Patent ID: 7666392

Claim:
A cyclopeptide of formula I: wherein: R 1 is selected from the group consisting of a side chain of a natural amino acid and a side chain of an unnatural amino acid, wherein the natural amino acid and the unnatural amino acid is either in the D or L form; R 2 and R 3 are each independently selected from the group consisting of H, C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, aryl, aryl-(C 1 -C 6 alkylene)-, a 3- to 7-membered carbocycle, and a 3- to 7-membered heterocycle, wherein the alkyl, alkenyl, alkynyl, aryl-alkylene, carbocycle and heterocycle groups are each optionally substituted; R 7 is absent or is selected from the group consisting of H, C 1 -C 6 alkyl, C 2 -C 6 alkenyl, C 2 -C 6 alkynyl, aryl, aryl-(C 1 -C 6 alkylene)-, a 3- to 7-membered carbocycle, and a 3- to 7-membered heterocycle, wherein the alkyl, alkenyl, alkynyl, aryl-alkylene, carbocycle and heterocycle groups are each optionally substituted; wherein R 2 , R 3 and R 7 are not all H; X is a 5 or 6-membered heterocycle or a linker comprising a hydrophilic moiety selected from the group consisting of hydroxyl, carbonyl, sulfonamide, sulfonate, phosphate, polar amino acid moiety, PEG moiety, sugar mimetic, and sugar moiety; Y is a 5 or 6-membered heterocycle, or a linker comprising a hydrophilic moiety selected from the group consisting of hydroxyl, carbonyl, sulfonamide, sulfonate, phosphate, polar amino acid moiety, PEG moiety, sugar mimetic, and sugar moiety; where at least one of X and Y, but not both X and Y is a 5 or 6-membered heterocycle; and w is 1, 2, 3, 4, or 5; wherein any one of X, Y, R 2 , R 3 , and R 7 comprises a radionuclide selected from the group consisting of positron or gamma emitters.