Patent ID: 7922998

Claim:
A compound of the general formula: M-N—O—P-G wherein M is a metal chelator of formula 8: optionally complexed with a radionuclide, wherein R 1 is hydrogen, C 1 -C 20 alkyl optionally substituted with one or more carboxy groups, C 3 -C 10 cycloalkyl, C 4 -C 20 cycloalkylalkyl, aryl, arylalkyl or the two R 1 groups, taken together, form a straight or cyclic C 2 -C 10 alkylene group or an ortho-disubstituted arylene; R 2 is hydrogen, carboxy, or an optionally substituted group selected from C 1 -C 20 alkyl, C 3 -C 10 cycloalkyl, C 4 -C 20 cycloalkylalkyl, aryl, arylalkyl, a group bearing an acidic moiety, and a group bearing an amino moiety, each of which may be further optionally substituted with functional groups selected from carboxy and amino groups which allow conjugation with a suitable molecule able to interact with physiological systems via an amide bond; R 3 , R 4 and R 5 , which are the same or different, are hydrogen, carboxy, or an optionally substituted group selected from C 1 -C 20 alkyl, C 3 -C 10 cycloalkyl, C 4 -C 20 cycloalkylalkyl, aryl, arylalkyl, a group bearing an acidic moiety and a group bearing an amino moiety, each of which may be further optionally substituted with functional groups selected from carboxy and amino groups which allow conjugation with a suitable molecule able to interact with physiological systems via and amide bond; and FG, are the same or different, are carboxy, —PO 3 H 2 or —RP(O)OH groups, wherein R is hydrogen, or an optionally substituted group selected from C 1 -C 20 alkyl, C 3 -C 10 cycloalkyl, C 4 -C 20 cycloalkylalkyl, aryl, arylalkyl, a group bearing an acidic moiety and a group bearing an amino moiety, each of which may be further optionally substituted with functional groups selected from carboxy and amino groups which allow conjugation with a suitable molecule able to interact with physiological systems via an amide bond; wherein for the general formula only: N is absent, an alpha amino acid, a non-alpha amino acid with a cyclic group or other linking group; O is an alpha amino acid or a non-alpha amino acid with a cyclic group; P is absent, an alpha amino acid, a non-alpha amino acid with a cyclic group, or other linking group; and G is a GRP receptor targeting peptide, wherein at least one of N, O or P is a non-alpha amino acid with a cyclic group.