Synthesis and NMR Elucidation of Novel Octa-Amino Acid Resorcin[4]arenes Derivatives

The synthesis of nine novel protected amino acid cavitands is reported. All have four pendant n-undecyl chains and 'headgroups' connected by a two-carbon spacer at eight 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 octa-substituted cavitands have symmetrical C-2v conformation at room temperature. These compounds have potential synthetic ion channel applications.