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Updated: Apr 11, 2026
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Glycosyl-Templated Chiral Helix Stapling of Ethynylpyridine Oligomers by Alkene Metathesis between Inter-Pitch Side
Hajime Abe1, Fumihiro Kayamori2, Masahiko Inouye2
1Graduate School of Pharmaceutical Sciences, University of Toyama, Sugitani 2630, Toyama 930-0194 (Japan), Fax: (+81) 76-434-5049. abeh@pha.u-toyama.ac.jp.
Abstract:
Ethynylpyridine polymers and oligomers consisting of 4-substituted pyridine rings linked by acetylene bonds at the 2- and 6-positions have been investigated. Ethynylpyridine oligomers covalently linked with a glycosyl chiral template form chiral helical complexes by intramolecular hydrogen bonding, in which the chirality of the template is translated to the helix. With a view to fixation of the chiral architecture, D/L-galactosyl- and D/L-mannosyl-linked ethynylpyridine oligomers have been developed with 4-(3-butenyloxy)pyridine units having alkene side chains. The helical structures are successfully stapled by alkene metathesis of the side chains. Subsequent removal of the chiral templates by acidolysis produces template-free stapled oligomers. The chiral, template-free, stapled oligomers show chiral helicity, which is resistant to polar solvents and heating.
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