Inspired by the unique bending property of a cisplatin cross-linked DNA with high-mobility group box proteins (such as HMGB1), we designed and synthesized novel oligonucleotides (ODNs) containing a cyclic 2'-deoxyuridylate dimer which possesses an alkylene linkage as a "clasp" with various lengths. The newly synthesized ODNs were revealed to have the deep bending property with HMGB1 A-box protein binding ability. This strategy could provide ready access to systematic preparations of structurally altered ODNs, which would be a useful system for studying structure-specific DNA recognition. Of great significance is this single-point modification of DNA, which results in significant global alteration of the structural features of DNA to acquire new functions.