Patent ID: 6872809

Claim:
A nucleoside derivative represented by the general formula (1): wherein X is(are) the same or different and each represents an optionally substituted pyrimidine nucleic acid base or an optionally substituted purine nucleic acid base, Y and Y′ are the same or different and each represents at least one amino acid or amino acid derivative selected from the group consisting of serine, threonine, ornithine, aspartic acid, glutamc acid, lysine, arginine, cysteine, methionine, δ-hydroxylysine, N-aminoethylglycine, N-aminoethylserine, N-aminoethyllysine, N-aminoethylornithine, N-aminoethylaspartic acid, N-aminoethylglutamic acid, homoglutamic acid, β-thiocarbonylaspartic acid, γ-thiocarbonylglutamic acid, and δ-thiocarbonyihomoglutamic acid, R 1 represents a hydrogen atom or a hydroxyl group, A represents a carbonyl or thiocarbonyl group, 1 is an integer of 0 to 5, and n is an integer of 1 to 100.