Two amphiphilic water-soluble sulfonatomethylated calix[4]resorcinarene derivatives were studied by various 1 H NMR techniques ( 1 H NMR titration, 2D NOESY, NMR diffusion measurements). The derivative with methyl moieties at the lower rim (1) was found to be nonaggregated in the range 0 -10 mM in aqueous solutions. Lengthening of the lower rim substituent to pentyl (2) results in self-aggregation of 2 in aqueous solutions with the aggregation number varying from 3 at 1 mM to 20 at 10 mM. The 2D NOESY 1 H NMR spectroscopy data reveal an unusual head-to-tail packing mode in aqueous solutions, resulting from the cooperative effect of weak hydrophobic interactions. Binding of guests (tetramethylammonium and N-methylpyridinium) results in additional stabilization of the aggregates whilst the head-to-tail packing mode of the aggregate is retained.

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Water soluble hexanuclear molybdenum cluster assembled with triblock copolymer gives luminescent response on ion-pairing with difloxacin through energy transfer.

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Efficient hydrophilic stabilization of Gd(iii) complexes with Keplerate polyanions for high relaxivity, colloid stability and low cytotoxicity.