title: Folding Patterns in a Family of Oligoamide Foldamers.
abstract: A series of small, unsymmetrical pyridine-2,6-dicarboxylamide oligoamide foldamers with varying lengths and substituents at the end groups were synthetized to study their conformational properties and folding patterns. The @-type folding pattern resembled the oxyanion-hole motifs of enzymes, but several alternative folding patterns could also be characterized. Computational studies revealed several alternative conformers of nearly equal stability. These folding patterns differed from each other in their intramolecular hydrogen-bonding patterns and aryl-aryl interactions. In the solid state, the foldamers adopted either the globular @-type fold or the more extended S-type conformers, which were very similar to those foldamers obtained computationally. In some cases, the same foldamer molecule could even crystallize into two different folding patterns, thus confirming that the different folding patterns are very close in energy in spite of their completely different shapes. Finally, the best match for the observed NOE interactions in the liquid state was a conformation that matched the computationally characterized helix-type fold.
authors.affiliation: Department of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box 35, 40014 JYU (Finland), Fax: (+358) 14-260-2501.
authors.forename: Minna
authors.initials: M
authors.lastname: Kortelainen
authors.affiliation: Department of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box 35, 40014 JYU (Finland), Fax: (+358) 14-260-2501.
authors.forename: Aku
authors.initials: A
authors.lastname: Suhonen
authors.affiliation: Institute of Organic Chemistry, Research Center for Natural Sciences, Hungarian Academy of Sciences, Magyar Tudósok Körútja 2, 1117, Budapest (Hungary).
authors.forename: Andrea
authors.initials: A
authors.lastname: Hamza
authors.affiliation: Institute of Organic Chemistry, Research Center for Natural Sciences, Hungarian Academy of Sciences, Magyar Tudósok Körútja 2, 1117, Budapest (Hungary). papai.imre@ttk.mta.hu.
authors.forename: Imre
authors.initials: I
authors.lastname: Pápai
authors.affiliation: Department of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box 35, 40014 JYU (Finland), Fax: (+358) 14-260-2501.
authors.forename: Elisa
authors.initials: E
authors.lastname: Nauha
authors.affiliation: Department of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box 35, 40014 JYU (Finland), Fax: (+358) 14-260-2501.
authors.forename: Sanna
authors.initials: S
authors.lastname: Yliniemelä-Sipari
authors.affiliation: Department of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box 35, 40014 JYU (Finland), Fax: (+358) 14-260-2501. maija.nissinen@jyu.fi.
authors.forename: Maija
authors.initials: M
authors.lastname: Nissinen
authors.affiliation: Department of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box 35, 40014 JYU (Finland), Fax: (+358) 14-260-2501. petri.pihko@jyu.fi.
authors.forename: Petri M
authors.initials: PM
authors.lastname: Pihko
keywords: crystal growth; foldamers; hydrogen bonds; oligomerization; protein folding