Ordered nanostructures from self-assembly of rod–coil oligomers with n-shaped rod and dendritic poly(ethylene oxide) coil segment

<div><p>The n-shaped rod–coil molecules consisting of an anthracene unit and two biphenyl groups connected by acetylenyl bonds as a conjugated rod segment and dendritic poly(ethylene oxide)s with different cross-sectional areas were synthesised. These new molecular structures were characterised by using ¹H NMR and MALDI-TOF-MS. The self-assembly of these molecules in the bulk state and in aqueous solution was investigated using differential scanning calorimetry, X-ray diffraction and transmission electron microscopy (TEM). In the bulk state, molecule <b>1a</b> with a linear coil segment, self-organised into lamellar crystalline structures, whereas molecules <b>1b</b> and <b>1c</b> with di- and tetra-branched dendritic wedges did not solidify at room temperature. Dynamic light scattering and TEM experiments reveal that in aqueous solution, the molecules exhibit a strong tendency to organise into the thread-like fibres along the axial direction of cylindrical micelles or into the wide fibroid bundles via the aggregation of cylindrical micelles as the cross-sectional area of the dendritic coil segments increases.</p></div

Construction of Various Supramolecular Assemblies from Rod–Coil Molecules Containing Biphenyl and Anthracene Groups Driven by Donor–Acceptor Interactions

Rod–coil amphiphilic functional molecules, comprising a rigid aromatic building block and hydrophilic oligoether dendrons as the coil segments, were synthesized. These compounds exhibit a powerful self-organizing ability to form supramolecular nanoparticles and long nanofibers in tetrahydrofuran/water solution, by controlling the intermolecular interaction of the rigid blocks. These molecules are able to form supramolecular polymers and, subsequently, to form sheetlike nanoaggregates, through charge-transfer interactions by the addition of a guest molecule, tetracyanoquinodimethane. Notably, upon addition of water-soluble 2,4,6-trinitrophenol, the self-assembly of these molecules exhibits the antagonistic effect owing to donor–acceptor and hydrophobic–hydrophilic interactions among the molecules. The experimental results reveal that various morphologies of rod–coil molecular assemblies can be obtained by tuning the molecular interaction and the hydrophilicity of guest electron-acceptor molecules. Interestingly, the cross-coupling reaction between phenylboronic acid and chlorobenzene occurs within the charge complexes of these molecular aggregates. This occurs in the nanoenvironment that affords an extremely concentrated reaction zone and reduces the activation energy barrier required for the cross-coupling reaction

Additional file 1: of Polymorphism rs189037CÂ >Â T in the promoter region of the ATM gene may associate with reduced risk of T2DM in older adults in China: a case control study

The raw data used in this paper. (XLS 50 kb

Relationship between number of wasp stings and clinical presentation/outcome.

<p>Relationship between number of wasp stings and clinical presentation/outcome.</p

Comparison of clinical features of venom-specific IgE(+) and venom-specific IgE(−) patients.

*<p>None of sIgE(+) or sIgE(−) patients present with this clinical feature.</p

Laboratory data of patients.

<p>Laboratory data of patients.</p

Clinical characteristics of wasp sting patients.

<p>¹ <18 years of age.</p><p>²≥18 years of age.</p