@article{oai:nagasaki-u.repo.nii.ac.jp:00002044,
 author = {Ueda, Atsushi and Oba, Makoto and Izumi, Yuki and Sueyoshi, Yasuhito and Doi, Mitsunobu and Demizu, Yosuke and Kurihara, Masaaki and Tanaka, Masakazu},
 issue = {39},
 journal = {Tetrahedron},
 month = {Sep},
 note = {The chiral deuterium- and 13C-isotope-labeled α-aminoisobutyric acids CD3-Aib and 13CH3-Aib were enantioselectively synthesized from L-Ala aldimine using simplified Maruoka chiral phase-transfer catalysts. Homo-chiral (S)-CD3-Aib homopeptides, up to decamers, were prepared. A (R)-CD3-Aib polymer and (S)-13CH3-Aib polymer were also prepared. Conformational studies on homopeptides using CD spectra and an X-ray crystallographic analysis revealed that the preferred conformations were 310-helical structures comprising equal amounts of right-handed (P) and left-handed (M) helical-screw structures. The α-carbon chiral centers induced by the D- or 13C-isotope substitution of Aib were incapable of controlling the helical-screw directions of their oligopeptides and short polymers., Tetrahedron, 72(39), pp.5864-5871; 2016},
 pages = {5864--5871},
 title = {Helical structures of homo-chiral isotope-labeled α-aminoisobutyric acid peptides},
 volume = {72},
 year = {2016}
}