Patent ID: 6921840

Claim:
A compound of Formula I: or a pharmaceutically acceptable salt thereof; wherein X is hydrogen, Cl, Br, I, NO 2 , or NR 3 R 4 ; Y is hydrogen, —CH 2 OR 5 , —CH 2 NCH 3 R 1 , NO 2 , or NR 3 R 4 ; Y′ is hydrogen, —CH 2 OR 5 , —CH 2 NCH 3 R 1 , NO 2 , or NR 3 R 4 ; provided that at least one of the Y or Y′ is —CH 2 NCH 3 R 1 ; Z is S, or O; A is hydrogen, Cl, I, or Br; R 1 is hydrogen, C 1 -C 5 alkyl, C 3 -C 8 cycloalkyl, C 1-5 alkylcarbonyl, (C 3 -C 8 cycloalkyl)carbonyl, phenyl, benzyl, naphthyl, or naphthylmethyl; R 2 is hydrogen or methyl; R 3 and R 4 are independently hydrogen, hydroxy, C 1 -C 5 alkyl, C 3 -C 8 cycloalkyl, C 1 - 5 alkylcarbonyl, (C 3 -C 8 cycloalkyl)carbonyl, phenyl, benzyl, naphthyl, or naphthylmethyl; R 5 is hydrogen, C 1 -C 5 alkyl, C 3 -C 8 cycloalkyl, C 1-5 alkylcarbonyl, (C 3 -C 8 cycloalkyl)carbonyl, phenyl, benzyl, naphthyl, or naphthylmethyl; R 6 is hydrogen, C 1 -C 5 alkyl, C 3 -C 8 cycloalkyl, C 1-5 alkylcarbonyl, (C 3 -C 8 cycloalkyl)carbonyl, phenyl, benzyl, naphthyl, or naphthylmethyl; and R 7 and R 8 are independently hydrogen, C 1 -C 5 alkyl or chloro; with the proviso that one or both of X or A is selected from the group consisting of 123 I, 131 I, 125 I, 77 Br and 76 Br.