom or a group represented by -OR 3a wherein R 3a represents a hydroxyl-protecting group; R 4 represents a halogen atom, a hydroxyl group, an optionally substituted C 1-6 alkylsulfonyloxy group or an optionally substituted arylsulfonyloxy group; R 5 and R 6 together represent =O or =N-OR 7, wherein R 7 represents a hydrogen atom, an optionally substituted C 1-6 alkyl group, an optionally substituted aryl group, an optionally substituted heterocyclic group or an optionally substituted silyl group; or R 4 and R 5 together represent a sulfur atom, and R 6 represents a hydroxyl group, provided that, when R 5 and R 6 together represent =O, then one of R 3C and R 3D is a halogen atom and the other is a hydrogen atom, and R 4 represents a halogen atom, an optionally substituted C 1-6 alkylsulfonyloxy group or an optionally substituted arylsulfonyloxy group; when R 4 and R 5 together represent a sulfur atom and one of R 3C and R 3D represents a hydrogen atom, then the other represents a halogen atom or an optionally substituted C 1-6 alkyl group when R 5 and R 6 together represent =N-OR 7, one of R 3C and R 3D represents -OR 3a and the other is a hydrogen atom, and R 4 represents an iodine atom, a hydroxyl group, an optionally substituted C 1-6 alkylsulfonyloxy group or an optionally substituted arylsulfonyloxy group, then R 1 and R 2 both represent an optionally substituted acyl group; and when R 5 and R 6 together represent =N-OR 7, both R 3C and R 3D represent hydrogen atoms, and R 4 represents a hydroxyl group, then R 1 and R 2 both represent an optionally substituted aroyl group.