Conformational mobility/instability

The conformational instability of DPM is partially transmitted to derivatives that are important in supramo-lecular chemistry, such as cavitands. " " Resorcarenes are conformationally mobile, with a AG for the rotation... 

Highly specific parameters that depend largely on conformer stability, such as refractive index and chromatographic behavior (mobility), will be more directly related to the magnitude of instability present in any single form. 

The reversed-phase HPLC method is a traditional method for the analysis of peptides and proteins. A good choice for the stationary phase could be a short-alkyl reversed-phase (e.g., C4) with wide pores (30 nm). It has been shown that large pore supports give distorted peaks with small collagens and triple helical peptides, resulting in poor resolution. The formation of broad peaks has been ascribed to conformational instability of the separated solutes and slow cis-trans isomerization of the peptide bonds. The best sorbents of those examined were diphenyl or non-porous Cig reversed-phases standard water-acetonitrile gradients were recommended as mobile phases. 

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