Design, synthesis, and biological activity of novel triazole amino acids used to probe binding interactions between ligand and neutral amino acid transport protein SN1

Novel triazole amino acids were synthesized as probes to investigate ligand–protein binding interactions of the neutral amino acid transporter SN1. The bonding hypothesis to be tested was that the side chains of endogenous substrates are acting as H-bond acceptors. Although limited inhibition of 3H-l-glutamine uptake by SN1 expressing oocytes was observed, the synthetic compounds show a trend that suggests a hydrogen bond interaction just outside the endogenous ligand binding pocket.