Photoresponsive nucleotide analog capable of photocrosslinking in visible light region

A compound represented by the following formula I:

• (I)
• in which formula I:
• R1 is a group selected from the group consisting of a hydrogen atom, a halogen atom, a methyl group, a fluorine-substituted methyl grow, an ethyl group, a fluorine-substituted ethyl group, and a C1-C3 alkylsulfanyl group;
• X is a group represented by the following formula Is or IIs:
• in which formula Is:
• R11 and R12 are each independently a group selected from the group consisting of a hydrogen atom, a C1-C3 alkyl group, and a C1-C3 alkoxy group;
• na is 1 or 2;
• R21 and R22 are each independently a group selected from the group consisting of a hydrogen atom, a C1-C3 alkyl group, and a C1-C3 alkoxy group;
• nb is 0 or 1;
• R31 and R32 are each independently a group selected from the group consisting of a hydrogen atom, a C1-C3 alkyl group, and a C1-C3 alkoxy group;
• nc is 0, 1, 2 or 3, and nc+nd is an integer of 0 to 3;
• R41 and R42 are each independently a group selected from the group consisting of a hydrogen atom, a C1-C3 alkyl group, and a C1-C3 alkoxy group;
• nd is 0, 1, 2 or 3, and nc+nd is an integer of 0 to 3;
• Q1 is a group selected from the group consisting of:
• a hydrogen atom:
• a phosphate group formed together with O bonded to Q1;
• a nucleotide, nucleic acid or peptide nucleic acid linked via a phosphodiester bond formed by a phosphate group formed together with O bonded to Q1;
• and
• a protecting group selected from:
• a trityl group, a monomethoxytrityl group, a dimethoxytrityl group, a trimethoxytrityl group, a trimethylsilyl group, a triethylsilyl group, a t-butyldimethylsilyl group, an acetyl group, and a benzoyl group;
• Q2 is a group selected from the group consisting of:
• a hydrogen atom;
• a phosphate group formed together with O bonded to Q2;
• a nucleotide, nucleic acid or peptide nucleic acid linked via a phosphodiester bond formed by a phosphate group formed together with O bonded to Q2;
• and
• a protecting group selected from:
• a 2-cyanoethyl-N,N-dialkyl(C1-C4)phosphoramidite group, a methylphosphonamidite group, an ethylphosphonamidite group, an oxazaphospholidine group, a thiophosphite group, a TEA salt of —PH(═O)OH, a DBU salt of —PH(═O)OH, a TEA salt of —PH(═S)OH, and a DBU salt of —PH(═S)OH;
• or
• in which formula Is:
• R51 and R52 are each independently a group selected from the group consisting of a hydrogen atom, a C1-C3 alkyl group, and a C1-C3 alkoxy group;
• ne is 1, 2 or 3;
• R61 and R62 are each independently a group selected from the group consisting of a hydrogen atom, a C1-C3 alkyl group, and a C1-C3 alkoxy group;
• nf is 0, 1, 2 or 3;
• Q1 is a groups selected from the group consisting of:
• a hydrogen atom;
• a phosphate group formed together with O bonded to Q1;
• a nucleotide, nucleic acid or peptide nucleic acid linked via a phosphodiester bond formed by a phosphate group formed together with O bonded to Q1;
• and
• a protecting group selected from:
• a trityl group, a monomethoxytrityl group, a dimethoxytrityl group, a trimethoxytrityl group, a trimethylsilyl group, a triethylsilyl group, a t-butyldimethylsilyl group, an acetyl group, and a benzoyl group;
• Q2 is group selected from the group consisting of:
• a hydrogen atom;
• a phosphate group formed together with O bonded to Q2;
• a nucleotide, nucleic acid or peptide nucleic acid linked via a phosphodiester bond formed by a phosphate group formed together with O bonded to Q2;
• and
• a protecting group selected from:
• a 2-cyanoethyl-N,N-dialkyl(C1-C4)phosphoramidite group, a methylphosphonamidite group, an ethylphosphonamidite group, an oxazaphospholidine group, a thiophosphite group, a TEA salt of —PH(═O)OH, a DBU salt of —PH(═O)OH, a TEA salt of —PH(═S)OH, and a DBU salt of —PH(═S)OH.