Helical foldamer

Sanford AR, Yamato K, Yang XW, Yuan LH, Han YH, Gong B. Well-defined secondary structures information-storing molecular duplexes and helical foldamers based on unnatural peptide backbones. Eur J Biochem 2004 271 1416-1425. 

Figure 10.83 Helical molecules (a) helical molecular and double helical crystal structure of the hydrogen bonded helix 10.132 (Copyright Wiley-VCH Verlag GmbH Co. KGaA. Reproduced by permission) and (b) helical foldamer comprising 3V3 turns based on a hydrazone derivative.96...

Other Backbone-Rigidified Helical Foldamers with Interior Cavities. 25... 

Except for the folding aromatic oligoamides developed by us, few other helical foldamers reported so far contain any meaningful interior cavities. Unnatural foldamers with interior cavities include those described by Lehn [29] and Moore [31]. A few examples of porous helical oligoamides have started to appear in recent years. 

Another recent article was published by Takata and co-workers. The polymer was composed of oligothiophene monomers (pink) as a planarity-switchable spacer and a C2-chiral spirobifluorene monomer (green). Under redox conditions, the polymer switched from a one-handed helical shape to a coil-shaped rigid helical foldamer (Figure 5.25). 

Although the field of double helical foldamers is yet to be fully explored, we believe that the creation of novel structures with unique and advanced functions such as circularly polarized luminescence and artificial transmembrane ion channels may stem from the double helical topology. As a result, the combinations of multiple chemical components present in the intertwined helices that form when two oligomers are instructed to self-assemble together provides a coherent platform on which supramolecular chemists will stand and lead an orchestra of secondary interactions. 

Chapter 9 Synergistic Effects in Double Helical Foldamers.149... 

Other sophisticated examples of moleciflar recognition were reported with helical foldamers [10-12]. Foldamers 8 spontaneously formed helical structures through intramolecular solvophobic interactions, in which some guests were nicely accommodated. Since the pyridine-containing foldamers 8b and... 

Another family of organic molecules that spontaneously form helical nanotubes are the long hydrogen bonding-driven aiyl-based foldamers [17-19]. The main considerations for the structural design of helical foldamers are the size of the monomers and the substitution pattern of the aromatic rings used. Indeed, once... 

By introducing hydrogen bonding from the interior and the exterior of the backbone, Li and co-workers prepared a helical foldamer from a tridecameric aromatic hydrazide (Fig. 8.4a) [23]. The presence of the three-centered hydrogen bonding helps to stabilize the helical conformation which forms a tubular structure composed of two turns (Fig. 8.4b, c). In this helical structure, half of the carbonyl... 

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