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Self-assembly of cyclic peptides is an attractive strategy for making hollow tubular structures.[1–4] 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-(NHCH2CH= CHCH2CO) 3(E olefin) is soluble in ethanol and can be crystallized by diffusion of diethyl …