Guanidine−Acylguanidine Bioisosteric Approach in the Design of Radioligands: Synthesis of a Tritium-Labeled<i>N</i><sup>G</sup>-Propionylargininamide ([<sup>3</sup>H]-UR-MK114) as a Highly Potent and Selective Neuropeptide Y Y<sub>1</sub>Receptor AntagonistMax Keller, Armin Buschauer, Christoph Hutzler et al.|Journal of Medicinal Chemistry|2008Cited by 48