New peptides

1 . A targetable therapeutically active and/or diagnostic agent of formula (III)

V-L-Z  (III)

wherein the vector V is a peptide comprising the amino acid sequence of formula (I)

Z 1 -Arg-X 2 -X 3 -Ile-X 5 -X 6 -X 7 -X 8 -X 9 -Z 2 -Y 1   (I)

or formula (II)

Z 1 -Arg-Val(Arg/Lys)Ile-Asp-Gly-X 7 -Pro-X 9 -Z 2 -Y 1   (II)

wherein

X 2 is an amino acid selected from the group Val, Leu, Ile and Tyr

X 3 is an amino acid selected from the group Arg, Lys, Ile and Asn

X 5 is an amino acid selected from the group A sp and Asn

X 6 is an amino acid selected from the group Gly, Asn and Gln

X 7 is an amino acid selected from the group Ala, Met, Gln, Arg, Glu and Val,

X 8 is an amino acid selected from the group Pro, Gly, Ser and Arg

X 9 is an amino acid selected from the group Ala, Met, Gln, Arg, Gly and Val

Z 1 represent an amino acid residue capable of forming a disulphide bond, preferably a cysteine or a homocysteine residue, or a residue capable of forming a thioether preferably the residue is Q-C(═O) wherein Q represents —(CH 2 )n or —(CH 2 ) n —C 6 H 4 where n represents a positive integer 1 to 10 or is absent and

Z 2 represent an amino acid residue capable of forming a disulphide bond, preferably a cysteine or a homocysteine residue or is absent

Y 1 represents 1-10 amino acids or is absent

L represents a bond, a spacer or a linker and

Z represents an antineoplastic agent, a reporter or a group that optionally can carry an imaging moiety M.

2 . A targetable therapeutically active and/or diagnostic agent according to claim 1 wherein the vector V is a peptide comprising the amino acid sequence

Cys-Arg-Val-Arg-Ile-Asp-Gly-Ala-Pro-

(SEQ ID NO 1)

Ala-Cys,,

Cys-Arg-Val-Arg-Ile-Asp-Asn-Met-Pro-

(SEQ ID NO 2)

Met-Cys,,

Cys-Arg-Val-Arg-Ile-Asn-Gly-Gln-Pro-

(SEQ ID NO 3)

Gln-Cys,,

Cys-Arg-Val-Lys-Ile-Asp-Gly-Arg-Pro-

(SEQ ID NO 4)

Met-Cys,,

Cys-Arg-Leu-Lys-Ile-Asp-Gly-Met-Pro-

(SEQ ID NO 5)

Arg-Cys,,

Cys-Arg-Ile-Lys-Ile-Asp-Gly-Glu-Gly-

(SEQ ID NO 6)

Gln-Cys,,

Cys-Arg-Val-Tyr-Ile-Asp-Gly-Val-Ser-

(SEQ ID NO 7)

Val-Cys,,

Cys-Arg-Val-Ile-Ile-Asp-Gly-Arg-Arg-

(SEQ ID NO 8)

Met-Cys,,

Cys-Arg-Tyr-Asn-Ile-Asp-Gly-Arg-Pro-

(SEQ ID NO 9)

Gln-Cys,

or

Cys-Arg-Ile-Arg-Ile-Asp-Gln-Arg-Pro-

(SEQ ID NO 10)

Ala-Cys,.

3 . An agent according to claim 1 where Z is a chelating agent of formula IV

where:

each R 1 , R 2 , R 3 and R 4 is independently an R group;

each R group is independently H or C 1-10 alkyl, C 3-10 alkylaryl, C 2-10 alkoxyalkyl, C 1-10 hydroxyalkyl, C 1-10 alkylamine, C 1-10 fluoroalkyl, or 2 or more R groups, together with the atoms to which they are attached form a carbocyclic, heterocyclic, saturated or unsaturated ring.

4 . An agent as claimed in claim 1 wherein Z comprises a reporter moiety M wherein the reporter moiety comprises metal radionuclides, paramagnetic metal ions, fluorescent metal ions, heavy metal ions or cluster ions.

5 . An agent as claimed in claim 4 wherein the reporter moiety M comprises 90 Y, 99m Tc, 111 In, 47 Sc, 67 Ga, 51 Cr, 177m Sn, 67 Cu, 167 Tm, 97 Ru, 188 Re, 177 Lu, 199 Au, 203 Pb, 141 Ce or 18 F.

6 . An agent as claimed in claim 1 where each reporter (Z) can carry a multiplicity of vectors V.

7 . An agent as claimed in claim 1 where the antineoplastic agent, Z represent cyclophosphamide, chloroambucil, busulphan, methotrexate, cytarabine, fluorouracil, vinblastine, paclitaxel, doxorubicin, daunorubicin, etoposide, teniposide, cisplatin, amsacrine or docetaxel.

8 . A peptide comprising the amino acid sequence of formula (II)

Z 1 -Arg-Val(Arg/Lys)Ile-Asp-Gly-X 7 -Pro-X 9 -Z 2 -Y 1 (II)

wherein

X 7 is an amino acid selected from the group Ala, Met, Gln, Arg, Glu and Val,

X 9 is an amino acid selected from the group Ala, Met, Gln, Arg, Gly and Val

Z 1 represent an amino acid residue capable of forming a disulphide bond, preferably a cysteine or a homocysteine residue, or a residue capable of forming a thioether preferably the residue is Q-C(═O) wherein Q represents —(CH 2 )n or —(CH 2 ) n —C 6 H 4 where n represents a positive integer 1 to 10 or is absent and

Z 2 represent an amino acid residue capable of forming a disulphide bond, preferably a cysteine or a homocysteine residue or is absent

Y 1 represents 1-10 amino acids or is absent

or pharmaceutically acceptable salts thereof.

9 . A peptide comprising the amino acid sequence

Cys-Arg-Val-Arg-Ile-Asp-Gly-Ala-Pro-

(SEQ ID NO 1)

Ala-Cys,,

Cys-Arg-Val-Arg-Ile-Asp-Asn-Met-Pro-

(SEQ ID NO 2)

Met-Cys,,

Cys-Arg-Val-Arg-Ile-Asn-Gly-Gln-Pro-

(SEQ ID NO 3)

Gln-Cys,,

Cys-Arg-Val-Lys-Ile-Asp-Gly-Arg-Pro-

(SEQ ID NO 4)

Met-Cys,,

Cys-Arg-Leu-Lys-Ile-Asp-Gly-Met-Pro-

(SEQ ID NO 5)

Arg-Cys,,

Cys-Arg-Ile-Lys-Ile-Asp-Gly-Glu-Gly-

(SEQ ID NO 6)

Gln-Cys,,

Cys-Arg-Val-Tyr-Ile-Asp-Gly-Val-Ser-

(SEQ ID NO 7)

Val-Cys,,

Cys-Arg-Val-Ile-Ile-Asp-Gly-Arg-Arg-

(SEQ ID NO 8)

Met-Cys,,

Cys-Arg-Tyr-Asn-Ile-Asp-Gly-Arg-Pro-

(SEQ ID NO 9)

Gln-Cys,

or

Cys-Arg-Ile-Arg-Ile-Asp-Gln-Arg-Pro-

(SEQ ID NO 10)

Ala-Cys,.

10 . A pharmaceutical composition comprising an effective amount of a compound of general Formula (III) or a salt thereof, together with one or more pharmaceutically acceptable adjuvants, excipients or diluents.

11 . A method of generating enhanced images of a human or animal body previously administered with a contrast agent composition comprising a compound as claimed in claim 1 , which method comprises generating an image of at least part of said body.