Patent ID: 8822671

Claim:
A ribonucleoside, a ribonucleotide, or a derivative thereof having a protective group at the 2′-position, wherein the protective group is represented by the following Formula (I): wherein O* represents an oxygen atom of the hydroxyl group at the 2′ position of the ribonucleoside, the ribonucleotide, or the derivative thereof, R 1 and R 2 each represents a hydrogen atom, R 3 and R 4 may be identical or different, and each represents a hydrogen atom, a halogen atom, a C 1-3 alkyl group, a C 2-3 alkenyl group, a C 2-3 alkynyl group, a hydroxy C 2-3 alkyl group, or a C 1-3 haloalkyl group, R 5 and R 6 may be identical or different, and each represents a hydrogen atom, a halogen atom, a C 1-3 alkyl group, a C 2-3 alkenyl group, a C 2-3 alkynyl group, a hydroxy C 2-3 alkyl group, a C 1-3 haloalkyl group, a C 1-3 alkyl group substituted with one or two C 6-12 aryl groups, or a C 6-12 aryl group optionally having a substituent, and R 7 represents a halogen atom or a C 1-3 haloalkyl group, wherein the derivative thereof is the ribonucleoside or the ribonucleotide having a 2-cyanoethyldiisopropyl phosphoramidite protecting group at the 3′ position and/or a 4,4′-dimethoxytrityl group at the 5′ position, or having a 1,1,3,3-tetraisopropyldisiloxane-1,3diyl protecting group attached to both the 3′ position and the 5′ position to form a cyclic structure.