Patent ID: 8231858

Claim:
A diagnostic imaging agent: wherein: R 1 is selected from hydrogen, hydroxy, C 1-6 alkyl, C 6-14 aryl, C 7-20 arylalkyl, or together with R 5 and the carbon to which it is attached forms either a C 6-8 cycloalkyl ring or a C 4-6 heterocyclic ring, or together with R 4 forms a C 4-6 heterocyclic ring containing 5-7 atoms and 1 or 2 heteroatoms chosen from N or O; R 2 is a γ-emitting isotope of iodine attached via a direct covalent bond to the 3- or 4-position of the aromatic ring; R 3 is hydrogen; R 4 is C 6-14 aryl, C 4-6 heteroaryl, C 7-20 arylalkyl, C 7-20 carbamoylaryl or arylcarbamoylaryl; and, R 5 is selected from hydrogen or C 1-6 alkyl.