@article{oai:nagoya.repo.nii.ac.jp:00023847,
 author = {Hara, Takashi and Kodama, Tetsuya and Takegaki, Yumi and Morihiro, Kunihiko and Ito, Ramon　Kosuke and Obika, Satoshi},
 issue = {1},
 journal = {Journal of Organic Chemistry},
 month = {Dec},
 note = {Conformationally restricted nucleoside analogues 2′,4′-BNA/LNA-7-deazaguanine (LNA-7cG) and 2′,4′-BNA/LNA-8-aza-7-deazaguanine (LNA-8n7cG), which avoid extra hydrogen bond formation at the 7-position of the guanine nucleobase, were successfully synthesized and incorporated into oligonucleotides. While the LNA-7cG-containing oligonucleotides show high duplex-forming ability with complementary DNA and RNA similar to LNA-G, the LNA-8n7cG-containing oligonucleotide has lower binding affinity than that of natural 2′-deoxyguanosine. This disparity in thermostability is also observed in 7-deazaadenosine analogues (LNA-7cA, LNA-8n7cA). Thermodynamic parameters and computational chemistry revealed that an inappropriate glycosidic torsion angle χ of 2′,4′-BNA/LNA-8-aza-7-deazapurine analogues destabilizes duplex formation in contrast to 2′,4′-BNA/LNA-7-deazapurine analogues. This result indicates that the nucleobase rotation angle plays an important role in duplex binding affinity. In addition, LNA-7cG-modified oligonucleotide effectively suppresses aggregation even in a guanine-rich sequence.},
 pages = {25--36},
 title = {Synthesis and Properties of 7-Deazapurine- and 8-Aza-7-deazapurine-Locked Nucleic Acid Analogues: Effect of the Glycosidic Torsion Angle},
 volume = {82},
 year = {2016}
}