Self-assembly strategies for improving the water solubility of new amino acid calix[4]resorcinarenes

- We report the synthesis of amino acid calix[4]resorcinarenes.
- The water-soluble forms of the amino acid calix[4]resorcinarenes were obtained.
- In the alkaline solutions the amino acid calix[4]resorcinarenes form vesicles.
- At low pH the amino acid macrocycles are easily solubilized in anionic micelles.

C-methylcalix[4]resorcinarenes with glycine, d,l-alanine and d,l-valine residues and their water-soluble forms are obtained. The water solubility enhancements of these macrocycles depend on the structures of the amino acid residues; the solubility of macrocycles in aqueous solutions is enhanced by increasing basicity with branching amino acid residues. The controlled fabrication of specific nanostructures from the self-assembly of molecular building blocks through fine pH tuning by the use of sodium hydroxide and sodium n-dodecyl sulfate renders the calix[4]resorcinarenes studied more soluble in water.