Monofunctionalization of Calix[4]arene Tetracarboxylic Acid at the Upper Rim with Isothiocyanate Group: First Bifunctional Chelating Agent for Alpha-Emitter Ac-225 - Chen, Xiaoyuan; Chen, Xiaoyuan; Ji, Min; Fisher, Darrell R; Wai, Chien M (Synlett, 1999)