CONJUGATES OF RGD PEPTIDES AND PORPHYRIN OR (BACTERIO)CHLOROPHYLL PHOTOSYNTHESIZERS AND THEIR USES

• US 20120294801A1
• Filed: 04/16/2012
• Published: 11/22/2012
• Est. Priority Date: 08/23/2006
• Status: Active Grant

• Current Assignee: Yeda Research and Development Co. Ltd. (Weizmann Institute of Science)
• Original Assignee: Yeda Research and Development Co. Ltd. (Weizmann Institute of Science)
• Inventors: Scherz, Avigdor, Salomon, Yoram, Brandis, Alexander, Eren, Doron, Rubinstein, Efrat, Neimann, Karin
• Granted Patent: US 9,957,293 B2
• Time in Patent Office: Days
• US Class Current: 424/1.69
• CPC Class Codes: A61K 41/00 Medicinal preparations obtained by treating materials with wave energy or particle radiation ; Therapies using these preparations
• CPC Class Codes: A61K 41/0071 PDT with porphyrins having exactly 20 ring atoms, i.e. based on the non-expanded tetrapyrrolic ring system, e.g. bacteriochlorin, chlorin-e6, or phthalocyanines
• CPC Class Codes: A61K 47/64 Drug-peptide, drug-protein or drug-polyamino acid conjugates, i.e. the modifying agent being a peptide, protein or polyamino acid which is covalently bonded or complexed to a therapeutically active agent peptidic linkers A61K47/65
• CPC Class Codes: A61K 49/0036 Porphyrins used in photodynamic therapy A61K41/0071 or A61K41/0076; used as targeting group or modifying agent for targeting a therapeutic compound A61K47/546
• CPC Class Codes: A61K 51/082 the peptide being a RGD-containing peptide
• CPC Class Codes: A61K 51/088 conjugates with carriers being peptides, polyamino acids or proteins antibodies A61K51/10
• CPC Class Codes: A61P 35/00 Antineoplastic agents
• CPC Class Codes: A61P 35/04 specific for metastasis
• CPC Class Codes: C07K 5/0817 the first amino acid being Arg
• CPC Class Codes: C07K 5/10 Tetrapeptides
• CPC Class Codes: C07K 5/123 Tripeptides
• CPC Class Codes: C07K 5/126 Tetrapeptides
• CPC Class Codes: C07K 7/06 having 5 to 11 amino acids
• CPC Class Codes: C07K 7/64 Cyclic peptides containing only normal peptide links
• CPC Class Codes: G01N 2333/96411 Serine endopeptidases (3.4.21)
• CPC Class Codes: G01N 33/57426 leukemia

Abstract

Conjugates of porphyrin, chlorophyll and bacteriochlorophyll photosensitizers with RGD-containing peptides or RGD peptidomimetics are provided that are useful for photodynamic therapy (PDT), particularly vascular-targeted PDT (VTP), of tumors and nonneoplastic vascular diseases such as age-related macular degeneration, and for diagnosis of tumors by different techniques.

Claims

1. A conjugate of at least one RGD-containing peptide or RGD-peptidomimetic and a water soluble photosensitizer selected from a metalated porphyrin, a chlorophyll or a bacteriochlorophyll.

2. The conjugate according to claim 1, wherein the photosensitizer is a water-soluble tetraarylporphyrin of the formula:

3. The conjugate according to claim 2, wherein:

(i) the carbocyclic aryl radical by itself or as part of the mixed carboaryl-heteroaryl radical is a substituted or unsubstituted monocyclic or bicyclic aromatic radical selected from the group consisting of phenyl, biphenyl and naphthyl, and said heteroaryl radical by itself or as part of a mixed carboaryl-heteroaryl radical is a substituted or unsubstituted 5-6 membered aromatic ring containing 1-3 heteroatoms selected from the group consisting of O, S and N, said heteroaryl radical being selected from the group consisting of furyl, thienyl, pyrrolyl, imidazolyl, thiazolyl, pyridyl, pyrimidyl, and triazinyl;

(ii) any of the C₁-C₂₅ hydrocarbyl groups is a C₁-C₂₅ alkyl, alkenyl or alkynyl;

(iii) said negatively charged group is selected from the group consisting of COO⁻

, COS⁻

, SO₃⁻

, and PO₃²

(iv) said acidic group that is converted to a negatively charged group at the physiological pH is selected from the group consisting of COOH, COSH, SO₃H, and PO₃H₂, or a salt thereof;

(v) said positively charged group is;

(a) a cation derived from a N-containing group selected from the group consisting of —

N′

(RR′

R″

), —

(R)N—

N′

(RR′

R″

), O←

N⁺(RR′

)—

, >

C═

N⁺(RR′

), —

C(═

NR)—

NR″ and

—

(R)N—

C(═

NR)—

N⁺RR′

R″

, preferably an —

N⁺(RR′

R″

) group;

(b) a cation derived from a heteroaromatic compound containing one or more N atoms and optionally O or S atoms, selected from ther group consisting of pyrazolium, imidazolium, oxazolium, thiazolium, pyridinium, quinolinium, isoquinolinium, pyrimidinium, 1,2,4-triazinium, 1,3,5-triazinium and purinium, said cation being an end group or a group located within an alkyl chain;

or (c) an onium group selected from the group consisting of —

O⁺(RR′

), —

S⁺(RR′

), —

Se⁺(RR′

), —

Te⁺(RR′

), —

P⁺(RR′

R″

), —

As⁺(RR′

R″

), —

Sb⁺(RR′

R″

), and —

Bi⁺(RR′

R″

);

(vi) said basic group that is converted to a positively charged group under physiological conditions is selected from the group consisting of —

NRR′

, —

C(═

NR)—

NR′

R″

, —

NR—

NR′

R″

, —

(R)N—

C(═

NR)—

NR′

R″

, O←

NR—

, and >

C═

NR, or the basic group is a N-containing heteroaromatic radical selected from the group consisting of pyrazolyl, imidazolyl, oxazolyl, thiazolyl, pyridyl, quinolinyl, isoquinolinyl, pyrimidyl, 1,2,4-triazinyl, 1,3,5-triazinyl and purinyl, wherein said basic group is an end group or a group located within an alkyl chain;

wherein R, R′ and

R″

each independently is H, optionally substituted hydrocarbyl or heterocyclyl, or two of R, R′ and

R″

together with the N atom to which they are attached form a 3-7 membered saturated ring, optionally containing one or more heteroatoms selected from O, S or N, and optionally further substituted at the additional N atom, said 3-7 membered saturated ring being selected from the group consisting of aziridine, pyrrolidine, piperidine, morpholine, thiomorpholine, azepine and piperazine optionally substituted at the additional N atom by C₁-C₆ alkyl optionally substituted by halo, hydroxyl or amino.

4. The conjugate according to claim 3, wherein in the tetraarylporphyrin one to three of the carbocyclic aryl and/or heteroaryl radicals are substituted by one or more carboxy, C₁-C₈ alkylamino, amino-(C₁-C₈) alkylamino, hydroxy, or CONH₂ groups, and said chlorophyll or bacteriochlorophyll contains at least one group selected from the group consisting of a positively charged group, a negatively charged group, an acidic group that converts to a negatively charged group under physiological conditions and a basic group that converts to a positively charged group under physiological conditions.

5. The conjugate according to claim 2, wherein the photosensitizer is a water-soluble chlorophyll or bacteriochlorophyll of the formula I, II or III.

6. The conjugate according to claim 5, wherein the photosensitizer is selected from the group consisting of:

(i) a bacteriochlorophyll of the formula I, II or III, wherein M is 2H or a metal selected from the group consisting of Pd, Mn or Cu; and

(ii) a chlorophyll of the formula I, II or III, wherein M is 2H or a metal selected selected from the group consisting of Pd, Mn or Cu.

7. The conjugate according to claim 2, wherein the photosensitizer is a water-soluble tetraarylporphyrin.

8. The conjugate according to claim 6, wherein said tetraarylporphyrin is metalated with a metal atom selected from the group consisting of Cu, Mn, Ni and Gd.

9. The conjugate according to claim 2, wherein M is a radioisotope.

10. The conjugate according to claim 9, wherein M is ^99mTc, ⁶⁷Ga, ¹⁹⁵Pt, ¹¹¹In, ⁵¹Cr, ⁶⁰Co ¹⁰³Pd, ¹⁹⁵Pt, ¹⁰⁵Rh, ¹⁰⁶Rh, ¹⁸⁸Re, ¹⁷⁷Lu, ¹⁶⁴Er, ^117mSn, ¹⁵³Sm, ⁹⁰Y, ⁶⁴Cu, ⁶⁷Cu or ³²P.

11. The conjugate according to claim 5, wherein the photosensitizer is a bacteriochlorophyll of formula I or II, wherein R₄ at position 3 is acetyl, R₄ at position 8 is ethyl, and R′

₄ is methyl, or a chlorophyll of formula I or II, wherein R₄ at position 3 is vinyl, R₄ at position 8 is ethyl, and R′

₄ is methyl.

12. The conjugate according to claim 11, wherein the photosensitizer is selected from the group consisting of:

(i) a chlorophyll or bacteriochlorophyll of the formula II, wherein R₆ is —

NR₉R′

₉, R₉ is H and R′

₉ is C₁-C₁₀ alkyl substituted by (a) the acidic group SO₃H or an alkaline salt thereof;

(b) a basic group —

NH—

(CH₂)_2-6—

NRR′

wherein each of R and R′

independently is H, C₁-C₆ alkyl optionally substituted by NH₂, or R and R′

together with the N atom form a 5-6 membered saturated ring, optionally containing an O or N atom and optionally further substituted at the additional N atom by —

(CH₂)_2-6—

NH₂;

(c) one or more OH;

or (d) a polydentate ligand selected from the group consisting of EDTA, DTPA and DOTA, and their chelating complexes with metals;

(ii) a chlorophyll or bacteriochlorophyll of formula II, wherein R₁ and R₆ together form a cyclic ring comprising an RGD peptide or RGD peptidomimetic; and

(iii) a chlorophyll or bacteriochlorophyll of formula III, wherein X is —

NR₇, R₇ is —

NRR′

, R is H and R′

is C₂-C₆ alkyl substituted by SO₃⁻

or an alkaline salt thereof.

13. The conjugate according to claim 12, wherein (i) R₆ is —

NH—

(CH₂)₂—

SO₃K, —

NH—

(CH₂)₃—

SO₃K, —

NH—

(CH₂)₃—

NH—

(CH₂)₃—

NH₂, —

NH—

(CH₂)_2-1-morpholino, —

NH—

(CH₂)₃-piperazino-(CH₂)₃—

NH₂, —

NH—

CH₂—

CH(OH)—

CH₂(OH), or —

NH—

(CH₂)₃—

NH-DTPA or its chelating complex with Gd;

(ii) R₁ and R₆ together form a cyclic ring comprising —

NH-RGD-CO—

NH—

(CH₂)₂—

NH—

or —

NH-RGD-CO—

NH—

(CH₂)₂-piperazino-(CH₂)₂—

NH—

;

or (iii) R₇ is —

NH—

(CH₂)₃—

SO₃K.

14. The conjugate according to claim 2, wherein the photosensitizer is selected from the group consisting of:

(a) a bacteriochlorophyll of the formula II wherein m is 0;

R₁ is NH—

P, wherein P is the residue of an RGD-containing peptide or RGD peptidomimetic linked directly to the NH—

or via a spacer;

R′

₂ is methoxy;

R₄ at position 3 is acetyl and at position 8 is ethyl;

R′

₄ is methyl; and

wherein

(i) M is Pd, Mn, Cu or 2H and R₆ is —

NH—

(CH₂)₂—

SO₃⁻

Me or —

NH—

(CH₂)₃—

SO₃⁻

Me wherein Me is Na or K′

;

(ii) M is Pd or 2H and R₆ is —

NH—

CH₂—

CH(OH)—

CH₂—

OH;

(iii) M is 2H and R₆ is —

NH—

(CH₂)₃—

NH—

(CH₂)₃—

NH₂;

(iv) M is 2H and R₆ is —

NH—

(CH₂)₂-morpholino;

or

(v) M is 2H and R₆ is —

NH—

(CH₂)₃-piperazino-(CH₂)₃—

NH₂;

(b) a bacteriochlorophyll of the formula III wherein M is Pd;

R₁ is NH—

P, wherein P is the residue of an RGD-containing peptide or RGD peptidomimetic linked directly to the NH—

or via a spacer;

R₄ at position 3 is acetyl and at position 8 is ethyl;

R′

₄ is methyl;

X is N—

R₇ and R₇ is —

NH—

(CH₂)₃—

SO₃⁻

Me⁺, wherein Me⁺ is Na⁺ or K⁺;

(c) a bacteriochlorophyll of the formula I wherein M is Mn or 2H;

R₁ is NH—

P, wherein P is the residue of an RGD-containing peptide or RGD peptidomimetic linked directly to the NH—

or via a spacer;

R₂ is H or OH;

R₃ is COOCH₃;

R₄ at position 3 is acetyl and at position 8 is ethyl;

R′

₄ is methyl; and

R₅ is O;

(d) a chlorophyll of the formula II wherein M is selected from the group consisting of Mn, Cu or 2H;

R₁ is NH—

P, wherein P is the residue of an RGD-containing peptide or RGD peptidomimetic linked directly to the NH—

or via a spacer;

R₄ at position 3 is vinyl and at position 8 is ethyl;

R′

₄ is methyl; and

R₆ is —

NH—

(CH₂)₂—

SO₃⁻

Me⁺, wherein Me⁺ is Na⁺ or K⁺; and

(e) a tetraarylporphyrin wherein the RGD-containing peptide or RGD peptidomimetic is linked to at least one aryl group of the porphyrin moiety via a —

CO—

NH—

group.

15. The conjugate according to claim 2, wherein said RGD-containing peptide is composed of 4, 5, 6, 7, 9 or 25 amino acid residues, which may be (a) natural amino acids selected from the group consisting of Ala, Arg, Asp, Cys, Gln, Glu, Gly, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Tyr, and Val;

(b) modified natural amino acids wherein the modification includes D-modification, N-alkylation of the peptide bond, acylation or alkylation of the amino terminal group or of the free amino group of Lys, esterification or amidation of the carboxy terminal group or of a free carboxy group of Asp or Glu, and esterification or etherification of the hydroxyl group of Ser or Tyr preferably D-modification or N-methylation or (c) non-natural amino acids selected from 4-aminobutyric acid (Abu), 2-aminoadipic acid, diaminopropionic (Dap) acid, hydroxylysine, homoserine, homovaline, homoleucine, norleucine (Nle), norvaline (Nva), ornithine (Orn), and naphthylalanine (NaI); and

wherein said RGD peptidomimetic is a non-peptidic compound comprising a guanidine and a carboxyl terminal groups spaced by a chain of 11 atoms, at least 5 of said atoms being carbon atoms, and said chain comprises one or more O, S or N atoms and may optionally be substituted by oxo, thioxo, halogen, amino, C₁-C₆ alkyl, hydroxyl, or carboxy or one or more atoms of said chain may form a 3-6 membered carbocyclic or heterocyclic ring.

16. The conjugate according to claim 15, wherein said RGD-containing peptide is a cyclic peptide selected from the group consisting of:

(i) the pentapeptide cycloRGDfK (SEQ ID NO;

1), wherein f indicates D-Phe;

(ii) the nonapeptide herein designated RGD-4C (SEQ ID NO;

2);

(iii) the tetrapeptide cycloRGDK (SEQ ID NO;

4);

(iv) the pentapeptide cycloRGDf-n(Me)K (SEQ ID NO;

7), wherein f indicates D-Phe; and

(v) the pentapeptide cycloRGDyK (SEQ ID NO;

8), wherein y indicates D-Tyr;

or a linear peptide selected from the group consisting of;

(i) the hexapeptide GRGDSP (SEQ ID NO;

3);

(ii) the heptapeptide GRGDSPK (SEQ ID NO;

5), and

(iii) the peptide of sequence (GRGDSP)₄K (SEQ ID NO;

6); and

said RGD-peptidomimetic comprises in the chain N atoms and is substituted by an oxo group, selected from the group consisting of H₂N—

C(═

NH)NH—

(CH₂)₅—

CO—

NH—

CH(CH₂)—

(CH₂)₂—

COOH and H₂N—

C(═

NH)NH—

(CH₂)₃—

CO-piperidine-CONH—

(CH₂)₂—

COOH.

17. The conjugate according to claim 16, wherein the photosensitizer is selected from the group consisting of:

(a) a bacteriochlorophyll of the formula II, wherein m is 0;

R′

₂ is methoxy;

R₄ at position 3 is acetyl and at position 8 is ethyl;

R′

₄ is methyl, and wherein;

(i) M is Pd, R₁ is NH—

P wherein P is the residue of an RGD-peptidomimetic and R₆ is —

NH—

(CH₂)₂—

SO₃K, herein designated conjugate 40 and conjugate 41;

(ii) M is Pd, and R₁ and R₆ together form a cyclic ring comprising —

NH-RGD-CO—

NH—

(CH₂)₂—

NH—

, herein designated Conjugate 37;

(iii) M is 2H, and R₁ and R₆ together form a cyclic ring comprising —

NH-RGD-CO—

NH—

(CH₂)₂—

NH—

, herein designated Conjugate 38;

(iv) M is Pd, and R₁ and R₆ together form a cyclic ring comprising —

NH-RGD-CO—

NH—

(CH₂)₂-piperazino-(CH₂)₂—

NH—

, herein designated Conjugate 39;

(v) M is Pd, R₁ is NH—

P wherein P is the residue of the RGD-containing peptide of SEQ ID NO;

2, and R₆ is —

NH—

(CH₂)₂—

SO₃K, herein designated Conjugate 11;

(vi) M is 2H, R₁ is NH—

P wherein P is the residue of the RGD-containing peptide of SEQ ID NO;

1, and R₆ is —

NH—

(CH₂)₂—

SO₃⁻

K⁺, herein designated Conjugate 13;

(vii) M is Mn, R₁ is NH—

P wherein P is the residue of the RGD-containing peptide of SEQ ID NO;

1, and R₆ is —

NH—

(CH₂)₂—

SO₃K, herein designated Conjugate 14;

(viii) M is Cu, R₁ is NH—

P wherein P is the residue of the RGD-containing peptide of SEQ ID NO;

1, and R₆ is —

NH—

(CH₂)₂—

SO₃K, herein designated Conjugate 15;

(ix) M is Pd, R₁ is NH—

P wherein P is the residue of the RGD-containing peptide of SEQ ID NO;

1, and R₆ is —

NH—

(CH₂)₂—

SO₃K, herein designated Conjugate 24;

(x) M is Pd, R₁ is NH—

P wherein P is the residue of the RGD-containing peptide of SEQ ID NO;

1 and R₆ is —

NH—

(CH₂)₃—

SO₃K, herein designated Conjugate 19;

(xi) M is 2H, R₁ is NH—

P wherein P is the residue of the RGD-containing peptide of SEQ ID NO;

3 and R₆ is —

NH—

(CH₂)₂—

SO₃K, herein designated Conjugate 26;

(xii) M is Pd, R₁ is NH—

P wherein P is the residue of the RGD-containing peptide of SEQ ID NO;

5 and R₆ is —

NH—

(CH₂)₂—

SO₃K, herein designated Conjugate 33;

(xiii) M is Pd, R₁ is NH—

P wherein P is the residue of the RGD-containing peptide of SEQ ID NO;

6 and R₆ is —

NH—

(CH₂)₂—

SO₃K, herein designated Conjugate 34;

(xiv) M is Pd, R₁ is NH—

P wherein P is the residue of the RGD-containing peptide of SEQ ID NO;

7 and R₆ is —

NH—

(CH₂)₂—

SO₃K, herein designated Conjugate 35;

(xv) M is Pd, R₁ is NH—

CH [(—

(CH₂)₂—

CO—

NH—

P]₂, wherein P is the residue of the RGD-containing peptide of SEQ ID NO;

8 and R₆ is —

NH—

(CH₂)₂—

SO₃K, herein designated Conjugate 36;

(xvi) M is Pd, R₁ is NH—

P, wherein P is the residue of the RGD-containing peptide of SEQ ID NO;

1 and R₆ is —

NH—

CH₂—

CH(OH)—

CH₂OH, herein designated 23;

or

(xvii) M is 2H, R₁ is NH—

P, wherein P is the residue of the RGD-containing peptide of SEQ ID NO;

1, and R₆ is —

NH—

(CH₂)₃—

NH—

CO-DTPA herein designated Conjugate 43, or its chelate complex with Gd herein designated Conjugate 44;

(b) a chlorophyll of the formula II, wherein R₁ is NH—

P;

R₄ at position 3 is vinyl and at position 8 is ethyl;

R′

₄ is methyl; and

wherein;

(i) M is 2H, P is the residue of the RGD-containing peptide of SEQ ID NO;

1, and R₆ is —

NH—

(CH₂)₂—

SO₃K, herein designated Conjugate 16;

(ii) M is Mn, P is the residue of the RGD-containing peptide of SEQ ID NO;

1 and R₆ is —

NH—

(CH₂)₂—

SO₃K, herein designated Conjugate 17;

or

(iii) M is Cu, P is the residue of the RGD-containing peptide of SEQ ID NO;

1 and R₆ is —

NH—

(CH₂)₂—

SO₃K, herein designated Conjugate 18; and

(c) a bacteriochlorophyll of the formula I, wherein R₂ is OH;

R₃ is COOCH₃;

R₄ at position 3 is acetyl and at position 8 is ethyl;

R′

₄ is methyl; and

R₅ is O, and wherein;

(i) M is Mn and R₁ is NH—

P wherein P is the residue of the RGD-containing peptide of SEQ ID NO;

1, herein designated Conjugate 12;

(ii) M is 2H and R₁ is NH—

P wherein P is the residue of the RGD-containing peptide of SEQ ID NO;

1, herein designated Conjugate 27;

or

(iii) M is 2H and R₁ is NH—

(CH₂)₂—

NH—

CO—

P, wherein P is the residue of the RGD-containing peptide of SEQ ID NO;

4, herein designated Conjugate 32; and

(d) a tetraarylporphyrin conjugated to a cyclic RGD-containing peptide of SEQ ID NO;

1, wherein;

(i) M is Cu and the conjugate is Copper(II) meso-5-(4-cycloRGDfK-benzamido)-10,15,20-tris(4-carboxy-phenyl)porphine herein designated conjugate 21;

or

(ii) M is Gd and the conjugate is Gadolinium(III)meso-5-(4-cycloRGDfK-benzamido)-10,15,20-tris(4-carboxyphenyl)porphine herein designated conjugate 22.

19. A pharmaceutical composition comprising a conjugate as defined in claim 2, and a pharmaceutically acceptable carrier.

20. The pharmaceutical composition according to claim 19, wherein the conjugate is selected from the group consisting of:

(a) a conjugate of a chlorophyll of formula II, selected from the group consisting of the conjugates 16, 17 and 18;

(b) a conjugate of a bacteriochlorophyll of formula I, selected from the group consisting of the conjugates 12, 27 and 32;

(c) a conjugate of a bacteriochlorophyll of formula III, which is conjugate 19;

(d) a conjugate of a bacteriochlorophyll of formula II, wherein;

(i) the photosensitizer is conjugated with the RGD-containing peptide cycloRGDfK of SEQ ID NO;

1, and the conjugate is selected from the group consisting of the conjugates 13, 15, 23, 28, 29, 30, 31, 43, and 44;

(ii) the photosensitizer is conjugated with an RGD peptide selected from the peptides of SEQ ID NO;

2 to 8, and the conjugate is selected from the group consisting of the conjugates 11, 26, 33, 34, 35, and 36;

or

(iii) the photosensitizer is conjugated with an RGD peptidomimetic, and the conjugate is selected from the group consisting of the conjugates 40 and 41.

21. The pharmaceutical composition according to claim 19, wherein the photosensitizer is bacteriochlorophyll II and the conjugate is 24.

22. A method for tumor diagnosis or visualization of organs, comprising:

(a) administering to a subject suspected of having a tumor a conjugate according to claim 2; and

(b) subjecting the patient to diagnosis or visualization of organs.

23. The method according to claim 22, for:

(i) tumor diagnosis by dynamic fluorescence imaging, which comprises;

(a) administering to a subject suspected of having a tumor a conjugate according to claim 2, wherein M is 2H or a metal selected from the group consisting of Cu, Pd Gd, Pt, Zn, Al, Eu, Er, and Yb and isotopes thereof; and

(b) irradiating the subject by standard procedures and measuring the fluorescence of the suspected area, wherein a higher fluorescence indicates tumor sites;

(ii) tumor diagnosis by radiodiagnostic technique, which comprises;

(a) administering to a subject suspected of having a tumor a conjugate according to claim 2, wherein M is a radioisotope selected from the group consisting of ⁶⁴Cu, ⁶⁷Cu, ^99mTc, ⁶⁷Ga, ²⁰¹_Tl, ¹⁹⁵Pt, ⁶⁰Co, ¹¹¹In and ⁵¹_{Cr; and}

(b) scanning the subject in an imaging scanner and measuring the radiation level of the suspected area, wherein an enhanced radiation indicates tumor sites;

or

(iii) molecular magnetic resonance imaging (MRI) method for tumor diagnosis comprising the steps of;

(a) subjecting a patient suspected of having a tumor to magnetic resonance imaging and generating an MR image of the target region of interest within the patient'"'"'s body;

(b) administering to said patient a conjugate according to claim 2, wherein M is a paramagnetic metal selected from the group consisting of Mn³⁺, Cu²⁺, Fe³⁺, Eu³⁺, Gd³⁺ and Dy³⁺;

(c) irradiating the target region of interest within the patient'"'"'s body with the appropriate sensitizing radiation;

(d) generating at least one MR image of the target region of interest during and/or after irradiation; and

(e) processing and analyzing the data to diagnose the presence or absence of a tumor.

24. The method according to claim 23, wherein the tumor diagnosis is by radiodiagnostic technique, wherein said imaging scanner is positron emission tomography (PET) and M is ⁶⁴Cu or ⁶⁷Cu, or single photon emission tomography (SPET) and M is a radioisotope selected from the group consisting of ^99mTc, ⁶⁷Ga, ¹⁹⁵Pt, ¹¹¹In, ⁵¹Cr and ⁶⁰Co;

and wherein said tumor is a primary tumor or a metastasis from melanoma, colon, breast, lung, prostate, brain or head and neck cancer.

25. A method for tumor therapy comprising administering to an individual in need a conjugate according to claim 2, said method being:

(i) tumor photodynamic therapy, which comprises;

(a) administering the conjugate to an individual in need, wherein, when the photosensitizer is a porphyrin, the M is other than Mn, Cu, Gd or Ni; and

(b) irradiating the locale of the tumor;

or

(ii) tumor radiotherapy, which comprises administering the conjugate to an individual in need, wherein M is a radioisotope selected from the group consisting of ¹⁰³Pd, ¹⁹⁵Pt, ¹⁰⁵Rh, ¹⁰⁶Rh, ¹⁸⁸Re, ¹⁷⁷Lu, ¹⁶⁴Er, ^117mSn, ¹⁵³Sm, ^π

Y, ⁶⁷Cu and ³²P.

26. the method according to claim 25, wherein said tumor is a primary tumor or a metastasis from melanoma, colon, breast, lung, prostate, brain or head and neck cancer.

18. A bacteriochlorophyll derivative of formula II: