Bicyclic thiazolidine lactam peptidomimetics of the dopamine receptor modulating peptide Pro-Leu-Gly-NH2.

Bicyclic thiazolidine lactam peptidomimetics 3-5 have been synthesized as potential analogues of the dopamine receptor modulating peptide Pro-Leu-Gly-NH2 (PLG). Peptidomimetics 3 and 4 were designed to constrain two, psi 2 and phi 3, of the four torsion angles that define a beta-turn to values approximating those found for a type-II beta-turn, while 5 was designed as a compound that could not achieve a beta-turn conformation. Peptidomimetics 3 …