Robust trans-Amide Helical Structure of Oligomers of Bicyclic Mimics of β-Proline: Impact of Positional Switching of Bridgehead Substituent on Amide cis-trans Equilibrium.
Wang, Siyuan; Otani, Yuko; Liu, Xin; Kawahata, Masatoshi; Yamaguchi, Kentaro; Ohwada, Tomohiko; The Journal of organic chemistry 79 (2014) 5287–5300; doi:10.1021/jo500916j

data_4029454
_publ_section_title
;
 Robust trans-Amide Helical Structure of Oligomers of Bicyclic Mimics of
 \b-Proline: Impact of Positional Switching of Bridgehead Substituent on
 Amide cis-trans Equilibrium.
;
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;
 Flack x determined using 1520 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons and Flack (2004), Acta Cryst. A60, s61).
;
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;
 w=1/[\s^2^(Fo^2^)+(0.0353P)^2^+0.3207P]
 where P=(Fo^2^+2Fc^2^)/3
;
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