Patent ID: 8846885

Claim:
A compound comprising a protected base, which is represented by the formula (I): wherein q is any integer of not less than 0; Base 2 in the number of q+1 are each independently a nucleic acid base protected by a group having a C 5-30 straight chain or branched chain alkyl group and/or a C 5-30 straight chain or branched chain alkenyl group; P 1 is a hydrogen atom, or a temporary protecting group removable under acidic conditions; X is a hydrogen atom, an optionally protected hydroxyl group, a halogen atom or an organic group crosslinked with the 4-position carbon atom; X′ in the number of q are each independently a hydrogen atom, an optionally protected hydroxyl group, a halogen atom or an organic group crosslinked with the 4-position carbon atom; P 2 in the number of q+1 are each independently a protecting group removable under basic conditions; R 34 in the number of q are each independently an oxygen atom or a sulfur atom; and R e and R f are each independently a C 1-6 alkyl group, or a 5- or 6-membered saturated cyclic amino group formed together with the adjacent nitrogen atom.