Complexation of Amino Acids by Cyclotetrachromotropylene in Aqueous Solution - Importance of CH-? and ?-? Interactions

Article abstract of DOI:10.1016/S0040-4020(01)87025-3

The stability constants K of the 1:1 host to guest complexes formed between the cyclic tetramer, cyclotetrachromotropylene, and amino acids in water at pD 7.0 and 25 deg C were determined by 1H nmr spectroscopy.The results indicate that the interactions between the aromatic ?-bonds of the host and the C-H bonds (for aliphatic amino acids) and aromatic ?-bonds (for aromatic amino acids) of the guests are the major factors responsible for the complexation.There is a linear relationship between log K and the number of C-H bonds interacting with the hydrophobic host cavity.