Fig. 1From: A convenient and efficient total solid-phase synthesis of DOTA-functionalized tumor-targeting peptides for PET imaging of cancerChemical structures of (left) cyclen (1,4,7,10-tetraazacyclododecane); (middle) DO3A (1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid); (right) DOTA (1,4,7,10-tetraazacyclododecane-N,N′,N′′,N′′′-tetraacetic acid)Back to article page