Two chiral dimethacrylate and one chiral diacrylate monomer containing an azobenzene group were synthesized and dissolved in a commercial ferroelectric liquid crystal (FLC) host. With two of the monomers, thermally induced radical polymerization with the mixture exposed to linearly polarized irradiation results in a bulk alignment of FLC in the direction perpendicular to the polarization of irradiation light as a result of the photoinduced orientation of azobenzene groups related to the transcis isomerization. The monomer that is most effective for photoalignment of FLC displays a polymer network formed by strings of colloidal particles (∼250 nm in diameter), which exerts a commanding effect on the alignment of FLC as being able to reorient the FLC by changing the polarization direction of subsequent irradiation. The study suggests that the network of colloidal particles is isotropic and that the photoalignment of azobenzene moieties on the large surface of the network dictates the alignment of FLC.

Self-assembly of cyclic peptides is an attractive strategy for making hollow tubular structures. [1][2][3][4] Stacking of ring-shaped molecules of flat conformation can be stabilized by intermolecular hydrogen bonds formed between the amide groups. Cyclic peptides of rationally designed chemical structures can form nanotubes of different internal diameters and structures, which may find applications in biology and materials sciences. [2,5,6] Generally, the self-assembly process occurs in solution, is often triggered by a change in solubility of the peptide in organic solvents, and results in crystals organized by nanotubes. Herein, we report on the observation of selfassembled structures of a cyclic peptide in a nematic liquid crystal (LC). Hexagonal hollow tubes that have diameters in the order of micrometers and reaching several millimetres in length were observed. Strong experimental evidence suggests the occurrence of a hierarchical and self-similar-structured self-assembly of the cyclic peptide. That is, individual molecules of hexagonal conformation stack up into hexagonal nanotubes, which then self-organize into larger aggregates with the same appearance. Each molecule provides both intra-and intertube H bonding that ensure the molecular stacking within and the packing of nanotubes. To the best of our knowledge, this is the first work exploring the use of liquid crystals for the self-assembly of cyclic peptides, and the results show the surprising impact of the liquid crystalline medium.Previous work showed that the lipophilic macrolactam cyclo-(NHCH 2 CH=CHCH 2 CO) 3 (E olefin) is soluble in ethanol and can be crystallized by diffusion of diethyl ether.[4] The crystal structure determined by X-ray crystallography shows the stacking of macrocycles, which have a

Self-assembly of cyclic peptides is an attractive strategy for making hollow tubular structures. [1][2][3][4] Stacking of ring-shaped molecules of flat conformation can be stabilized by intermolecular hydrogen bonds formed between the amide groups. Cyclic peptides of rationally designed chemical structures can form nanotubes of different internal diameters and structures, which may find applications in biology and materials sciences. [2,5,6] Generally, the self-assembly process occurs in solution, is often triggered by a change in solubility of the peptide in organic solvents, and results in crystals organized by nanotubes. Herein, we report on the observation of selfassembled structures of a cyclic peptide in a nematic liquid crystal (LC). Hexagonal hollow tubes that have diameters in the order of micrometers and reaching several millimetres in length were observed. Strong experimental evidence suggests the occurrence of a hierarchical and self-similar-structured self-assembly of the cyclic peptide. That is, individual molecules of hexagonal conformation stack up into hexagonal nanotubes, which then self-organize into larger aggregates with the same appearance. Each molecule provides both intra-and intertube H bonding that ensure the molecular stacking within and the packing of nanotubes. To the best of our knowledge, this is the first work exploring the use of liquid crystals for the self-assembly of cyclic peptides, and the results show the surprising impact of the liquid crystalline medium.Previous work showed that the lipophilic macrolactam cyclo-(NHCH 2 CH=CHCH 2 CO) 3 (E olefin) is soluble in ethanol and can be crystallized by diffusion of diethyl ether.[4] The crystal structure determined by X-ray crystallography shows the stacking of macrocycles, which have a

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