2'-o-modified rna

A method of manufacturing a ribonucleoside, a ribonucleotide, or a derivative thereof represented by the following Formula (I) and having a protective group at the 2′-position, the method comprising:

• a process of reacting a compound represented by the following Formula (III) with a compound represented by the following Formula (II).
• (In Formula (I), O* represents an oxygen atom of a hydroxyl group at the 2′ position of the ribonucleoside, the ribonucleotide, or the derivative thereof,
• R1 and R2 may be identical or different, and each represents a hydrogen atom, a C1-3 alkyl group, a C2-3 alkenyl group, a C2-3 alkynyl group, a hydroxy C2-3 alkyl group, or a C1-3 haloalkyl group,
• R3 and R4 may be identical or different, and each represents a hydrogen atom, a halogen atom, a C1-3 alkyl group, a C2-3 alkenyl group, a C2-3 alkynyl group, a hydroxy C2-3 alkyl group, or a C1-3 haloalkyl group,
• R5 and R6 may be identical or different, and each represents a hydrogen atom, a halogen atom, a C1-3 alkyl group, a C2-3 alkenyl group, a C2-3 alkynyl group, a hydroxy C2-3 alkyl group, a C1-3 haloalkyl group, a C1-3 alkyl group substituted with one or two C6-12 aryl groups, or a C6-12 aryl group optionally having a substituent, and
• R7 represents a halogen atom or a C1-3 haloalkyl group.)
• (In Formula (II), B represents a nucleic acid base that may be protected with a protective group, R21, R22, R23 and R24 may be identical or different, and each represents a C1-5 alkyl group, a C1-5 alkoxy group or a C1-5 haloalkyl group that may be straight or branched, and R1 and R2 represent the same as R1 and R2 in Formula (I).)
• (In Formula (III), R3 to R7 represent the same as R3 to R7 in Formula (I).)