Popis: |
The synthesis of seven novel protected amino acid cavitands is reported. All have four pendant n -undecyl chains and ‘headgroups’ connected by a two-carbon spacer at four positions on the aromatic rings. The amino acids employed are glycine, alanine, phenylalanine, leucine, proline, tryptophan, serine, glutamine and lysine. The structures of the compounds were elucidated using one- and two-dimensional NMR techniques, which verified that all tetra-substituted cavitands have symmetrical C 4 v conformation. This is the first example of a complete study for amino acid cavitand derivatives. |