WO2008025941A2 - Composés pour imagerie et thérapie - Google Patents

Composés pour imagerie et thérapie Download PDF

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Publication number
WO2008025941A2
WO2008025941A2 PCT/GB2007/002950 GB2007002950W WO2008025941A2 WO 2008025941 A2 WO2008025941 A2 WO 2008025941A2 GB 2007002950 W GB2007002950 W GB 2007002950W WO 2008025941 A2 WO2008025941 A2 WO 2008025941A2
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alk
group
substituted
unsubstituted
ring
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PCT/GB2007/002950
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WO2008025941A3 (fr
Inventor
Sofia Loana Pascu
Philip Alan Waghorn
Grant Charles Churchill
Robert Braidwood Sim
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Isis Innovation Limited
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Publication of WO2008025941A3 publication Critical patent/WO2008025941A3/fr

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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C337/00—Derivatives of thiocarbonic acids containing functional groups covered by groups C07C333/00 or C07C335/00 in which at least one nitrogen atom of these functional groups is further bound to another nitrogen atom not being part of a nitro or nitroso group
    • C07C337/06—Compounds containing any of the groups, e.g. thiosemicarbazides
    • C07C337/08—Compounds containing any of the groups, e.g. thiosemicarbazides the other nitrogen atom being further doubly-bound to a carbon atom, e.g. thiosemicarbazones
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D453/00—Heterocyclic compounds containing quinuclidine or iso-quinuclidine ring systems, e.g. quinine alkaloids
    • C07D453/02—Heterocyclic compounds containing quinuclidine or iso-quinuclidine ring systems, e.g. quinine alkaloids containing not further condensed quinuclidine ring systems
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
    • C07F3/00—Compounds containing elements of Groups 2 or 12 of the Periodic Table
    • C07F3/003—Compounds containing elements of Groups 2 or 12 of the Periodic Table without C-Metal linkages

Definitions

  • the present invention relates to metal complexes of thiosemicarbazone derivatives and the uses of those complexes in medical imaging and therapy.
  • the present invention also relates to processes for producing the complexes of the invention and to pharmaceutical compositions comprising them.
  • Molecular imaging is a growing area of research. There is a wide interest in designing novel imaging probes for biological targets. Targets can then be imaged in vivo with a range of molecular imaging devices to attain research and clinical objectives.
  • Non-invasive techniques such as fluorescence imaging, PET (Positron Emission Tomography) and SPECT (Single Photon Emission Computerised Tomography), can be used to follow the mechanism of uptake and distribution of metal complexes of interest in terms of therapeutic and imaging applications. Fluorescence imaging can also be used to follow such molecules in living cells in vitro.
  • Bis(thiosemicarbazone) complexes of transition metals have been known for nearly 50 years. Despite demonstrations of biological activity, the mechanism of action of such complexes at the cellular level remains unknown. There is therefore an ongoing interest to synthesise such complexes and study their biological uptake, by, for example, fluorescence imaging. Indeed, there has been great interest in Cu(II) as a result of its role in biology, and the versatility in its radioactive isotopes. However, Cu(II) is d 9 paramagnetic and as a result tends to quench the fluorescence of adjacent fluorophores. This generally prevents direct fluorescent observation of the copper complexes of interest. By direct substitution with zinc, however, the ability to image via fluorescence is a practical possibility. Despite this, fluorescent, molecular zinc complexes are not well known.
  • the inventors have shown that a certain class of metal complexes are taken up into a range of human cancer cell lines and exhibit significant cytotoxicity towards those cell lines.
  • the metal complexes are therefore candidates for use as therapeutic agents, in particular for use in treating cancers and other conditions characterised by undesirable cellular proliferation.
  • complexes have the potential to be hypoxic selective and may therefore be suitable for therapy and/or imaging of hypoxic tumours. Additionally, or as an alternative to hypoxic selectivity, the complexes may be conjugated to a biologically active molecule which serves to target the complex to the desired site in vivo.
  • M is a transition metal or a p-block metal; either (i) n is 0, b is a bond and c is not a bond; (ii) n is 1 , b is not a bond and c is a bond; or (iii) n is 1 , b is a bond and c is not a bond; L is a ligand comprising an electron donor group; a is a Cs -10 carbocyclic, C 5-10 heterocyclic, C 5-10 aryl or C 5-10 heteroaryl ring, which ring is unsubstituted, substituted or part of a fused bi-, tri-, terra- or polycyclic ring system, wherein the or each further ring of said fused bi-, tri-, terra- or polycyclic ring system is independently selected from a C 5-1 O carbocyclic ring, a C 5-10 heterocyclic ring, a C 5-1O aryl ring and a C 5-10 heteroaryl
  • Ll and Ll' which are the same or different, are each independently selected from a covalent bond and a linker group selected from -alk ⁇ , -C(O)-, -alk-C(O)-, -C(O)O-,-alk- C(O)O-, -OC(O)-, -alk-OC(O)-, -0-, -alk-O-, -N(RJ)-, -alk-N(R7)-, -N(R7)C(0), -alk- N(R7)C(0)-, -C(0)N(R7), -alk-C(0)N(R7), -C(S)-, -alk-C(S)-, -S-, -alk-S- 5 -C(S)N(R7)-, - alk-C(S)N(R7)-, -N(R7)C(S)-, -alk-N(R7)C(S)
  • Z is a moiety selected from a biologically active molecule, a fluorophore, a cytotoxin, an amino acid, a peptide, an oligopeptide, a polypeptide, a sugar, a group containing a label, a leaving group which is replaceable by a group containing a label, and a complex of a transition metal with a bis(thiosemicarbazone) or a thiosemicarbazone;
  • R2 and R2' which are the same or different, are each independently selected from H and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, amino, C 1-10 alkylamino, di(C 1-1 o)alkylamino, C 3-2O carbocyclyl, C 3 .
  • -alk- is unsubstituted or substituted C 1-20 alkylene which is optionally interrupted by N(R7), O, S or arylene; and R7 is H, C 1-6 alkyl, C 3-10 cycloalkyl or aryl; provided that Ll, Rl and R2 may form, together with the N atom to which Ll and R2 are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; and provided that Ll ', Rl' and R2' may form, together with the N atom to which Ll ' and R2' are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group.
  • the invention further provides:
  • a method of treating a condition characterised by undesirable cellular proliferation comprises administering to a patient in need of such treatment an effective amount of a metal complex as defined above.
  • compositions for use in treating a condition characterised by undesirable cellular proliferation comprising a pharmaceutically acceptable carrier or diluent and a metal complex as defined above.
  • an agent for the treatment of a condition characterised by undesirable cellular proliferation comprising a metal complex as defined above.
  • the inventors have also found that the complexes defined above, including copper complexes, have enhanced fluorescence compared with known metal thiosemicarbazone compounds, and that the complexes possess intrinsic fluorescence.
  • the fluorescent properties of the complexes allows the distribution of the complexes within cells to be monitored.
  • the complexes defined above which are employed in the present invention may be radiolabeled with metastable metal radionuclides which are useful in medical imaging techniques such as PET (Positron Emission Tomography) and SPECT (Single Photon Emmission Computerised Tomography).
  • the complexes are candidates for use as imaging agents, using either a radioactive imaging technique such as PET or SPECT, or a non-radioactive optical technique, such as fluorescence.
  • the radiolabelled complexes may be suitable for both non-radioactive and radioactive imaging, which may be used in combination.
  • radioactive imaging techniques such as PET and SPECT could provide an extremely powerful tool in the clinical diagnosis and treatment of disease.
  • the complexes are candidates for use as dual therapy and imaging agents, for example in the treatment and imaging of cancer tumours and other conditions characterised by undesirable cellular proliferation.
  • the present invention further provides: a diagnostic agent or medical imaging agent which comprises a metal complex as defined above.
  • a diagnostic agent or medical imaging agent which comprises a metal complex as defined above in the manufacture of a medicament for use as a diagnostic agent, an imaging agent and/or a therapeutic agent.
  • a method of imaging a cell or in vitro biopsy sample which method comprises: (a) contacting the cell or in vitro biopsy sample with a metal complex of the invention as defined above; and (b) imaging the cell or in vitro biopsy sample.
  • a method of imaging a patient in need thereof which method comprises: (a) administering to the patient a metal complex of the invention as defined above; and (b) imaging the patient.
  • the invention further provides a metal complex of formula (I):
  • M is a transition metal or a p-block metal; either (i) n is 0, b is a bond and c is not a bond; (ii) n is 1, b is not a bond and c is a bond; or (iii) n is 1, b is a bond and c is not a bond; L is a ligand comprising an electron donor group; a is: (i) a C 5-10 carbocyclic, C 5-10 heterocyclic, C 5-I0 aryl or C 5-10 heteroaryl ring which is part of a fused bi-, tri-, tetra- or polycyclic ring system, wherein the or each further ring of said fused bi-, tri-, tetra- or polycyclic ring system is independently selected from a C 5-10 carbocyclic ring, a C 5-10 heterocyclic ring, a C 5-10 aryl ring and a C 5-10 heteroaryl ring, wherein at least one ring of
  • Y and Y' which are the same or different, are independently selected from S, O, N(R5) and P(R5), wherein each R5 is independently selected from H, C 1 -C 6 alkyl, phenyl and a group comprising an electron donor group, which donor group is separated by two carbon atoms from the N or P atom to which R5 is attached;
  • Ll and Ll' which are the same or different, are each independently selected from a covalent bond and a linker group selected from -alk-, -C(O)-, -alk-C(O)-, -C(O)O-,-alk- C(O)O-, -OC(O)-, -alk-OC(O)-, -O-, -alk-O-, -N(R7) ⁇ , -alk-N(R7)-, -N(R7)C(0), -alk- N(R7)C(O)-, -C(O)N(R
  • Z is a moiety selected from a biologically active molecule, a fluorophore, a cytotoxin, an amino acid, a peptide, an oligopeptide, a polypeptide, a sugar, a group containing a label, a leaving group which is replaceable by a group containing a label, and a complex of a transition metal with a bis(thiosemicarbazone) or a thiosemicarbazone;
  • R2 and R2' which are the same or different, are each independently selected from H and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, amino, C 1-10 alkylamino, di(C 1-10 )aIkylammo, C 3-20 carbocyclyl, C 3-20 heterocyclyl, C 3-2 O heteroaryl, aryl, aryloxy, -alk-C 3-2 o carbocyclyl, -alk-C 3-2 o heterocyclyl, -alk-C 3-2 o heteroaryl, and -alk-aryl, which C 1-20 alkyl, C 2-20 alkenyl and C 2-20 alkynyl are optionally interrupted by N(RT), O 5 S or arylene;
  • -alk- is unsubstituted or substituted C 1-20 alkylene which is optionally interrupted by N(RT), O, S or arylene;
  • R7 is H, C 1-6 alkyl, C 3-10 cycloalkyl or aryl; provided that Ll, Rl and R2 may form, together with the N atom to which Ll and R2 are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; and provided that Ll' , Rl ' and R2' may form, together with the N atom to which Ll ' and R2' are attached, an unsubstituted or substituted C 3 _ 20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group.
  • the invention further provides a pharmaceutical composition comprising a metal complex of the invention as defined above and a pharmaceutically acceptable carrier.
  • the invention further provides a metal complex of formula (I):
  • M is a transition metal or a p-block metal; either (i) n is O 5 b is a bond and c is not a bond; (ii) n is 1 , b is not a bond and c is a bond; or (iii) n is 1, b is a bond and c is not a bond;
  • L is a ligand comprising an electron donor group;
  • a is: (i) a C 5-10 carbocyclic, C 5-10 heterocyclic, C 5-10 aryl or C 5-10 heteroaryl ring which is part of a fused bi-, tri-, tetra- or polycyclic ring system, wherein the or each further ring of said fused bi- 5 tri-, tetra- or polycyclic ring system is independently selected from a C 5-10 carbocyclic ring, a C 5-10 heterocyclic ring, a C 5-10 aryl ring and a C 5-10 heteroaryl ring, wherein the ring system is unsubstituted or substituted; (ii) an unsubstituted or substituted C 5 . 10 aryl ring; or (iii) an unsubstituted or substituted C 5-10 heteroaryl ring;
  • X and X' which are the same or different, are independently selected from N and P;
  • Y and Y' which are the same or different, are independently selected from S, O, N(R5) and P(R5), wherein each R5 is independently selected from H, C 1 -C 6 alkyl, phenyl and a group comprising an electron donor group, which donor group is separated by two carbon atoms from the N or P atom to which R5 is attached;
  • Ll and Ll' which are the same or different, are each independently selected from a covalent bond and a linker group selected from -alk-, -C(O)-, -alk-C(O)-, -C(O)O-,-alk- C(O)O-, -OC(O)-, -alk-OC(O)-, -O-, -alk-O-, -N(R7)-, -alk-N(R7)-, -N(R7)C(O), -alk- N(R7)C(0)-, -C(O)N(R7), -alk-C(O)N(R7), -alk-C(O)N(R7), -C(S)-, -alk-C(S)-, -S-, -alk-S-, -C(S)N(R7)-, - alk-C(S)N(R7)-, -N(R7)
  • Z is a moiety selected from a biologically active molecule, a fluorophore, a cytotoxin, an amino acid, a peptide, an oligopeptide, a polypeptide, a sugar, a group containing a label, a leaving group which is replaceable by a group containing a label, and a complex of a transition metal with a bis(thiosemicarbazone) or a thiosemicarbazone;
  • R2 and R2' which are the same or different, are each independently selected from H and a substituted or unsubstituted group selected from Ci -20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, amino, Ci -I0 alkylamino, di(C 1-10 )alkylamino, C 3-20 carbocyclyl, C 3-20 heterocyclyl, C 3-20 heteroaryl, aryl, aryloxy, -alk-C 3 .
  • -alk- is unsubstituted or substituted C 1-20 alkylene which is optionally interrupted by N(RT), O, S or arylene;
  • R7 is H, C 1-6 alkyl, C 3-10 cycloalkyl or aryl; provided that Ll, Rl and R2 may form, together with the N atom to which Ll and R2 are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; and provided that Ll ', Rl ' and R2' may form, together with the N atom to which Ll ' and R2' are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group.
  • the invention further provides a pharmaceutical composition comprising a metal complex as defined above and a pharmaceutically acceptable carrier.
  • the invention further provides processes for producing the metal complexes employed in the present invention.
  • the invention provides a process for producing a metal complex of the following formula (Ia):
  • M is a transition metal or a p-block metal;
  • a is a C 5-10 carbocyclic, C 5-10 heterocyclic, C 5-10 aryl or C 5-10 heteroaryl ring, which ring is unsubstituted, substituted or part of a fused bi-, tri-, tetra- or polycyclic ring system, wherein the or each further ring of said fused bi-, tri-, tetra- or polycyclic ring system is independently selected from a C 5-10 carbocyclic ring, a C 5-1O heterocyclic ring, a C 5-10 aryl ring and a C 5-10 heteroaryl ring, wherein the ring system is unsubstituted or substituted;
  • X and X' which are the same or different, are independently selected from N and P; Y and Y', which are the same or different, are independently selected from S, O,
  • each R5 is independently selected from H, C 1 -C 6 alkyl, phenyl and a group comprising an electron donor group, which donor group is separated by two carbon atoms from the N or P atom to which R5 is attached;
  • Ll and Ll' which are the same or different, are each independently selected from a covalent bond and a linker group selected from -alk-, -C(O)-, -alk-C(O)-, -C(O)O-,-alk- C(O)O-, -OC(O)-, -alk-OC(O)-, -O-, -alk-O-, -N(R7)-, -alk-N(R7)-, -N(R7)C(0), -alk- N(R7)C(0)-, -C(O)N(R7), -alk-C(O)N(R7), -C(S)-, -alk-C(S)-, -S-, -alk-S-, -C(S)N(R7)-, - alk-C(S)N(R7)-, -N(R7)C(S)-, -alk-N(R7)
  • Rl and Rl ' which are the same or different, are each independently selected from hydrogen, Z, L3-Z, L3-alk-Z, and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, amino, C 1-10 alkylamino, di(C 1-10 )alkylamino, C 3-2O carbocyclyl, C 3-20 heterocyclyl, C 3-2O heteroaryl, aryl, aryloxy, -alk-C 3-2 o carbocycl
  • R2 and R2' which are the same or different, are each independently selected from H and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, amino, C 1-10 alkylamino, di(C 1-10 )alkylammo, C 3-20 carbocyclyl, C 3-20 heterocyclyl, C 3-20 heteroaryl, aryl, aryloxy, -alk-C 3-20 carbocyclyl, -alk-C 3-20 heterocyclyl, -alk-C 3 . 20 heteroaryl, and -alk-aryl, which C 1-20 alkyl, C 2-20 alkenyl and C 2-20 alkynyl are optionally interrupted by N(RT), O 5 S or arylene;
  • -alk- is unsubstituted or substituted C 1-20 alkylene which is optionally interrupted by N(RT), O, S or arylene; and R7 is H, C 1-6 alkyl, C 3-10 cycloalkyl or aryl; provided that Ll, Rl and R2 may form, together with the N atom to which Ll and R2 are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; and provided that Ll ', Rl ' and R2' may form, together with the N atom to which Ll ' and R2' are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; which process comprises treating, in the presence of a solvent, a salt of M with either:
  • M is a transition metal or a p-block metal;
  • a is a C 5-10 carbocyclic, C 5-1 o-heterocyclic, C 5-10 aryl or C 5-I0 heteroaryl ring, which ring is unsubstituted, substituted or part of a fused bi- 5 tri-, tetra- or polycyclic ring system, wherein the or each further ring of said fused bi-, tri-, tetra- or polycyclic ring system is independently selected from a C 5-10 carbocyclic ring, a C 5-10 heterocyclic ring, a C 5-10 aryl ring and a C 5-10 heteroaryl ring, wherein the ring system is unsubstituted or substituted;
  • X and X' which are the same or different, are independently selected from N and P; Y and Y', which are the same or different, are independently selected from S, O,
  • each R5 is independently selected from H, C 1 -C 6 alkyl, phenyl and a group comprising an electron donor group, which donor group is separated by two carbon atoms, from the N or P atom to which R5 is attached;
  • Ll and Ll' which are the same or different, are each independently selected from a covalent bond and a linker group selected from -alk-, -C(O)-, -alk-C(O)-, -C(O)O-,-alk- C(O)O-, -OC(O)-, -alk-OC(O)-, -0-, -alk-O-, -N(R7)-, -alk-N(R7)- 5 -N(R7)C(0), -alk- N(R7)C(O)-, -C(O)N(R7), -alk-C(O)N(R7), -alk-C(O)N(R7), -C(S)-, -alk-C(S)-, -S-, -alk-S-, -C(S)N(R7)-, - alk-C(S)N(R7)-, -N(R7)
  • Rl and Rl' which are the same or different, are each independently selected from hydrogen, Z, L3-Z, L3-alk-Z, and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, amino, Ci -10 alkylamino, di(Ci -10 )alkylarnino, C 3-20 carbocyclyl, C 3-20 heterocyclyl, C 3-20 heteroaryl, aryl, aryloxy, -alk-C 3-2 o carbocycl
  • Z is a moiety selected from a biologically active molecule, a fluorophore, a cytotoxin, an amino acid, a peptide, an oligopeptide, a polypeptide, a sugar, a group containing a label, a leaving group which is replaceable by a group containing a label, and a complex of a transition metal with a bis(thiosemicarbazone) or a thiosemicarbazone;
  • R2 and R2' which are the same or different, are each independently selected from H and a substituted or unsubstituted group selected from C 1 J 20 alkyl, C 2 -20 alkenyl, C 2-20 alkynyl, amino, C 1-10 alkylamino, di(C 1-10 )alkylamino, C 3-20 carbocyclyl, C 3-2 o heterocyclyl, C 3-2 O heteroaryl, aryl, aryloxy, -alk-C 3-20 carbocyclyl, -alk-C 3-20 heterocyclyl, -alk-C 3-20 heteroaryl, and -alk-aryl, which C 1-20 alkyl, C 2-20 alkenyl and C 2-20 alkynyl are optionally interrupted by N(RT), O, S or arylene;
  • -alk- is unsubstituted or substituted C 1-20 alkylene which is optionally interrupted by N(RT), O, S or arylene; and R7 is H, C 1-6 alkyl, C 3-10 cycloalkyl or aryl; provided that Ll , Rl and R2 may form, together with the N atom to which Ll and R2 are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3 .
  • Ll', Rl ' and R2' may form, together with the N atom to which Ll ' and R2' are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; which process comprises treating a salt of M, in the presence of a solvent, with a metal complex of the following formula (W):
  • M' is a metal other than M and is either (i) a transition metal or (ii) a main group metal; and a, X', X, Y', Y 5 R2, R2 ⁇ Rl 3 Rl', Ll and Ll' are as defined above for the metal complex of formula (Ia).
  • the invention further provides a process for producing a metal complex of the following formula (Ib):
  • M is a transition metal or a p-block metal; either (i) b is a bond and c is not a bond, or (ii) c is a bond and b is not a bond; L is a ligand comprising an electron donor group; a is a C 5-1O carbocyclic, C 5-10 heterocyclic, Cs -10 aryl or C 5-1 O heteroaryl ring, which ring is unsubstituted, substituted or part of a fused bi-, tri-, terra- or polycyclic ring system, wherein the or each further ring of said fused bi-, tri-, tetra- or polycyclic ring system is independently selected from a C 5-10 carbocyclic ring, a C 5-10 heterocyclic ring, a C 5 . 10 aryl ring and a C 5-1O heteroaryl ring, wherein the ring system is unsubstituted or substituted;
  • X and X' which are the same or different, are independently selected from N and P;
  • Y and Y' which are the same or different, are independently selected from S 5 O 5 N(R5) and P(R5), wherein each R5 is independently selected from H 5 C 1 -C 6 alkyl, phenyl and a group comprising an electron donor group, which donor group is separated by two carbon atoms from the N or P atom to which R5 is attached;
  • Ll and Ll ' which are the same or different, are each independently selected from a covalent bond and a linker group selected from -alk-, -C(O)-, -alk-C(O)-, -C(O)O-,-alk- C(O)O-, -OC(O)-, -alk-OC(O)-, -O-, -alk-O-, -N(R7)-, -alk-N(R7)-, -N(R7)C(0), -alk-
  • Z is a moiety selected from a biologically active molecule, a fluorophore, a cytotoxin, an amino acid, a peptide, an oligopeptide, a polypeptide, a sugar, a group containing a label, a leaving group which is replaceable by a group containing a label, and a complex of a transition metal with a bis(thiosemicarbazone) or a thiosemicarbazone;
  • R2 and R2' which are the same or different, are each independently selected from H and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, amino, C 1-10 alkylamino, di(C 1 .
  • C 1 o)alkylamino C 3-20 carbocyclyl, C 3-20 heterocyclyl, C 3-20 heteroaryl, aryl, aryloxy, -alk-C 3-20 carbocyclyl, -alk-C 3-20 heterocyclyl, -alk-C 3-2 o heteroaryl, and -alk-aryl, which C 1-20 alkyl, C 2-20 alkenyl and C 2-20 alkynyl are optionally interrupted by N(R7), O, S or arylene;
  • -alk- is unsubstituted or substituted C 1-20 alkylene which is optionally interrupted by N(R7), O, S or arylene; and R7 is H, C 1-6 alkyl, C 3-10 cycloalkyl or aryl; provided that Ll, Rl and R2 may form, together with the N atom to which Ll and R2 are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; and provided that Ll ', Rl' and R2' may form, together with the N atom to which Ll ' and R2' are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; the process comprising treating a compound of formula (Ia) as defined above, with either: (i) L; or
  • Fig. Ia is a graph of fluorescence intensity (y axis) versus wavelength in units of nm (x axis) for (a) the acenaphthenequinone-derived Zn complex 14 (solid line) and (b) the corresponding butadiene-derived complex Zn(ATSPh) (dotted line) in DMSO at concentrations of O.OlmM.
  • Fig. Ib is a graph of fluorescence intensity (y axis) versus wavelength in units of nm
  • Fig. 2 is a graph of fluorescence intensity (y axis) versus wavelength in units of nm (x axis) for compound 13 dissolved in (a) DMSO at a concentration of O.OlmM (solid line), and (b) a 5:95 DMSOrwater mix at a concentration of 0. ImM (dashed line).
  • Fig. 3 is an energy diagram showing the relative energies in eV (y axis) of the DFT- calculated frontier orbitals (HOMO(-l), HOMO and LUMO) for Zn complex 12, and the nature of the electron density on those frontier orbitals.
  • Fig. 4 is a graph of absorbance (y axis) versus wavelength in units of nm (x axis) for
  • Zn complex 12 solid line
  • Zn(ATSM) dashed line
  • Fig. 5 shows an IGROV cell fluorescence uptake image (a) and the corresponding bright field image (b) for compound 12, and an IGROV cell fluorescence uptake image (c) and the corresponding bright field image (d) for compound 14.
  • Fig. 6 is a graph of fluorescence uptake intensity (y axis) versus time in units of minutes (x axis) for compound 12 in IGROV cells.
  • Fig. 7 shows IGROV cell fluorescence uptake images for compound 13, both without lysotracker (a) and with lysotracker (b), and the corresponding bright field image (c).
  • Fig. 8 is a graph of fluorescence uptake intensity (y axis) versus time in units of minutes (x axis) for compound 13 in IGROV cells.
  • Fig. 9 shows S W620 cell fluorescence uptake images (left) and the corresponding bright field images (right) for compounds 12 (a) 13 (b) and 14 (c).
  • Fig. 10a is a graph of fluorescence uptake intensity (y axis) versus time in units of minutes (x axis) for compound 13 in SW620 cells.
  • Fig. 10b is a graph of fluorescence uptake intensity (y axis) versus time in units of minutes (x axis) for compound 14 in SW620 cells.
  • Fig. 11 shows A431 cell fluorescence uptake images (left) and the corresponding bright field images (right) for compounds 12 (a) 13 (b) and 14 (c).
  • Fig. 12a is a graph of fluorescence uptake intensity (y axis) versus time in units of minutes (x axis) for compound 13 in A431 cells.
  • Fig. 12b is a graph of fluorescence uptake intensity (y axis) versus time in units of minutes (x axis) for compound 14 in A431 cells.
  • Fig. 13 shows a T24 cell fluorescence uptake image (a) and the corresponding bright field image (b) for compound 13, and a T24 cell fluorescence uptake image (c) and the corresponding bright field image (d) for compound 14.
  • Fig. 14a is a graph of fluorescence uptake intensity (y axis) versus time in units of minutes (x axis) for compound 13 in T24 cells.
  • Fig. 14b is a graph of fluorescence uptake intensity (y axis) versus time in units of minutes (x axis) for compound 14 in T24 cells.
  • Fig. 15 is a histogram showing the cytotoxic effect of compounds 12, 13 and 14 on U937 cells with respect to a 1% DMSO standard and medium standard.
  • the histogram shows the number of live U937 cells after 48 hours in units of 10 s cells/ml (y axis) after incubation (a) with medium alone, (b) with 1 :99 DMSO:medium solution, (c) with lOO ⁇ M compound 12 in 1:99 DMSO medium, (d) with lOO ⁇ M compound 13 in 1:99 DMSO:medium and (e) with lOO ⁇ M compound 14 in 1:99 DMSO:medium.
  • Fig. 16 is a histogram showing the cytotoxic effect of compound 13 on SW620 cells over a range of concentrations, with respect to a 1 % DMSO standard and medium standard.
  • the histogram shows the number of live SW620 cells after 48 hours in units of 10 5 cells/ml (y axis) after incubation (a) with medium alone, (b) with 1:99 DMSO:medium solution, (c) with lOO ⁇ M compound 13 in 1:99 DMSO:medium, (d) with 50 ⁇ M compound 13 in 1:99 DMSO:medium, (e) with 25 ⁇ M compound 13 in 1 :99 DMSO:medium and (f) with 12.5 ⁇ M compound 13 in 1 : 99 DMSO :medium.
  • Fig. 17 is a histogram showing the cytotoxic effect of compound 13 on T24 cells over a range of concentrations, with respect to a 1% DMSO standard and medium standard.
  • the histogram shows the number of live T24 cells after 48 hours in units of 10 5 cells/ml (y axis) after incubation (a) with medium alone, (b) with 1 :99 DMSO:medium solution, (c) with 50 ⁇ M compound 13 in 1:99 DMSOmedium, (d) with 25 ⁇ M compound 13 in 1:99 DMSO:medium, (e) with 12.5 ⁇ M compound 13 in 1:99 DMSOmedium and (f) with 6.5 ⁇ M compound 13 in 1 :99 DMSO:medium.
  • Fig. 17 shows the number of live T24 cells after 48 hours in units of 10 5 cells/ml (y axis) after incubation (a) with medium alone, (b) with 1 :99 DMSO:medium solution, (c) with 50 ⁇ M compound 13
  • 18 is a histogram showing the cytotoxic effect of compound 13 on A431 cells over a range of concentrations, with respect to a 1% DMSO standard and medium standard.
  • the histogram shows the number of live A431 cells after 48 hours in units of 10 5 cells/ml (y axis) after incubation (a) with medium alone, (b) with 1 :99 DMSO:medium solution, (c) with lOO ⁇ M compound 13 in 1:99 DMSOmedium, (d) with 50 ⁇ M compound 13 in 1:99 DMSOmedium, (e) with 25 ⁇ M compound 13 in 1 :99 DMSOmedium and (f) with 12.5 ⁇ M compound 13 in 1:99 DMSOmedium.
  • Fig. 19 is a histogram comparing the cytotoxic effects of compounds 13, 16 and cis platin, at a range of concentrations, on IGROV cells with respect to a 1% DMSO standard and medium standard.
  • the histogram shows the number of live IGROV cells after 48 hours in units of 10 5 cells/ml (y axis) after incubation (a) with medium alone, (b) with 1 :99
  • Fig. 20 shows (a) a full voltammagram sweep for compound 15 and (b) the enlarged reduction wave of the Cu(II)/Cu(I) couple, at a scan rate of 100mV/s.
  • voltage (V) is given on the y axis and current (A) is given on the x axis.
  • Fig. 21 shows (a) a full voltammagram sweep for compound 16 and (b) the enlarged reduction wave of the Cu(II)/Cu(I) couple, at a scan rate of 100mV/s.
  • voltage (V) is given on the y axis and current (A) is given on the x axis.
  • Fig. 23 is a graph of fluorescence intensity (y axis) versus wavelength in units of nm (x axis) for (a) the Cu complex 15 (solid line), and (b) the acenaphthenequinone-derived Zn complex 12 (dashed line) in 100% DMSO at concentrations of 0. ImM.
  • Fig. 24 shows an IGROV cell fluorescence uptake image (a) and the corresponding bright field image (b) for compound 16.
  • Fig. 25 is an HPLC trace of complex 13 after radiolabelling with 64 Cu.
  • the y axis represents counts per second and the x axis represents time in units of minutes.
  • Fig. 26 is a graph of fluorescence intensity (y axis) versus wavelength in units of nm (x axis) for complexes 17, 18 and 21 ( ⁇ ex 480 nm, DMSO 100 ⁇ M).
  • Fig. 27 is a graph of fluorescence intensity (y axis) versus wavelength in units of nm
  • Figs. 28a and 28b show epifluorescence imaging of 18 in HeLa cells; Fig. 28a is an image taken 60 minutes after loading of 18; Fig. 28b is a bright field image (scale bar ca. 150 ⁇ m).
  • Figs. 29a, 29b, 29c and 29d show confocal fluorescence imaging of 18 in MCF-7 (breast cancer carcinoma) cells.
  • Fig. 29a shows cells incubated with 18 at 4° C for 3h.
  • Fig. 29b shows cells incubated with 18 at 37° C for 3h.
  • Fig. 29c shows a bright field image of cells incubated with 18 at 4° C for 3h (scale bar ca. 200 ⁇ m).
  • Fig 29d shows a bright field image of cells incubated with 18 at 37° C for 3h (scale bar ca. 200 ⁇ m).
  • Figs. 30a, 30b and 30c relate to confocal fluorescence imaging of 18 in IGROV cells.
  • Fig. 30a is an image taken 90 minutes after loading with 18 at room temperature.
  • Fig. 30b is a bright field image (scale bar ca. 200 ⁇ m).
  • Fig. 30c is a graph of fluorescence intensity (y axis) versus time in units of minutes (x axis), and shows three uptake profiles of 18 in three different IGROV cells from 0 to 90 minutes (photobleaching occurred after 60 min in each case).
  • Fig. 30a, 30b and 30c relate to confocal fluorescence imaging of 18 in IGROV cells.
  • Fig. 30a is an image taken 90 minutes after loading with 18 at room temperature.
  • Fig. 30b is a bright field image (scale bar ca. 200 ⁇ m).
  • Fig. 30c is a graph of fluorescence intensity (y axis) versus time in units of minutes (x axis), and shows
  • 31 is a histogram comparing the cytotoxic effects of compounds 18, 21 and cis platin, at a range of concentrations, on MCF-7 cells with respect to a DMS O -.medium standard and a medium standard.
  • the histogram shows the number of live MCF-7 cells after 48 hours in units of 10 s cells/ml (y axis) after incubation (A) with medium alone, (B) with 1:99 DMSO:medium solution, (C) with 100 ⁇ M compound 18 in 1:99 DMSO:medium, (D) with 50 ⁇ M compound 18 in 1:99 DMS O medium, (E) with 25 ⁇ M compound 18 in 1:99 DMSOmedium, (F) with 12.5 ⁇ M compound 18 in 1:99 DMSO:medium, (G) with 100 ⁇ M compound 21 in 1 :99 DMSO:medium, (H) with 50 ⁇ M compound 21 in 1 :99 DMSO:medium, (I) with 25 ⁇ M compound 21 in 1 :99 DM
  • Fig. 32 shows (a) a radio HPLC trace, and (b) a UV HPLC trace of complex 18 after radiolabelling with 64 Cu by transmetallation.
  • Graph (a) is of intensity in units of counts per second (y axis) versus time in units of minutes (x axis).
  • Graph (b) is of intensity in units of mV (y axis) versus time in units of minutes (x axis).
  • Fig. 33 shows two graphs (a) and (b) of fluorescence intensity (y axis) versus wavelength in units of nm (x axis) for (a) the Zn complex 18 and compound D at lOO ⁇ M in DMSO, and (b) the Zn complex 18 and compound D at l ⁇ M in DMSO.
  • E OV (top spectrum)
  • E -1.2V (right spectrum)
  • E OV (bottom spectrum)
  • E +1 V (left spectrum).
  • the x axis represents B in units of mT and the y axis represents amplitude (a.u.).
  • Fig. 35 shows an X-band (9.450 GHz) cw-EPR spectrum of 16 (powder; 295 K) and its simulation.
  • the x axis represents B in units of mT.
  • Fig. 36 shows a graph of fluorescence intensity (y axis) versus wavelength in units of nm (x axis) for the copper complexes 15, 16 and 21.
  • Fig. 37 is a histogram comparing the cytotoxic effects of compounds 13, 16 and cis platin, at a range of concentrations, on MCF-7 cells with respect to a DMSOmedium standard and a medium standard.
  • the histogram shows the number of live MCF-7 cells after 48 hours in units of 10 5 cells/ml (y axis) after incubation (A) with medium alone, (B) with 1 :99 DMSOmedium solution, (C) with 1 OO ⁇ M compound 13 in 1 :99 DMSOmedium, (D) with 50 ⁇ M compound 13 in 1 :99 DMSOmedium, (E) with 25 ⁇ M compound 13 in 1 :99 DMSOmedium, (F) with 12.5 ⁇ M compound 13 in 1:99 DMSOmedium, (G) with lOO ⁇ M compound 16 in 1:99 DMSOmedium, (H) with 50 ⁇ M compound 16 in 1:99 DMSOmedium, (I) with 25 ⁇ M compound 16 in 1:99 DMS
  • Fig. 39 shows a MCF-7 cell fluorescence uptake image (a) and the corresponding bright field image (b) for MCF-7 cells incubated at 37° C for 3h with compound 13 (Zn Et).
  • Fig. 40 shows a MCF-7 cell fluorescence uptake image (a) and the corresponding bright field image (b) for MCF-7 cells incubated at 37° C for 12 h with compound 13 (Zn Et). Uptake in the nucleus as well as in the cytoplasm was observed. Advanced cell death was observed.
  • Fig. 41 shows a MCF-7 cell fluorescence uptake image (a) and the corresponding bright field image (b) for MCF-7 cells incubated at 4° C for 3h with compound 18 (Zn allyl).
  • Fig. 42 shows a MCF-7 cell fluorescence uptake image (a) and the corresponding bright field image (b) for MCF-7 cells incubated at 37° C for 3h with compound 18 (Zn allyl).
  • Fig. 43 shows a schematic diagram of a possible mechanism of uptake and localisation of the compounds in cells, as evidenced by Example 41 below, in which 1 represents endocytosis, 2 represents localisation to mitochondria, 3 represents mitochondrial disruption and 4 represents nuclear localisation.
  • a C 1-2O alkyl group is an unsubstituted or substituted, straight or branched chain saturated hydrocarbon radical. Typically it is C 1-10 alkyl, for example methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl or decyl, or C 1-6 alkyl, for example methyl, ethyl, propyl, butyl, pentyl or hexyl, or C M alkyl, for example methyl, ethyl, i-propyl, n-propyl, t- butyl, s-butyl or n-butyl.
  • alkyl group When an alkyl group is substituted it typically bears one or more (e.g. one to four) substituents selected from substituted or unsubstituted C 1-20 alkyl; substituted or unsubstituted aryl; substituted or unsubstituted aralkyl; cyano; amino; C 1-10 alkylamino; di(C 1-1 o)alkylamino; arylamino; diarylamino; arylalkylamino; nitro; amido; acylamido; hydroxyl; keto; halo; carboxy; ester; acyl; acyloxy; C 1-10 alkoxy; aryloxy; haloalkyl; sulfhydryl (i.e.
  • substituted alkyl groups include haloalkyl, hydroxyalkyl, aminoalkyl, alkoxyalkyl and alkaryl groups.
  • alkaryl as used herein, pertains to a C 1-20 alkyl group in which at least one hydrogen atom (e.g., 1, 2, 3) has been replaced with an aryl group.
  • a C 2-20 alkenyl group or moiety is a straight or branched group or moiety, which contains from 2 to 20 carbon atoms. One or more double bonds may be present in the alkenyl group or moiety, typically one double bond.
  • a C 2-20 alkenyl group or moiety is typically ethenyl or a C 3-10 alkenyl group or moiety.
  • a C 3-10 alkenyl group or moiety is typically a C 3-6 alkenyl group or moiety, for example allyl, propenyl, butenyl, pentenyl or hexenyl.
  • a C 2-4 alkenyl group or moiety is ethenyl, propenyl or butenyl.
  • An alkenyl group may be unsubstituted or substituted by one to four substituents, the substituents, unless otherwise specified, being selected from those listed above for C 1-20 alkyl groups. Where two or more substituents are present, these may be the same or different.
  • a C 2-20 alkynyl group or moiety is a straight or branched group or moiety which, unless otherwise specified, contains from 2 to 20 carbon atoms.
  • One or more triple bonds, and optionally one or more double bonds may be present in the alkynyl group or moiety, typically one triple bond.
  • a C 2-20 alkynyl group or moiety is typically ethynyl or a C 3-10 alkynyl group or moiety.
  • a C 3-1O alkynyl group or moiety is typically a C 3-6 alkynyl group or moiety, for example propynyl, butynyl, pentynyl or hexynyl.
  • a C 2-4 alkynyl group or moiety is ethynyl, propynyl or butynyl.
  • An alkynyl group may be unsubstituted or substituted by one to four substituents, the substituents, unless otherwise specified, being selected from those listed above for C 1 ⁇ o alkyl groups. Where two or more substituents are present, these may be the same or different.
  • a C 5-10 carbocyclic ring is a closed ring of from 5 to 10 covalently linked carbon atoms, which ring is saturated or unsaturated. Typically, the C 5-10 carbocyclic ring is not an aromatic ring. Typically the C 5-10 carbocyclic ring is a C 5-6 carbocyclic ring.
  • the carbocyclic ring may be saturated or unsaturated.
  • C 5-10 carbocyclic ring includes the sub- classes C 5-10 cycloalkyl ring, C 5-1O cycloalkyenyl ring and C 5-10 cycloalkynyl ring.
  • a C 5- 10 carbocyclic ring When a C 5- 10 carbocyclic ring is substituted it typically bears one or more substituents selected from those listed above for C 1-20 alkyl groups.
  • C 5-10 carbocyclic rings include, but are not limited to: cyclopentane (C 5 ), cyclohexane (C 6 ), cycloheptane (C 7 ), methylcyclopropane (C 4 ), dimethylcyclopropane (C 5 ), methylcyclobutane (C 5 ), dimethylcyclobutane (C 6 ), methylcyclopentane (C 6 ), dimethylcyclopentane (C 7 ), methylcyclohexane (C 7 ), dimethylcyclohexane (C 8 ), menthane (C 1O ), cyclopentene (C 5 ), cyclopentadiene (C 5 ), cyclohexene (C 6 ), cyclohexadiene (C 6 ), methylcyclopropene (C 4 ), dimethylcyclopropene (C 5 ), methylcyclobutene (C 5 ), dimethylcyclobutene (C 6 ),
  • a C 5-10 heterocyclic ring is a closed ring of from 5 to 10 covalently linked atoms, which ring is saturated or unsaturated, wherein at least one of the ring atoms is a multivalent ring heteroatom, for example, nitrogen, phosphorus, silicon, oxygen, or sulfur (though more commonly nitrogen, oxygen, or sulfur).
  • the C 5-1 O heterocyclic ring is not an aromatic ring.
  • the C 5-10 heterocyclic ring has from 1 to 4 heteroatoms, the remainder of the ring atoms are carbon.
  • the C 5-10 heterocyclic ring is a C 5-6 heterocyclic ring in which from 1 to 4 of the ring atoms are ring heteroatoms, and the remainder of the ring atoms are carbon atoms.
  • the prefixes C 5-10 and C 5-6 denote the number of ring atoms, or range of number of ring atoms.
  • Examples of monocyclic C 5-10 heterocyclic rings include, but are not limited to: N 1 : pyrrolidine (tetrahydropyrrole) (C 5 ), pyrroline (e.g., 3-pyrroline, 2,5-dihydropyrrole) (C 5 ), 2H-pyrrole or 3H-pyrrole (isopyrrole, isoazole) (C 5 ), piperidine (C 6 ), dihydropyridine (C 6 ), tetrahydropyridine (C 6 ), azepine (C 7 );
  • N 1 pyrrolidine (tetrahydropyrrole) (C 5 ), pyrroline (e.g., 3-pyrroline, 2,5-dihydropyrrole) (C 5 ), 2H-pyrrole or 3H-pyrrole (isopyrrole, isoazole) (C 5 ), piperidine (C 6 ), dihydropyridine (C 6 ), tetrahydropyr
  • O 1 oxolane (tetrahydrofuran) (C 5 ), oxole (dihydrofuran) (C 5 ), oxane (tetrahydropyran) (C 6 ), dihydropyran (C 6 ), pyran (C 6 ), oxepin (C 7 ); S 1 : thiolane (tetrahydrothiophene) (C 5 ), thiane (tetrahydrothiopyran) (C 6 ), thiepane
  • O 3 trioxane (C 6 ); N 2 : imidazolidine (C 5 ), pyrazolidine (diazolidine) (C 5 ), imidazoline (C 5 ), pyrazoline
  • N 1 O 1 tetrahydrooxazole (C 5 ), dihydrooxazole (C 5 ), tetrahydroisoxazole (C 5 ), dihydroisoxazole (C 5 ), morpholine (C 6 ), tetrahydrooxazine (C 6 ), dihydro ⁇ xazine (C 6 ), oxazine (C 6 ); N 1 S 1 : thiazoline (C 5 ), thiazolidine (C 5 ), thiomorpholine (C 6 );
  • O 1 S 1 oxathiole (C 5 ) and oxathiane (thioxane) (C 6 ); and,
  • N 1 O 1 S 1 oxathiazine (C 6 ).
  • a C 5-10 aryl ring is an aromatic ring of from 5 to 10 covalently linked carbon atoms.
  • the C 5-10 aryl ring is a C 5-6 aryl ring, examples of which include cyclopentadienyl (Cp) and phenyl.
  • a C 5-10 heteroaryl ring is a heteroaromatic ring of from 5 to 10 covalently linked atoms including one or more heteroatoms.
  • the one or more heteroatoms are typically selected from nitrogen, phosphorus, silicon, oxygen and sulfur (more commonly from nitrogen, oxygen and sulfur).
  • a C 5-1O heteroaryl ring is typically a 5- or 6-membered ring (i.e. a C 5-6 heteroaryl ring) containing at least one heteroatom selected from nitrogen, phosphorus, silicon, oxygen and sulfur (more commonly selected from nitrogen, oxygen and sulfur). It may contain, for example, 1, 2 or 3 heteroatoms.
  • heteroaryl rings examples include pyridine, pyrazine, pyrimidine, pyridazine, furan, thiofuran, pyrazole, pyrrole, oxazole, oxadiazole, isoxazole, thiadiazole, thiazole, isothiazole, imidazole and pyrazole.
  • the prefixes C 5-10 and C 5-6 denote the number of ring atoms, or range of number of ring atoms.
  • a C 3-2 O carbocyclyl group is an unsubstituted or substituted monovalent moiety obtained by removing a hydrogen atom from an alicyclic ring atom of a carbocyclic ring of a carbocyclic compound, which moiety has from 3 to 20 carbon atoms (unless otherwise specified), including from 3 to 20 ring atoms.
  • the carbocyclyl ring may be saturated or unsaturated.
  • the term "carbocyclyl” includes the sub-classes cycloalkyl, cycloalkyenyl and cycloalkynyl.
  • each ring has from 5 to 7 ring atoms.
  • Examples of groups of C 3-20 carbocyclyl groups include C 3-10 carbocyclyl, C 5-7 carbocyclyl and C 5-6 carbocyclyl. When a C 3-20 carbocyclyl group is substituted it typically bears one or more substituents selected from those listed above for C 1-20 alkyl groups.
  • C 3-10 carbocyclyl groups include, but are not limited to, those derived from saturated monocyclic hydrocarbon compounds: cyclopropane (C 3 ), cyclobutane (C 4 ), cyclopentane (C 5 ), cyclohexane (C 6 ), cycloheptane (C 7 ), methylcyclopropane (C 4 ), dimethylcyclopropane (C 5 ), methylcyclobutane (C 5 ), dimethylcyclobutane (C 6 ), methylcyclopentane (C 6 ), dimethylcyclopentane (C 7 ), methylcyclohexane (C 7 ), dimethylcyclohexane (C 8 ), menthane (C 10 ); unsaturated monocyclic hydrocarbon compounds : cyclopropene (C 3 ), cyclobutene (C 4 ), cyclopentene (C 5 ), cyclopentadiene (C 5 ), cyclohex
  • a C 3-1O cycloalkyl group or moiety is a 3- to 10- membered group or moiety, typically a 3 -to 6-membered group or moiety, which may be a monocyclic ring or which may consist of two or more fused rings.
  • Examples OfC 3-10 cycloalkyl groups or moieties include cyclopropane (C 3 ), cyclobutane (C 4 ), cyclopentane (C 5 ), cyclohexane (C 6 ), cycloheptane (C 7 ), methylcyclopropane (C 4 ), dimethylcyclopropane (C 5 ), methylcyclobutane (C 5 ), dimethylcyclobutane (C 6 ), methylcyclopentane (C 6 ), dimethylcyclopentane (C 7 ), methylcyclohexane (C 7 ), dimethylcyclohexane (C 8 ), menthane (C 10 ), thujane (C 10 ), carane (C 1O ), pinane (C 10 ), bornane (C 10 ), norcarane (C 7 ), norpinane (C 7 ), norbornane (C 7 ), adamantane (C 10 )
  • a C 3- 2o heterocyclyl group is an unsubstituted or substituted monovalent moiety obtained by removing a hydrogen atom from a ring atom of a heterocyclic compound, which moiety has from 3 to 20 ring atoms (unless otherwise specified), of which from 1 to 10 are ring heteroatoms.
  • each ring has from 3 to 7 ring atoms, of which from 1 to 4 are ring heteroatoms.
  • groups of heterocyclyl groups include C 3- 2oheterocyclyl,
  • C 5-20 heterocyclyl C 3-15 heterocyclyl, C 5-15 heterocyclyl, Cs- ⁇ heterocyclyl, Cs.nheterocyclyl, Cs-ioheterocyclyl, Cs -10 heterocyclyl, C 3-7 heterocyclyl, C 5-7 heterocyclyl, and Cs-eheterocyclyl.
  • Examples of (non-aromatic) monocyclic C 3-20 heterocyclyl groups include, but are not limited to, those derived from: N 1 : aziridine (C 3 ), azetidine (C 4 ), pyrrolidine (tetrahydropyrrole) (C 5 ), pyrroline (e.g.,
  • O 1 oxirane (C 3 ), oxetane (C 4 ), oxolane (tetrahydrofuran) (C 5 ), oxole (dihydrofuran) (Cs), oxane (tetrahydropyran) (C 6 ), dihydropyran (C 6 ), pyran (C 6 ), oxepin (C 7 ); S 1 : thiirane (C 3 ), thietane (C 4 ), thiolane (tetrahydrothiophene) (C 5 ), thiane
  • O 2 dioxolane (C 5 ), dioxane (C 6 ), and dioxepane (C 7 );
  • O 3 trioxane (C 6 );
  • N 2 imidazolidine (C 5 ), pyrazolidine (diazolidine) (C 5 ), imidazoline (C 5 ), pyrazoline (dihydropyrazole) (C 5 ), piperazine (C 6 );
  • N 1 O 1 tetrahydrooxazole (C 5 ), dihydrooxazole (C 5 ), tetrahydroisoxazole (C 5 ), dihydroisoxazole (C 5 ), morpholine (C 6 ), tetrahydrooxazine (C 6 ), dihydrooxazine (C 6 ), oxazine (C 6 );
  • N 1 S 1 thiazoline (C 5 ), thiazolidine (C 5 ), thiomorpholine (C 6 ); N 2 O 1 : oxadiazine (C 6 );
  • O 1 S 1 oxathiole (C 5 ) and oxathiane (thioxane) (C 6 ); and, N 1 O 1 S 1 : oxathiazine (C 6 ).
  • An aryl group is a substituted or unsubstituted, monocyclic, bicyclic or tricyclic aromatic group which typically contains from 6 to 14 carbon atoms, preferably from 6 to 10 carbon atoms in the ring portion. Examples include phenyl, naphthyl, indenyl, indanyl and anthracenyl groups.
  • An aryl group is unsubstituted or substituted. When an aryl group as defined above is substituted it typically bears one or more substituents selected from those listed above for C 1-20 alkyl groups. Typically it carries 0, 1, 2 or 3 substituents.
  • aralkyl as used herein, pertains to an aryl group in which at least one hydrogen atom (e.g., 1, 2, 3) has been substituted with a C ⁇ 20 alkyl group, which C 1-20 alkyl group is unsubstituted or substituted and optionally interrupted by N(R7), O, S or arylene, wherein R7 is as defined above.
  • R7 is as defined above.
  • examples of such groups include, but are not limited to, tolyl (from toluene), xylyl (from xylene), mesityl (from mesitylene), and cumenyl (or cumyl, from cumene), and duryl (from durene).
  • the ring atoms may include one or more heteroatoms, as in a heteroaryl group.
  • a heteroaryl group is a substituted or unsubstituted mono- or bicyclic heteroaromatic group which typically contains from 6 to 10 atoms in the ring portion including one or more heteroatoms. It is generally a 5- or 6-membered ring, containing at least one heteroatom selected from O, S, N, P, Se and Si. It may contain, for example, 1, 2 or 3 heteroatoms.
  • heteroaryl groups include pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, furanyl, thienyl, pyrazolidinyl, pyrrolyl, oxazolyl, oxadiazolyl, isoxazolyl, thiadiazolyl, thiazolyl, isothiazolyl, imidazolyl, pyrazolyl, quinolyl and isoquinolyl.
  • a heteroaryl group may be unsubstituted or substituted, for instance, as specified above for aryl. Typically it carries 0, 1, 2 or 3 substituents.
  • a C 1 - K alkylene group is an unsubstituted or substituted bidentate moiety obtained by removing two hydrogen atoms, either both from the same carbon atom, or one from each of two different carbon atoms, of a hydrocarbon compound having from 1 to 20 carbon atoms (unless otherwise specified), which may be aliphatic or alicyclic, and which may be saturated, partially unsaturated, or fully unsaturated.
  • alkylene includes the sub-classes alkenylene, alkynylene, cycloalkylene, etc., discussed below. Typically it is C 1-10 alkylene, for instance C 1-6 alkylene.
  • C 1-4 alkylene for example methylene, ethylene, i- propylene, n-propylene, t-butylene, s-butylene or n-butylene. It may also be pentylene, hexylene, heptylene, octylene and the various branched chain isomers thereof.
  • An alkylene group may be unsubstituted or substituted as specified above for C 1-20 alkyl.
  • C 1-4 alkylene refers to an alkylene group having from 1 to 4 carbon atoms.
  • groups of alkylene groups include C 1-4 alkylene ("lower alkylene”), C 1-7 alkylene, C 1-10 alkylene and C 1-20 alkylene.
  • linear saturated C 1-7 alkylene groups include, but are not limited to, -(CH 2 ) n - where n is an integer from 1 to 7, for example, -CH 2 - (methylene), -CH 2 CH 2 - (ethylene), -CH 2 CH 2 CH 2 - (propylene), and -CH 2 CH 2 CH 2 CH 2 - (butylene).
  • branched saturated C 1-7 alkylene groups include, but are not limited to, -CH(CH 3 )-, -CH(CH 3 )CH 2 -, -CH(CH 3 )CH 2 CH 2 -, -CH(CH 3 )CH 2 CH 2 CH 2 -,
  • alicyclic saturated C 1-7 alkylene groups include, but are not limited to, cyclopentylene (e.g., cyclopent-l,3-ylene), and cyclohexylene (e.g., cyclohex-l,4-ylene).
  • alicyclic partially unsaturated C 1-7 alkylene groups include, but are not limited to, cyclopentenylene (e.g., 4-cyclopenten-l,3-ylene), cyclohexenylene (e.g., 2-cyclohexen- 1 ,4-ylene; 3 -cyclohexen- 1 ,2-ylene; 2,5-cyclohexadien- 1 ,4-ylene).
  • cyclopentenylene e.g., 4-cyclopenten-l,3-ylene
  • cyclohexenylene e.g., 2-cyclohexen- 1 ,4-ylene; 3 -cyclohexen- 1 ,2-ylene; 2,5-cyclohexadien- 1 ,4-ylene.
  • An arylene group is an unsubstituted or substituted bidentate moiety obtained by removing two hydrogen atoms, one from each of two different aromatic ring atoms of an aromatic compound, which moiety has from 5 to 14 ring atoms (unless otherwise specified). Typically, each ring has from 5 to 7 or from 5 to 6 ring atoms.
  • An arylene group may be unsubstituted or substituted, for instance, as specified above for aryl.
  • the prefixes denote the number of ring atoms, or range of number of ring atoms, whether carbon atoms or heteroatoms.
  • C 5-6 arylene as used herein, pertains to an arylene group having 5 or 6 ring atoms.
  • groups of arylene groups include C 5-20 arylene, C 6-20 arylene, C 5-14 arylene, C 6-14 arylene, C 6-10 arylene, C 5-12 arylene, C 5-10 arylene, C 5-7 arylene, C 5-6 arylene, C 5 arylene, and C 6 arylene.
  • the ring atoms may be all carbon atoms, as in "carboarylene groups” (e.g., C 6-20 carboarylene, C 6-14 carboarylene or C 6-10 carboarylene).
  • C 6-20 arylene groups which do not have ring heteroatoms include, but are not limited to, those derived from the compounds discussed above in regard to aryl groups, e.g. phenylene, and also include those derived from aryl groups which are bonded together, e.g. phenylene-phenylene (diphenylene) and phenylene-phenylene-phenylene (triphenylene) .
  • the ring atoms may include one or more heteroatoms, as in "heteroarylene groups” (e.g., C 5-10 heteroarylene).
  • C 5-10 heteroarylene groups include, but are not limited to, those derived from the compounds discussed above in regard to heteroaryl groups.
  • halo is a group selected from -F, -Cl, -Br, and -I.
  • nitro represents a group of formula: -NO 2
  • R is an acyl substituent, for example, a substituted or unsubstituted C 1-20 alkyl group, a substituted or unsubstituted C 3-20 heterocyclyl group, or a substituted or unsubstituted aryl group.
  • R is an acyloxy substituent, for example, substituted or unsubstituted C 1-20 alkyl group, a substituted or unsubstituted C 3-20 heterocyclyl group, or a substituted or unsubstituted aryl group, typically a C 1-6 alkyl group.
  • ester represents a group of formula: -C(K))OR, wherein R is an ester substituent, for example, a C 1-6 alkyl group, a C 3-20 heterocyclyl group, or an aryl group (typically a phenyl group).
  • phosphonic acid represents a group of the formula: -P( ⁇ O)(OH) 2 .
  • phosphonic acid salt represents a group which is a salt of a phosphonic acid group.
  • X + may be an alkali metal cation.
  • X + may be Na + or K + , for example.
  • phosphate ester represents a group of one of the formulae:
  • each R is independently a phosphate ester substituent, for example, -H, substituted or unsubstituted C 1-20 alkyl, substituted or unsubstituted C3-20 heterocyclyl, C 3-20 heterocyclyl substituted with a further C 3-20 heterocyclyl, substituted or unsubstituted C 1-20 alkylene-C 3-20 heterocyclyl, substituted or unsubstituted C 3-25 cycloalkyl, substituted or unsubstituted C 1-20 alkylene-C 3-25 cycloalkyl, aryl, substituted or unsubstituted C 1-20 alkylene-aryl.
  • amino represents a group of formula -NH 2 .
  • C 1 -C 1O alkylamino represents a group of formula -NHR' wherein R' is a C 1-10 alkyl group, preferably a Ci-6 alkyl group, as defined previously.
  • di(C 1-1 o)alkylamino represents a group of formula -NR'R" wherein R' and R" are the same or different and represent C 1-10 alkyl groups, preferably C 1-6 alkyl groups, as defined previously.
  • arylamino represents a group of formula -NHR' wherein R' is an aryl group, preferably a phenyl group, as defined previously.
  • diarylamino represents a group of formula -NR'R" wherein R' and R" are the same or different and represent aryl groups, preferably phenyl groups, as defined previously.
  • arylalkylamino represents a group of formula -NR 'R" wherein R' is a C 1-10 alkyl group, preferably a Ci- 6 alkyl group, and R" is an aryl group, preferably a phenyl group.
  • a C 1-10 alkylthio group is an unsubstituted or substituted C 1-10 alkyl group, preferably a C 1-6 alkyl group, attached to a thio group.
  • An arylthio group is an unsubstituted or substituted aryl group, preferably a phenyl group, attached to a thio group.
  • a C 1-10 alkoxy group is a said C 1-10 alkyl group attached to an oxygen atom.
  • a C 1-6 alkoxy group is a said C 1-6 alkyl group attached to an oxygen atom.
  • a C 1-4 alkoxy group is a C 1-4 alkyl group attached to an oxygen atom.
  • Examples of C 1-4 alkoxy groups include, -OMe (methoxy), -OEt (ethoxy), -0(nPr) (n-propoxy), -O(iPr) (isopropoxy), -0(nBu) (n-butoxy), - O(sBu) (sec-butoxy), -O(iBu) (isobutoxy), and -O(tBu) (tert-butoxy).
  • An aryloxy group is an unsubstituted or substituted aryl group, preferably a phenyl group, attached to an oxygen atom.
  • An example of an aryloxy group is -OPh (phenoxy
  • 20 alkynyl groups as defined herein are either uninterrupted or interrupted by one or more heteroatoms or heterogroups, such as -S-, - O- or -N(R7)- wherein R7 is H, C 1-6 alkyl, C 3-10 cycloalkyl or aryl (typically phenyl), or by one or more arylene (typically phenylene) groups.
  • phrases "optionally interrupted” as used herein thus refers to a C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl or C 1-20 alkylene group, as defined above, which is uninterrupted or which is interrupted between adjacent carbon atoms by a heteroatom such as oxygen or sulfur, by a heterogroup such as N(R7) wherein R7 is H, aryl or C 1 -C 6 alkyl. C 3-10 cycloalkyl or by an arylene group.
  • a C 1-20 alkyl group such as n-butyl may be interrupted by the heterogroup N(RT) as follows: -CH 2 N(R7)CH 2 CH 2 CH 3 , -CH 2 CH 2 N(R7)CH 2 CH 3 , or -CH 2 CH 2 CH 2 N(R7)CH 3 .
  • an alkylene group such as n-butylene may be interrupted by the heterogroup N(RT) as follows: -CH 2 N(R7)CH 2 CH 2 CH 2 -, -CH 2 CH 2 N(R7)CH 2 CH 2 -, or -CH 2 CH 2 CH 2 N(T ⁇ )CH 2 -.
  • the overall charge on a metal complex of formula (I) as defined herein is zero, in which case the complex is neutral and is not associated with a counter-ion.
  • the metal complex of formula (I) may be catonic, and associated with one or more counter- anion(s).
  • the complex may be a monocation or a dication, for example.
  • the counter-anion or -anions may be selected from halide, hexafluorophosphate, chlorate or tetrafluoroborate anions, for example.
  • M is a transition metal or a p- block metal.
  • M is a transition metal
  • M is a p- block metal.
  • transition metal as used herein means any one of the three series of elements arising from the filling of the 3d, 4d and 5d shells, and situated in the periodic table following the alkaline earth metals. This definition is used in N.N. Greenwood and A. Earnshaw “Chemistry of the Elements", First Edition 1984, Pergamon Press Ltd., at page 1060, first paragraph, with respect to the term “transition element”. The same definition is used herein for the term "transition metal”.
  • the term "transition metal”, as used herein, includes for instance Sc, Y, La, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Tc, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd and Hg.
  • M is typically selected from Sc, Y, La, Ti, Zr 5 Hf, V 5 Nb 5 Ta, Cr, Mo 5 W, Mn, Tc, Re, Fe 5 Ru, Os 5 Co, Rh, Ir, Ni, Pd 5 Pt, Cu 5 Ag, Au, Zn, Cd and Hg. More typically, M is a first row transition metal.
  • M is selected from Sc, Ti, V, Cr, Mn 5 Fe, Co, Ni 5 Cu and Zn. Even more typically, M is Ni 5 Cu, Zr, Tc or Zn. Even more typically, M is Ni 5 Cu or Zn.
  • p-block metal as used herein means any metal in the p-block of the periodic table.
  • M is typically selected from Al, Ga, In, Tl, Ge, Sn 5 Pb, Sb 5 Bi and Po. More typically, in this embodiment, M is Ga or In.
  • the present invention provides complexes as defined above wherein M is Cu.
  • Cu herein, is meant a stable isotope or radioisotope of Cu.
  • M may, for instance, be 60 Cu, 61 Cu, 62 Cu, 64 Cu or 67 Cu.
  • the present invention provides complexes as defined above wherein M is Zn.
  • Zn herein, is meant a stable isotope or radioisotope of Zn.
  • M when M is Zn, M may, for instance, be 60 Zn, 61 Zn, 62 Zn, 63 Zn, 65 Zn, 69 Zn, 71 Zn or 72 Zn.
  • the present invention provides complexes as defined above wherein M is Ni.
  • the present invention provides complexes as defined above wherein M is Ga.
  • Ga herein, is meant a stable isotope or radioisotope of Ga.
  • M when M is Ga, M may, for instance, be 65 Ga, 66 Ga, 67 Ga, 68 Ga, 69 Ga, 70 Ga, 71 Ga, 72 Ga, 73 Ga or 74 Ga. In one embodiment, M is 67 Ga.
  • the present invention provides complexes as defined above wherein M is In.
  • In herein, is meant a stable isotope or radioisotope of In.
  • M may, for instance, be 107 In, 108 In, 109 In, 110 In, 111 In, 112 In, 113 In, 114 In, 115 In, 116 In or 117 In.
  • M is 111 In.
  • the present invention provides complexes as defined above wherein M is Zr.
  • Zr herein, is meant a stable isotope or radioisotope of Zr.
  • M when M is Zr, M may, for instance, be Zr, Zr, Zr, Zr, Zr, 89 Zr, 90 Zr, 91 Zr, 92 Zr, 93 Zr, 94 Zr, 95 Zr, 96 Zr or 97 Zr. In one embodiment, M is 89 Zr. In one embodiment the present invention provides complexes as defined above wherein M is Tc. By “Tc”, herein, is meant a stable isotope or radioisotope of Tc. Thus, when M is Tc, M may, for instance, be 99m Tc or 95m Tc. In one embodiment, M is 99m Tc. hi one embodiment M is Ni, Cu, Zn, Ga, In, Zr or Tc.
  • M is Zn, Zr, Ga, In, Tc or Cu.
  • M may be 99m Tc, 111 In, 67 Ga, 89 Zr, 60 Cu, 61 Cu, 62 Cu or 64 Cu.
  • M is Zn, Ga, In, Zr or Cu.
  • M may be 111 In, 67 Ga, 89 Zr, 60 Cu, 61 Cu, 62 Cu or 64 Cu.
  • M is Zn or Cu.
  • M is 60 Cu, 61 Cu, 62 Cu and 64 Cu.
  • M is 64 Cu.
  • an electron donor group is an atom or group which bears either a lone pair of electrons or an overall negative charge. It is, for instance, an O, S or N atom, or an anionic group.
  • the electron donor group is separated by two carbon atoms from the atom to which R5 is attached; this is so that it may adopt the correct position for coordinating to the central metal atom of the complex.
  • the two carbon atoms are connected to each other by a single (saturated) bond, since this allows free rotation and thus further assists with the optimum positioning of the electron donor group.
  • R5 When present, the group R5 is effectively a fifth "pendant" ligand within the complex and its electron donor group becomes part of the metal co-ordination sphere.
  • suitable groups R5 include -CH 2 CO 2 Ro, -CH 2 CO 2 " , -CH 2 CH 2 N(Ro) 2 and -CH 2 CH 2 N “ (R6), wherein R6 is H or alkyl, typically H or methyl, typically H; and a group of formula (FV):
  • ring a is a 5- or 6-membered N-containing heteroaromatic ring which is monocyclic or which is fused to a second aromatic heterocyclic ring or to a benzene ring.
  • An example of a group of formula (IV) is a (pyrid-2-yl)methyl group.
  • R5 may be H, phenyl or Ci-C 6 alkyl.
  • R5 may be H or C 1 -C 6 alkyl.
  • R5 may be H, methyl or ethyl.
  • a is a C 5-10 carbocyclic ring or a C 5-10 heterocyclic ring, which ring is unsubstituted, substituted or part of a fused bi-, tri-, tetra- or polycyclic ring system, wherein the or each further ring of said fused bi-, tri-, tetra- or polycyclic ring system is independently selected from a C 5-10 carbocyclic ring, a C 5-10 heterocyclic ring, a C 5-10 aryl ring and a C 5-10 heteroaryl ring, wherein the ring system is unsubstituted or substituted.
  • a is typically a C 5-6 carbocyclic, C 5-6 heterocyclic, C 5-6 aryl or C 5-6 heteroaryl ring, which ring is unsubstituted, substituted or part of said fused bi-, tri-, tetra- or polycyclic ring system. More typically, a is a C 5-6 carbocyclic ring or a C 5-6 heterocyclic ring, which ring is unsubstituted, substituted or part of said fused bi-, tri-, tetra- or polycyclic ring system.
  • a is a C 5-6 carbocyclic or a C 5-6 aryl ring, which ring is unsubstituted, substituted or part of said fused bi-, tri-, tetra- or polycyclic ring system.
  • a may be a substituted or unsubstituted C 5-6 carbocyclic ring selected from the following groups, which may be unsubstituted (as shown below) or substituted at any one or more available positions in the C 5-6 carbocyclic ring:
  • a may be a methyl substituted C 5 carbocyclic ring, as follows:
  • a is part of a fused bi-, tri- , tetra- or polycyclic ring system, wherein the or each further ring of said fused bi-, tri-, tetra- or polycyclic ring system is independently selected from a C 5-10 carbocyclic ring, a C 5-10 heterocyclic ring, a C 5-10 aryl ring and a C 5-10 heteroaryl ring.
  • the ring system is substituted or unsubstituted. Thus, one or more available positions in the ring system are substituted or unsubstituted. Substituents are typically selected from those listed above for C 1-20 alkyl.
  • the ring system is a fused bi-, tri- or tetracyclic ring system.
  • the ring system is a fused bicyclic ring system.
  • the ring system is typically a group of the following formula, which group may be unsubstituted (as shown below) or substituted at any one or more available positions in the bicyclic ring:
  • the ring system is a fused tricyclic ring system.
  • the ring system is typically selected from groups of the following formulae, which groups may be unsubstituted (as shown below) or substituted at any one or more available positions in the tricyclic ring:
  • the fused tricyclic ring system is selected from the substituted and unsubstituted fused tricyclic ring systems of the diketone compounds of formula (X) below (under the heading "Preparation of complexes employed in the present invention”).
  • the ring system is a fused tetracyclic ring system.
  • the ring system is typically selected from groups of the following formulae, which groups may be unsubstituted (as shown below) or substituted at any one or more available positions in the tricyclic ring:
  • the fused tetracyclic ring system is selected from the substituted and unsubstituted fused tetracyclic ring systems of the diketone compounds of formula (X) below (under the heading "Preparation of complexes employed in the present invention”).
  • the ring system is a fused polycyclic ring system.
  • fused polycyclic ring system means a fused ring system consisting of from 5 to 50 fused rings.
  • fused ring system when a is part of a fused polycyclic ring system, that fused ring system consists of ring a and from 4 to 49 further fused rings, wherein each of said further fused rings is independently selected from a Cs -10 carbocyclic ring, a C 5-10 heterocyclic ring, a C 5-10 aryl ring and a C 5-10 heteroaryl ring.
  • One or more available positions in the polycyclic ring system are substituted or unsubstituted.
  • Substituents are typically selected from those listed above for C 1-20 alkyl.
  • the ring system is typically selected from groups of the following formulae, which groups may be unsubstituted (as shown below) or substituted at any one or more available positions in the polycyclic ring system:
  • the fused polycyclic ring system is selected from the substituted and unsubstituted fused polycyclic ring systems of the diketone compounds of formula (X) below (under the heading "Preparation of complexes employed in the present invention”).
  • a is a C 5-6 carbocyclic ring or C 5-6 aryl ring, more typically a C 5-6 carbocylic ring, which ring is part of said fused tri- or tetracyclic ring system.
  • the ring system is selected from the groups of the following formula (Ha), (lib), (lie) and (Hd):
  • the groups (Ha), (lib), (lie) and (Hd) may be substituted or unsubstituted at any one or more available positions in the ring system.
  • the ring system is selected from the groups of formula (Ha), (lie) and (Hd) above, which groups may be substituted or unsubstituted at any one or more available positions in the ring system. Typically, the groups are unsubstituted.
  • a is a C 5-6 carbocyclic ring or C 5-6 aryl ring, more typically a C 5-6 carbocylic ring, which ring is part of said fused tri- or tetracyclic ring system.
  • the ring system is selected from the groups of the following formula (Ha) 5 (lib) and (lie):
  • the ring system is the group of formula (Ha), which group may be substituted or unsubstituted at any one or more available positions in the ring system.
  • Substituents for the fused ring systems in the complexes of formula (I) as defined herein are typically selected from those listed above for C 1-20 alkyl.
  • the skilled person will understand that the chelating ligand of the complexes of formula (I) as defined herein may exist in more than one resonance form, due to the presence of multiple double bonds in that ligand, particularly within the ring a, between the ring a and the atoms X and X', and within the fused ring systems of which a may be part. Such resonance forms arise from conjugation of those double bonds.
  • the chelating ligand of the complexes of formula (I) as defined herein may exist in more than one tautomeric form.
  • the double bond between the X or X' atom and the ring a may become a single bond if the atom X or X' becomes protonated. This may occur particularly when the X or X' atom in question is N.
  • the source of the proton may, for example, be the complex itself. Alternatively, if the complex is hi solution, for instance, or in contact with another compound, the source of the proton may be the solution in which the complex is dissolved or that other compound with which the complex is in contact.
  • one or both of the double bonds between the ring a and the X and X' atoms may become single bonds through protonation of X and X' respectively. It is to be understood that all of such forms are within the scope of the present invention, and references to any of the complexes of formula (I) as defined herein include all such forms.
  • At least one ring of the fused ring systems in the complexes of formula (I) as defined herein is a C 5-10 aryl ring or a C 5-10 heteroaryl ring. More typically, a is part of said fused tri-, tetra- or polycyclic ring system and at least two rings of said ring system are selected from a C 5-10 aryl ring and a Cs -10 heteroaryl ring.
  • the pi-conjugated aromatic systems of such C 5-10 aryl and C 5-10 heteroaryl rings may contribute to the intrinsic fluorescence of complexes of formula (I) as defined herein. In other words, the ligand backbone may be acting as a fluorophore.
  • the ring system is an unsubstitued group of the formula (Ha). Accordingly, in one embodiment, the invention provides a metal complex of the following formula (Id):
  • the ring system is an unsubstitued group of the formula (lie). Accordingly, in one embodiment, the invention provides a metal complex of the following formula (If):
  • the invention provides a metal complex of the following formula (Ig):
  • n is 0, b is a bond and c is not a bond. Accordingly, in one embodiment the invention provides a metal complex of formula (Ia):
  • n is 1 and either: (i) b is a bond and c is not a bond, or (ii) c is a bond and b is not a bond. Accordingly, in one embodiment, the invention provides a metal complex of formula (Ib):
  • Examples of metal complexes of formula (Ib) are compounds 19 and 20, whose molecular structures were determined by X-ray crystallography (see Examples 19 and 20 below).
  • the X-ray structures of those compounds show that, in each case, M is not bonded to X 5 but instead to N.
  • compounds 19 and 20 b is not a bond and c is a bond.
  • crystal structures of other bis(thiosemicarbazone) complexes having an apical ligand have revealed that in other cases the reverse is true, i.e. c is not a bond and b is a bond.
  • n is 1
  • b is not a bond and c is a bond.
  • the invention provides a metal complex of formula (Ic):
  • M is Zn.
  • a donor group features in the group R5 of the complex of formula (I) as defined above.
  • the complex may also feature one or more further ligands. Additional ligands can be neutral or anionic and can be any suitable small molecule.
  • Typical examples include halogen and water. Hydroxyl is a further example.
  • M represents Zn(II)
  • the d 10 configuration of zinc does not confer stabilisation energy to any particular geometry, and instead the conformation adopted by zinc in its complexes is a function of the steric and conformational demands of the ligands.
  • copper and nickel both of these show a preference for tetradentate planar complexes.
  • the ligand L may be any donor entity.
  • the ligand may be any molecule that comprises an electron donor group.
  • said electron donor group is bonded to M.
  • an electron donor group is an atom or group which bears either a lone pair of electrons, a radical electron, or an overall negative charge.
  • the electron donor group is, for instance, an O, S, N or P atom, an anionic group (e.g. a halide group), or a carbon atom of an organic radical.
  • the electron donor group is an O, S, N or P atom, or L is a halo group, for instance chloro, bromo or iodo. More typically, the electron donor group is an O 5 S, N or P atom, even more typically an O or N atom.
  • L is a halo group. Thus L may be chloro, bromo or iodo. In one embodiment, L is Cl, Br or I. More typically, L is Cl.
  • L may be an unsubstituted or substituted C 5 - I0 heterocyclic ring; an unsubstituted or substituted C 5-10 heteroaryl ring; a C 1-20 hydrocarbon molecule, which hydrocarbon comprises one or more heteroatoms, is unsubstituted or substituted, and is optionally interrupted by N(R7), O, S or arylene, wherein R7 is as defined above; an unsubstituted or substituted organic radical; a macromolecule; a halo group; water; DMSO; or a compound comprising from 2 to 20 unsubstituted or substituted C 5-10 heterocyclic rings, wherein each of said heterocyclic rings is linked to another of said heterocyclic rings by a group A, wherein A is a covalent bond, substituted or unsubstituted arylene, or substituted or unsubstituted C 1-20 alkylene, which compound is either (i) complexed to M", wherein M" is a' transition metal or a main
  • L is a C 5-10 heterocyclic ring. More typically, L is a nitrogen-containing C 5- io heterocyclic ring.
  • L may be l ; 4-diaza-bicyclo[2,2 5 2]octane (also known as DABCO), whose structure is as follows:
  • L may be a compound comprising from 2 to 20 unsubstituted or substituted C 5-1O heterocyclic-rings, wherein each of said heterocyclic rings is linked to another of said heterocyclic rings by a group A, wherein A is a covalent bond, substituted or unsubstituted arylene, or substituted or unsubstituted C 1-20 alkylene, wherein said C 1-20 alkylene is optionally interrupted by by N(R7), O, S or arylene.
  • the electron donor group is an O or N atom, more typically an N atom.
  • Such compounds include porphyrins, porphyrins complexed to M" (wherein M" is a transition metal or a main group metal), bipyridyl compounds and terpyridyl compounds.
  • M is a transition metal or a main group metal
  • bipyridyl compounds An example of a porphyrin which can act as a ligand L is shown below as formula (IVa).
  • An example of a porphyrin complexed to M" is shown below as formula (IVb).
  • Examples of bipyridyl and terpyridyl compounds are given below as formulae (Ilia), (DIb), (HIc) 5 (Did), (Die), (HIf), (Dig), (HIh) and (DH):
  • M" is either a transition metal (as defined above for M) or a main group metal.
  • M" may be an alkali metal, an alkaline earth metal, or a p-block metal.
  • M" may be selected from Li, Na, K, Be, Mg, Ca, Sr, Ba, Al, Ga, In 3 Tl, Ge, Sn, Pb, Sb, Bi, Po.
  • M" is typically Sn, Li, Na, K, Be, Mg or Ca.
  • the complexes of formula (I) are able to interact with cellular nucleic acids, and in particular with DNA, via an interaction between the metal atom M of the complex and a nitrogen atom of the guanosine nucleoside of the nucleic acid. Without wising to be bound by theory, such an interaction could account, at least in part, for the cytotoxicity observed for complexes of formula (I). Other possible mechanisms that could account for cytotoxicity are DNA intercalation or DNA groove binding.
  • the cytotoxicity of the complexes of formula (I) could be modulated, for instance enhanced, if the ligand L of the complex is a molecule which modulates, e.g. enhances, the ability of the complexes to interact with nucleic acids (e.g. DNA).
  • L may be an unsubstituted or substituted C 5-10 heterocyclic or heteroaryl ring which ring is a nitrogenous base.
  • the nitrogenous base is selected from guanine, adenine, cytosine, uracil and thymine, whose structures are shown below.
  • L may be guanine, adenine, cytosine, uracil or thymine.
  • L may be a nucleoside, nucleotide, deoxynucleoside or deoxynucleotide.
  • L may be a macromolecule.
  • the macromolecule comprises a nucleic acid, for instance an oligonucleotide or polynucleotide.
  • L may comprise DNA or RNA.
  • the macromolecule may comprise a peptide (e.g. an oligopeptide or a polypeptide).
  • L may comprise a protein or an enzyme.
  • the electron donor group is typically an O 5 N or S atom of the peptide.
  • L comprises a nucleic acid, a nitrogenous base, a nucleoside, a nucleotide, a deoxynucleoside or a deoxynucleotide
  • the electron donor group is typically a nitrogen atom.
  • the organic radical may be selected from the following groups, for instance, which may be unsubstituted or substituted: C 1-20 alkyl, C 1-10 alkoxy, C 1-10 alkylthio, C 2-20 alkenyl, C 2-20 alkynyl, acyl, acylamido, acyloxy, ester, aryl heteroaryl, C 3-20 heterocyclyl and C 3-20 carbocyclyl.
  • L is selected from a halo group; l,4-diaza-bicyclo[2,2,2]octane; a porphyrin; a porphyrin complexed to M"; a nitrogenous base selected from guanine, adenine, cytosine, uracil and thymine; a nucleoside; a nucleotide; a deoxynucleoside; a deoxynucleotide; an oligonucleotide; a polynucleotide; an oligopeptide; a polypeptide; and a compound of any one of the above formulae (Ilia), (HIb), (IIIc), (Did), (Die), (HIf), (Dig), (DUi), (DH), (IVa) and (IVb).
  • L may be selected from l,4-diaza-bicyclo[2,2,2]octane; a porphyrin; a porphyrin complexed to M"; a nitrogenous base selected from guanine, adenine, cytosine, uracil and thymine; a nucleoside; a nucleotide; a deoxynucleoside; a deoxynucleotide; an oligonucleotide; a polynucleotide; an oligopeptide; a polypeptide; and a compound of any one of the above formulae (Ilia), (DIb), (IIIc), (Did), (Die), (HIf), (Dig), (DIh), (DH), (IVa) and (IVb).
  • X is N.
  • X' is N.
  • X and X' are the same. Thus, typically X and X' are both N. Alternatively, however, X and X' may both be P.
  • Y is S.
  • Y' is S.
  • Y and Y' are the same.
  • Y and Y' may both be S, O 5 N(R5) or P(R5). More typically, both Y and Y' are S.
  • N(R2')-L1 '-Rl ' groups N(R2')-L1 '-Rl ' groups.
  • these groups can be chosen such that the complex has one or more polar groups, for instance sugar moieties, attached.
  • high solubility in non-polar organic solvents can be conferred by selecting these groups to include one or more long chain aliphatic groups, such as a C 6 -C 2O alkyl group.
  • each of the linker groups, Ll 5 Ll ' and L3 can be arranged either way around, ie. head-to-tail or tail- to-head, when linking two groups together.
  • the linking group -alk- S(O) 2 NR 7 - may link the Rl and N groups together in either of the following arrangements: N-alk-S(O) 2 NR 7 -Rl and N-NR 7 S(O) 2 -alk-Rl .
  • Functional substituents such as biologically active molecules and labelled groups, may be conjugated to the metal complexes of formula (I) in such a way as to maximise the potential biomedical use of those complexes.
  • the complex is linked via an exocyclic nitrogen, which may have the advantage of causing minimum perturbation in any potential hypoxic selectivity of the molecules.
  • neither or only one of Rl and Rl ' features a Z group. In one embodiment, neither Rl nor Rl' features a Z group. In another embodiment, one of Rl and Rl' features a Z group.
  • Rl or Rl' is selected from Z, L3-Z, L3-alk-Z, and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, amino, C 1-10 alkylamino, di(C 1 _ 1 o)alkylamino, C3.20 carbocyclyl, C 3-20 heterocyclyl, C 3-20 heteroaryl, aryl, aryloxy, -alk-C 3-20 carbocyclyl, -alk-C 3-20 heterocyclyl, -3Ik-C 3-20 heteroaryl, and -alk-aryl, which group is further substituted by L3-Z or L3-alk-Z, wherein L3 is as defined above for Ll and Ll', and wherein said C 1-20 alkyl, C 2-20 alkenyl and C 2-20 alkynyl are optionally interrupted by N(R7), O, S or
  • this group may be any group, part or all of which can be excited by radiation to fluorescence.
  • the fluorophore is a zinc bis(thiosemicarbazone) complex
  • the fluorophore is a 2-(4- aminophenyl)benzothiazole or derivative thereof. Examples of such suitable derivatives include those in the table below.
  • Complexes of formula (III) which incorporate a fluorphore Z may be synthesised by reaction of a fluorophore containing an aldehyde, ketone, carboxylic acid or acid halide fluorophore with a precursor complex containing an amino group.
  • the precursor complex may be a complex of formula (I) in which Rl or Rl ' contains an amino group, for example a complex of formula (I) in which Rl or Rl ' is an amino group.
  • the fluorophore for reaction with the amino group may be, for instance, benzaldehyde, 2-furaldehyde, salicyladehyde, hydroxynaphthaldehyde, 4-(di-n-propylamino) benzaldehyde, butane-2-3-dione, phenyl glyoxal, terephthalaldehyde, glyoxal, isophthaldehyde, pyruric acid, propionaldehyde, 4- fluorobenzaldehyde, 2-pyridinecarboxaldehyde, or a suitable zinc bis(thiosemicarbazone) complex, which may be a zinc bis(thiosemicarbazone) complex of formula (I) or
  • fluorophore Z may be derived from any of the compounds in the preceding list.
  • the label can be any moiety that permits the detection of the complex.
  • the label may be a fluorophore, for instance as described above. Typically it is a radioisotope. Examples include 18 F, 11 C, 14 C 5 3 H, 99m Tc, 111 In, 123 I and 188 Re. In another embodiment it may be a stable isotope. Examples include 13 C, 2 H and 15 N.
  • it is a label that decays via positron emission, beta emission, electron capture or Auger emissions. More typically, the label decays by positron emission. Most typically the label is 18 F.
  • 18 F is typically prepared from a cyclotron in the form OfKH 18 F 2 and the 18 F in KH 18 F 2 replaces a suitable leaving group in the complex with 18 F.
  • suitable leaving groups include imidazosulfonyl, triflate, mesylate and tosylate. Accordingly, in a preferred embodiment of the present invention, the group Z in the complexes of formula (I) as defined above may represent such a suitable leaving group. Images may be acquired from about 5 minutes after administration until about 8 hours after administration.
  • the maximum period in which images may be acquired is determined by 3 factors: the physical half-life of 18 F (110 minutes); the sensitivity of the detectors and the size of the dose administered. Those of skill in the art can adjust these factors to permit the acquisition of images at an appropriate time. Details of imaging procedures are well known. Radionuclides which emit gamma radiation can be used for SPECT imaging. SPECT scanners are gamma cameras which detect the photons produced from this decay. Facilities for SPECT imaging are widely available in hospitals. Radionuclides suitable for PET imaging must undergo ⁇ + decay, in which the nucleus emits a positron and neutrino. When the positron encounters an electron the two annihilate and two gamma rays are emitted.
  • the present invention provide diagnostic agents comprising a complex of formula (I) as defined above, for use in SPECT imaging.
  • Z is a cytotoxin it is, for instance, an agent which is cytotoxic to cancer cells.
  • cytotoxins include taxanes such as taxol and taxotere; Vinca alkaloids such as vincristine and vinblastine; anthracycline antibiotics such as daunorubicin, epirubicin and doxorubicin; epipodophyllotoxins such as etoposide and plicamycin; mitoxantrone; and actinomycin D.
  • BAM Z may be a biologically active molecule ("BAM”), which shows specific in vivo targeting to a diseased tissue of interest.
  • BAM' s for instance monoclonal antibodies, antibody fragments and peptides, have been investigated in medical imaging.
  • 111 In- DTPA-B72.3(OnoScint) and 99m Tc-IMMU-4 (CEO-SCAN) both use antibody binding and are approved for clinical use in the US.
  • octreotide labelled with 111 In using DTPA is a diagnostic imaging agent for neuroendocrine tumors. That agent uses binding of the cyclic peptide octreotide (shown below) to peptide based tumor receptors that interact with the hormone somatostatin.
  • Ga and In complexes linked to folic acid via DTPA chelation have also shown promising results in tumor imaging.
  • the structures of octreotide, DTPA and folic acid are shown below:
  • Z may be a biologically active molecule, wherein the biologically active molecule is selected from a monoclonal antibody, an antibody fragment, a peptide, octreotide and folic acid.
  • Z may be an amino acid, a peptide, an oligopeptide or a polypeptide.
  • any amino acid or combination of amino acids may be used.
  • Z may be any amino acid, derivative thereof or combinations (in the form of a straight or branched chain) thereof. Examples include -Lys(Boc)-OH, - Orn(Boc)-OH, -Lys-OH and -octreotide.
  • Z may be -ONSu, derived from N- hydroxysuccinimide.
  • Z When Z is a sugar moiety, it can be a monosaccharide, disaccharide or trisaccharide. It can, for example, be glucose, sucrose or lactose.
  • Z is a bis(thiosemicarbazone) or thiosemicarbazone complex
  • Z of the complex of formula (I) is a Cu or Zn complex of a bis(thiosemicarbazone) or of a thiosemicarbazone, thereby creating a dimer wherein two complexes are linked by -Ll-Rl-Ll-, -Ll-alk-Rl-Ll-, -Ll-Rl-alk-Ll- or -Ll- alk-Rl-alk-Ll- wherein Ll and Rl are as defined above.
  • the complex is a bis(thiosemicarbazone) Cu or Zn complex. More typically it is a Zn complex.
  • the group Z is only present in one of Rl and Rl ' .
  • both of the metal atoms present are typically Zn, thus creating a bi-nuclear zinc complex. Linking two zinc centres in this way may have a significant effect on the fluorescence properties as compared to the properties of a mono-nuclear zinc complex.
  • the present invention provides complexes of formula (I) as defined above, wherein M is a copper radionuclide and Z represents a zinc bis(thiosemicarbazone) complex (for instance, a zinc bis(thiosemicarbazone) complex of formula (I)), thus providing a radiopharmaceutical copper complex tethered to a more fluorescent zinc complex.
  • the invention provides a complex of the following formula (Ie):
  • each M which is the same as or different from the other M, is a transition metal; a, R2, R2' and Ll are as defined above for formula (I);
  • Q is -Ll- or -L1-R1-L3- wherein Ll and L3 are as defined above for formula (I);
  • Rl is selected from hydrogen, and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, amino, C 1-10 alkylamino, di(C 1 . 10 )alkylamino, C 3-20 carbocyclyl, C 3-20 heterocyclyl, C 3-20 heteroaryl, aryl, aryloxy, -alk-C3 -20 carbocyclyl, -alk-C 3- 20 heterocyclyl, -alk-C 3-20 heteroaryl, and -alk-aryl, wherein said C 1-20 alkyl, C 2-20 alkenyl and C 2-20 alkynyl are optionally interrupted by N(R7), O, S or arylene.
  • neither Rl nor Rl ' features a Z group.
  • Rl and Rl' which are the same or different, are each independently selected from hydrogen, and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2 . 2 o alkenyl. C 2-20 alkynyl, amino, C 1-10 alkylamino, di(C 1-10 )alkylamino 5 C 3-2O carbocyclyl, C 3-20 heterocyclyl, C 3-20 heteroaryl, aryl, aryloxy, -alk-C 3-20 carbocyclyl, -alk-C 3-20 heterocyclyl, - alk-C 3-2 o heteroaryl, and -alk-aryl, wherein said C 1-20 alkyl, C 2-20 alkenyl and C 2-20 alkynyl are optionally interrupted by N(R7), O, S or arylene.
  • Rl and Rl' which are the same or different, are each independently selected from hydrogen, substituted or unsubstituted C 1-2O alkyl, substituted or unsubstituted aryl and substituted or unsubstituted C 2-20 alkenyl. Even more typically, Rl and Rl ' are each independently selected from hydrogen, unsubstituted C 1-20 alkyl, unsubstituted aryl and unsubstituted C 2-20 alkenyl. Even more typically, Rl and Rl ' are each independently selected from H 5 unsubstituted C 1-6 alkyl, phenyl and allyl. Typically, Rl and Rl ' are the same.
  • R2 and R2' which are the same or different, are each independently selected from hydrogen, substituted or unsubstituted C 1-20 alkyl, substituted or unsubstituted aryl and substituted or unsubstituted C 2-20 alkenyl. More typically, R2 and R2' are independently selected from H 5 substituted or unsubstituted C 1-6 alkyl and substituted or unsubstituted phenyl. Usually, R2 and R2' are the same. Thus, usually R2 and R2' are both either H substituted or unsubstituted C 1-6 alkyl or substituted or unsubstituted phenyl. More typically, R2 and R2' are both H.
  • Ll, Rl and R2 may form, together with the N atom to which Ll and R2 are attached, an unsubstituted or substituted C 3-20 heterocyclyl group (typically a C 5-7 heterocyclyl group) or an unsubstituted or substituted C 3-20 heteroaryl group (typically a C 5-7 heteroaryl group); and Ll', Rl' and R2' may form, together with the N atom to which Ll ' and R2' are attached, an unsubstituted or substituted C 3-20 heterocyclyl group (typically a C 5-7 heterocyclyl group) or an unsubstituted or substituted C 3-20 heteroaryl group (typically a C 5-7 heteroaryl group).
  • Ll, Rl and R2 may form, together with the N atom to which Ll and R2 are attached, a group of any of the following formulae (Ilia), (HIc) and (IIIc):
  • Ll', Rl' and R2' may form, together with the N atom to which Ll ' and R2' are attached a group of any of formulae (Ilia), (IIIc) and (IIIc).
  • Ll is a covalent bond.
  • Ll ' is a covalent bond.
  • Rl and Rl' which are the same or different, are each independently selected from hydrogen, and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2- 20 alkynyl, amino, C 1-10 alkylamino, di(C 1-10 )alkylamino, C 3-20 carbocyclyl, C 3-20 heterocyclyl, C 3-2 O heteroaryl, aryl, aryloxy, -alk-C 3-20 carbocyclyl, -alk-C 3-20 heterocyclyl, -alk-C 3 .
  • C 1-20 alkyl, C 2-20 alkenyl and C 2-20 alkynyl are optionally interrupted by N(R7), O, S or arylene; and R2 and R2 ⁇ which are the same or different, are each independently selected from H, substituted or unsubstituted C 1-6 alkyl and substituted or unsubstituted phenyl; provided that Ll, Rl and R2 may form, together with the N atom to which Ll and R2 are attached, an unsubstituted or substituted C 5-7 heterocyclyl group or an unsubstituted or substituted C 5 .
  • Ll', Rl' and R2' may form, together with the N atom to which Ll ' and R2' are attached, an unsubstituted or substituted C 5-7 heterocyclyl group or an unsubstituted or substituted C 5-7 heteroaryl group.
  • R7 is H or C 1-6 alkyl or phenyl. More typically R7 is H.
  • the present invention provides a metal complex of formula (I):
  • M is a transition metal; either (i) n is 0, b is a bond and c is not a bond; (ii) n is 1 , b is not a bond and c is a bond; or (iii) n is 1 , b is a bond and c is not a bond;
  • L is a ligand comprising an electron donor group
  • a is a C 5-I0 carbocyclic, C 5-I0 heterocyclic, C 5-10 aryl or C 5-10 heteroaryl ring, which ring is unsubstituted, substituted or part of a fused bi-, tri-, terra- or polycyclic ring system, wherein the or each further ring of said fused bi-, tri-, tetra- or polycyclic ring system is independently selected from a C 5-10 carbocyclic ring, a C 5-10 heterocyclic ring, a C 5-10 aryl ring and a C 5-10 heteroaryl ring, wherein the ring system is unsubstituted or substituted;
  • X and X' which are the same or different, are independently selected from N and P; Y and Y', which are the same or different, are independently selected from S, O,
  • each R5 is independently selected from H, C 1 -C 6 alkyl and a group comprising an electron donor group, which donor group is separated by two carbon atoms from the N or P atom to which R5 is attached;
  • Ll and Ll' which are the same or different, are each independently selected from a covalent bond and a linker group selected from -alk-, -C(O)-, -alk-C(O)-, -C(O)O-,-alk- C(O)O-, -OC(O)-, -alk-OC(O)-, -0-, -alk-O-, -N(R7>, -alk-N(R7)-, -N(R7)C(0), -alk- N(R7)C(O>, -C(O)N(R7), -alk-C(0)N(R7), -C(S)-, -alk-C(S)-, -S-, -alk-S-, -C(S)N(R7)-, - alk-C(S)N(R7)-, -N(R7)C(S)-, -alk-N(R7)-,
  • Z is a moiety selected from a biologically active molecule, a fluorophore, a cytotoxin, an amino acid, a peptide, an oligopeptide, a polypeptide, a sugar, a group containing a label, a leaving group which is replaceable by a group containing a label, and a complex of a transition metal with a bis(thiosemicarbazone) or a thiosemicarbazone;
  • R2 and R2' which are the same or different, are each independently selected from H and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, amino, C 1-10 alkylamino, di(C 1-10 )alkylamino, C 3-20 carbocyclyl, C 3-20 heterocyclyl, C 3-20 heteroaryl, aryl, aryloxy, -alk-C 3-20 carbocyclyl, -alk-C 3-20 heterocyclyl, -alk-C 3 . 20 heteroaryl, and -alk-aryl, which C 1-20 alkyl, C 2 . 20 alkenyl and C 2-20 alkynyl are optionally interrupted by N(R7), O, S or arylene;
  • -alk- is unsubstituted or substituted C 1-20 alkylene which is optionally interrupted by N(R7), O, S or arylene;
  • R7 is H, C 1-6 alkyl, C 3-10 cycloalkyl or aryl; provided that Ll, Rl and R2 may form, together with the N atom to which Ll and R2 are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; and provided that Ll', Rl ' and R2' may form, together with the N atom to which Ll ' and R2' are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group.
  • the metal complexes of the invention are taken up into a range of human cancer cell lines, and exhibit significant cytotoxicity towards those cell lines.
  • the complexes of the invention are candidates for use as therapeutic agents, in particular for use in treating cancers and other conditions characterised by undesirable cellular proliferation.
  • complexes of the invention have the potential to be hypoxic selective, as described hereinbelow, and may therefore be suitable for therapy and/or imaging of hypoxic tumours. Additionally, or as an alternative to hypoxic selectivity, complexes of the invention may be conjugated to a biologically active molecule which serves to target the complex to the desired site in vivo.
  • the invention further provides:
  • composition comprising a complex of the invention as defined above and a pharmaceutically acceptable carrier.
  • a complex of the invention as defined above for use in a method of medical treatment.
  • a complex of the invention as defined above in the manufacture of a medicament for use in the treatment of a condition characterised by undesirable cellular proliferation.
  • a method of treating a condition characterised by undesirable cellular proliferation which method comprises administering to a patient in need of such treatment an effective amount of a complex of the invention as defined above.
  • compositions for use in treating a condition characterised by undesirable cellular proliferation comprising a pharmaceutically acceptable carrier or diluent and a complex of the invention as defined above.
  • complexes of the invention including copper complexes
  • complexes of the invention have enhanced fluorescence compared with known metal thiosemicarbazone compounds, and that the complexes possess intrinsic fluorescence.
  • the fluorescent properties of the complexes allows the distribution of the complexes within cells to be monitored.
  • complexes of the invention may be radiolabelled with metastable metal radionuclides which are useful in medical imaging techniques such as PET (Positron Emission Tomography) and SPECT (Single Photon Emmission Computerised Tomography).
  • PET Positron Emission Tomography
  • SPECT Single Photon Emmission Computerised Tomography
  • the complexes of the invention are candidates for use as imaging agents, using either a radioactive imaging technique such as PET and SPECT, or a non-radioactive optical technique, such as fluorescence.
  • the radiolabelled complexes may be suitable for both non- radioactive and radioactive imaging, which may be used in combination.
  • radioactive imaging techniques such as PET and SPECT could provide an extremely powerful tool in the clinical diagnosis and treatment of disease.
  • the complexes of the invention are candidates for use as dual therapy and imaging agents, for example in the treatment and imaging of cancer tumours and other conditions characterised by undesirable cellular proliferation.
  • the present invention further provides: a diagnostic agent or medical imaging agent which comprises a complex of the invention as defined above.
  • a diagnostic agent or medical imaging agent which comprises a complex of the invention as defined above.
  • a method of imaging a cell or in vitro biopsy sample which method comprises: (a) contacting the cell or in vitro biopsy sample with a complex of the invention as defined above; and (b) imaging the cell or in vitro biopsy sample.
  • a method of imaging a patient in need thereof which method comprises: (a) administering to the patient a complex of the invention as defined above; and (b) imaging the patient.
  • the metal complexes of formula (Ia) can be prepared by a templating reaction in the presence of a salt of the metal M, in which the ligand is formed in situ around the metal centre M from ligand precursor compounds.
  • the metal M acts as a templating agent.
  • the invention provides a process for producing a metal complex of formula (Ia):
  • M is a transition metal or a p-block metal
  • a is a C 5-10 carbocyclic, C 5-10 heterocyclic, C 5-10 aryl or C 5-10 heteroaryl ring, which ring is unsubstituted, substituted or part of a fused bi-, tri-, tetra- or polycyclic ring system, wherein the or each further ring of said fused bi-, tri-, tetra- or polycyclic ring system is independently selected from a C 5-10 carbocyclic ring, a C 5-10 heterocyclic ring, a C 5-10 aryl ring and a Cs -10 heteroaryl ring, wherein the ring system is unsubstituted or substituted;
  • X and X' which are the same or different, are independently selected from N and P;
  • Y and Y' which are the same or different, are independently selected from S, O, N(R5) and P(R5), wherein each R5 is independently selected from H, C 1 -C 6 alkyl, phenyl and a group comprising an electron donor group, which donor group is separated by two carbon atoms from the N or P atom to which R5 is attached;
  • Ll and Ll' which are the same or different, are each independently selected from a covalent bond and a linker group selected from -alk-, -C(O)-, -alk-C(O)-, -C(O)O-,-alk- C(O)O-, -OC(O)-, -alk-OC(O)-, -O-, -alk-O-, -N(R7)-, -alk-N(R7)-, -N(R7)C(0), -alk- N(RT)C(O)-, -C(O)N(RT
  • Z is a moiety selected from a biologically active molecule,, a fluorophore, a cytotoxin, an amino acid, a peptide, an oligopeptide, a polypeptide, a sugar, a group containing a label, a leaving group which is replaceable by a group containing a label, and a complex of a transition metal with a bis(thiosemicarbazone) or a thiosemicarbazone;
  • R2 and R2' s which are the same or different, are each independently selected from H and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, amino, C 1-10 alkylamino, di(C 1-10 )alkylamino, C 3-20 carbocyclyl, C 3-20 heterocyclyl, C 3-20 heteroaryl, aryl, aryloxy, -alk-C 3-20 carbocyclyl, -alk-C 3-20 heterocyclyl, -alk-C 3 - 20 heteroaryl, and -alk-aryl, which C 1-20 alkyl, C 2-20 alkenyl and C 2-20 alkynyl are optionally interrupted by N(RT), O, S or arylene;
  • -alk- is unsubstituted or substituted C 1-20 alkylene which is optionally interrupted by N(RT), O, S or arylene; and R7 is H, C 1-6 alkyl, C 3-10 cycloalkyl or aryl; provided that Ll, Rl and R2 may form, together with the N atom to which Ll and R2 are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; and provided that Ll ', Rl' and R2' may form, together with the N atom to which Ll ' and R2' are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; which process comprises treating, in the presence of a solvent, a salt of M with either: (i) a compound of following formula (X), a compound of the following formula (Y) and a compound of
  • the solvent is a polar solvent, more typically a polar protic solvent.
  • the solvent is acetic acid, DMSO or an alcohol such as methanol or ethanol. More typically, the solvent is acetic acid.
  • the reaction is carried out with heating. More typically the reaction is carried out with heating to the reflux temperature of the solvent used. For example, when the solvent is acetic acid the reaction may be carried out at a temperature of 118 °C or higher, e.g. at a temperature of 120 0 C. Typically, heating is carried out for about 2 hours or longer.
  • any suitable salt of M may be employed.
  • An example of a suitable salt of M is an acetate salt of M.
  • the salt is typically M(O Ac) 2 .xH 2 0.
  • x is from 1 to 4.
  • x is 1 for Cu, 2 for Zn and 4 for Ni.
  • the salt of M is present in a molar excess with respect to the compound of formula (X) or the compound of formula (V), as the case may be. More typically, the salt of M is present in about a twofold or about a threefold molar excess with respect to (X) or (V).
  • M is Zn
  • the salt of Zn is typically present in about a threefold molar excess with respect to (X) or (V).
  • M is Ni
  • the salt of Ni is typically present in about a twofold molar excess with respect to (X) or (V).
  • a catalytic amount of trifluoroacetic acid is present in the reaction mixture.
  • TFA trifluoroacetic acid
  • 0.1 to 1 ml TFA is present. More typically, 0.2 to 0.8 ml, for instance about 0.5 ml of TFA is present.
  • the presence of TFA has been found in one case to result in a product (i.e. a metal complex of formula Ia) of increased purity.
  • the presence of TFA has also been found to greatly reduce the reaction time.
  • the presence of TFA both reduced the reaction time and increased the purity of the product.
  • M is Ni or Zn.
  • the process for producing a metal complex of formula (Ia) comprises treating, in the presence of a solvent, a salt of M with a compound of following formula (X), a compound of the following formula (Y) and a compound of the following formula (Z):
  • that compound of formulae (Y) and (Z) is present in a molar excess, typically about a fourfold molar excess, with respect to the compound of formula (X).
  • the process for producing a metal complex of formula (Ia) comprises treating, in the presence of a solvent, a salt of M with a compound of the following formula (V) and a compound of the following formula (Z):
  • the solvent is a polar solvent, more typically a polar protic solvent.
  • the solvent is an alcohol, such as methanol or ethanol. More typically-, the solvent is ethanol.
  • the reaction is carried out with heating, typically at the reflux temperature of the solvent used.
  • the solvent is ethanol the reaction is suitably carried out at a temperature of 78 0 C or higher, e.g. at a temperature of 80 °C.
  • heating is carried out for about 1 hour or longer. More typically, heating is carried out for about 2 hours or longer, for instance for about 2 hours.
  • Comparative Examples 1, 3, 5 and 7 are examples of preparations of compounds of formula (V).
  • metal complexes of formula (Ia) may be prepared by transmetallation. Accordingly, the invention further provides a process for producing a metal complex of the following formula (Ia) by transmetallation: wherein:
  • M is a transition metal or a p-block metal
  • a is a C 5-10 carbocyclic, C 5-10 heterocyclic, C 5-10 aryl or C 5-10 heteroaryl ring, which ring is unsubstituted, substituted or part of a fused bi-, tri-, terra- or polycyclic ring system, wherein the or each further ring of said fused M-, tri-, tetra- or polycyclic ring system is independently selected from a C 5-10 carbocyclic ring, a C 5-10 heterocyclic ring, a C 5-10 aryl ring and a C 5-1O heteroaryl ring, wherein the ring system is unsubstituted or substituted;
  • X and X' which are the same or different, are independently selected from N and P; Y and Y', which are the same or different, are independently selected from S, O,
  • each R5 is independently selected from H, C 1 -C 6 alkyl, phenyl and a group comprising an electron donor group, which donor group is separated by two carbon atoms from the N or P atom to which R5 is attached;
  • Ll and LV which are the same or different, are each independently selected from a covalent bond and a linker group selected from -alk-, -C(O)-, -alk-C(O)-, -C(O)O-,-alk- C(O)O-, -OC(O)-, -alk-OC(O)-, -0-, -alk-O-, -N(R7)-, -alk-N(R7)-, -N(R7)C(O), -alk- N(R7)C(O)-, -C(O)N(R7), -alk-C(O)N(R7), -alk-C(O)N(R7), -C(S)-, -alk-C(S)-, -S-, -alk-S-, -C(S)N(R7)-, - alk-C(S)N(R7)-, -N(R7)
  • Rl and Rl ' which are the same or different, are each independently selected from hydrogen, Z, L3-Z, L3-alk-Z, and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2- I 0 alkenyl, C 2-20 alkynyl, amino, C 1-10 alkylamino, di ⁇ i-i ⁇ alkylamino, C 3 .
  • Z is a moiety selected from a biologically active molecule, a fluorophore, a cytotoxin, an amino acid, a peptide, an oligopeptide, a polypeptide, a sugar, a group containing a label, a leaving group which is replaceable by a group containing a label, and a complex of a transition metal with a bis(thiosemicarbazone) or a thiosemicarbazone;
  • R2 and R2' which are the same or different, are each independently selected from H and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2 -2 0 alkenyl, C 2-20 alkynyl, amino, C 1-10 alkylamino, di(C 1-10 )alkylamino, C 3-20 carbocyclyl, C 3-20 heterocyclyl, C 3-20 heteroaryl, aryl, aryloxy, -alk-C 3-20 carbocyclyl, -alk-C 3-20 heterocyclyl, -alk-C 3-20 heteroaryl, and -alk-aryl, which C 1-20 alkyl, C 2-20 alkenyl and C 2-20 alkynyl are optionally interrupted by N(RT), O, S or arylene;
  • -alk- is unsubstituted or substituted C 1-20 alkylene which is optionally interrupted by N(RT), O, S or arylene; and R7 is H, C 1-6 alkyl, C 3-10 cycloalkyl or aryl; provided that Ll, Rl and R2 may form, together with the N atom to which Ll and R2 are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; and provided that Ll ', Rl' and R2' may form, together with the N atom to which Ll ' and R2' are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; which process comprises treating a salt of M, in the presence of a solvent, with a metal complex of the following formula (W):
  • M' is a metal other than M and is either (i) a transition metal or (ii) a main group metal; and a, X', X, Y', Y 5 R2, R2 ⁇ Rl, Rl', Ll and Ll' are as defined above for the metal complex of formula (Ia).
  • Any suitable solvent may be employed.
  • the solvent is a polar solvent.
  • the solvent is DMSO or an alcohol such as methanol or ethanol. More typically, the solvent is methanol. Usually, no heating is required and the reaction is conducted at room temperature.
  • thermodynamic stabilities of corresponding complexes of bivalent ions of the first transition series usually vary in accordance with the Irving- Williams series: Mn(II) ⁇ Fe (II) ⁇ Co(II) ⁇ Ni(II) ⁇ Cu(II) > Zn(II).
  • Chelating and macrocyclic ligands can form a cavity which can be used to select one ion over another based on size. In general, however, copper complexes are expected to be more stable than analogous zinc complexes or analogous nickel complexes.
  • Examples 15 and 16 describe the synthesis of copper ⁇ zXthiosemicarbazone) complexes of the invention from the corresponding zinc ⁇ (thiosemicarbazone) complexes, and Example 27 describes the synthesis of a radiolabeled 64 Cu &w(thiosemicarbazone) complex of the invention by 64 Cu transmetallation of the corresponding zinc complex.
  • M is Cu, Ni or Zn. More typically, M is Cu. In one embodiment, M is Cu, which Cu is a radionuclide. More typically, it is a positron emitter such as 64 Cu. When M is Cu, typically M' is Ni or Zn.
  • M' is a main group metal.
  • M' may be an alkali metal, an alkaline earth metal, or a p-block metal.
  • M' may be selected from Li, Na, K, Be, Mg, Ca, Sr, Ba, Al, Ga, In, Tl, Ge, Sn, Pb, Sb, Bi, Po.
  • M' is Sn, Li, Na, K, Be, Mg or Ca. More typically, M' is Sn.
  • Any suitable salt of M may be employed.
  • An example of a suitable salt of M is an acetate salt of M.
  • M is Cu 5 Zn or Ni
  • the salt is typically M(OAc) 2 .xH 2 O.
  • x is from 1 to 4.
  • x is 1 for Cu, 2 for Zn and 4 for Ni.
  • the salt of M is present in a molar excess with respect to the compound of formula (W). More typically, the salt of M is present in about a twofold molar excess with respect to (W).
  • Metal complexes of formula (Ia) may be further derivatised to produce metal complexes of formula (Ib).
  • the invention provides a process for producing a metal complex of the following formula (Ib):
  • M is a transition metal or a p-block metal; either (i) b is a bond and c is not a bond, or (ii) c is a bond and b is not a bond;
  • L is a ligand comprising an electron donor group
  • a is a C 5-10 carbocyclic, C 5 .10 heterocyclic, C 5-10 aryl or C 5 ⁇ o heteroaryl ring, which ring is unsubstituted, substituted or part of a fused bi-, tri- 5 tetra- or polycyclic ring system, wherein the or each further ring of said fused bi-, tri-, tetra- or polycyclic ring system is independently selected from a C 5-10 carbocyclic ring, a C 5-10 heterocyclic ring, a C 5-1O aryl ring and a C 5-10 heteroaryl ring, wherein the ring system is unsubstituted or substituted;
  • X and X' which are the same or different, are independently selected from N and P;
  • Y and Y' which are the same or different, are independently selected from S, O, N(R5) and P(R5), wherein each R5 is independently selected from H, C 1 -C 6 alkyl, phenyl and a group comprising an electron donor group, which donor group is separated by two carbon atoms from the N or P atom to which R5 is attached;
  • Ll and Ll' which are the same or different, are each independently selected from a covalent bond and a linker group selected from -alk-, -C(O)-, -alk-C(O)-, -C(O)O-,-alk- C(O)O-, -OC(O)-, -alk-OC(O)-, -0-, -alk-O-, -N(R7)-, -alk-N(R7)-, -N(RT)C(O), -alk- N(RT)C(O)-, -C(O)N(RT
  • Z is a moiety selected from a biologically active molecule, a fluorophore, a cytotoxin, an amino acid, a peptide, an oligopeptide, a polypeptide, a sugar, a group containing a label, a leaving group which is replaceable by a group containing a label, and a complex of a transition metal with a bis(thiosemicarbazone) or a thiosemicarbazone;
  • R2 and R2' which are the same or different, are each independently selected from H and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2-2O alkynyl, amino, C 1-10 alkylamino, di(C 1-1 o)alkylamino, C 3-20 carbocyclyl, C 3-2O heterocyclyl, C 3 . 2 o heteroaryl, aryl, aryloxy, -alk-C 3 .
  • -alk- is unsubstituted or substituted C 1-20 alkylene which is optionally interrupted by N(RT), O, S or arylene;
  • R7 is H, C 1-6 alkyl, C 3-10 cycloalkyl or aryl; provided that Ll, Rl and R2 may form, together with the N atom to which Ll and R2 are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; and provided that Ll ', Rl' and R2' may form, together with the N atom to which Ll ' and R2' are attached, an unsubstituted or substituted C 3-2 o heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; the process comprising treating a compound of formula (Ia) as defined above, with either:
  • a precursor compound comprising L in the presence of a solvent, wherein L is said ligand comprising an electron donor group.
  • the electron donor group of L is a heteroatom which bears a lone pair of electrons
  • the compound of formula (Ia) is generally treated with L itself, rather than with a precursor compound that comprises L.
  • Such heteroatoms are generally able to coordinate to metal centres as well as exist in a free, unbound state.
  • L is DABCO (in which the electron donor group is a nitrogen atom bearing a lone pair of electrons)
  • the compound of formula (Ia) is treated with DABCO itself, rather than with another compound that comprises DABCO.
  • the compound of formula (Ia) is generally treated with L itself, rather than with a precursor of L: in those cases, the electron donor group is typically a heteroatom of L, which heteroatom bears a lone electron pair and can interact with the metal centre as well as exist in an unbound state.
  • said treatment of the compound of formula (Ia) is with L, wherein L is said ligand comprising an electron donor group.
  • the solvent is any suitable solvent.
  • the solvent is a polar aprotic solvent, for instance THF or diethyl ether, or a non- polar organic solvent, for instance pentane or hexane.
  • L is present in a molar excess with respect to the compound of formula
  • L may be present in a tenfold or greater molar excess with respect to the compound of formula (Ia).
  • the reaction does not require heating and is carried out at room temperature.
  • said treatment of the compound of formula (Ia) with L is by co- crystallisation of (Ia) and L from a solution of (Ia) and L.
  • the solvent is a polar aprotic solvent, such as THF or diethyl ether, layered with a non-polar organic solvent, such as pentane or hexane.
  • the electron donor group of L is an atom or group which bears an overall negative charge, or a radical electron
  • the compound of formula (Ia) is generally treated with a precursor compound comprising L.
  • the precursor compound comprising L may be a salt of L with an appropriate cation, or an adduct of L with another group, such as a leaving group.
  • L is an organic radical, such as C 1-2O alkyl, C 1-10 alkoxy, C 1-10 alkylthio,
  • the compound of formula (Ia) may be treated with a salt of L.
  • the salt of L may be an alkali metal salt, such as a lithium salt or sodium salt.
  • the metal complex employed in the present invention may incorporate a group Z, i.e. a biologically active molecule, a fluorophore, a cytotoxin, an amino acid, a peptide, an oligopeptide, a polypeptide, a sugar, a group containing a label, a leaving group which is replaceable by a group containing a label, or a complex of a transition metal with a bis(thiosemicarbazone) or a thiosemicarbazone.
  • a group Z i.e. a biologically active molecule, a fluorophore, a cytotoxin, an amino acid, a peptide, an oligopeptide, a polypeptide, a sugar, a group containing a label, a leaving group which is replaceable by a group containing a label, or a complex of a transition metal with a bis(thiosemicarbazone) or a thiosemicarbazone
  • such a group Z may be incorporated into a metal complex employed in the present invention by synthesising that complex according to the process of the present invention using a ligand precursor compound, of formula (Y), (Z) or (V) above, whose Rl or Rl ' group already contains that group Z.
  • the group Z may be incorporated by coupling a "precursor" metal complex of formula (I) to that group Z.
  • a "precursor" metal complex of formula (I) may comprise a terminal carboxylic acid group (e.g. within a terminal benzoic acid group) which carboxylic acid group can be used to couple the precursor complex to a group Z.
  • carboxylic acid group of the precursor complex can be readily converted into an activated ester, which is susceptible to nucleophilic attack by amines and hydrazines.
  • a metal complex of formula (I) can be formed which is different from the precursor complex of formula (I) and which comprises the group Z.
  • the group -Z, or the group -L3-Z- or the group -L3-alk-Z is coupled to a precursor metal complex of formula (I), or alternatively incorporated in a ligand precursor compound of formula (Y), (Z) or (V), using conventional techniques known to the person of skill in the art.
  • Z may be coupled to a thiosemicarbazone derivative via one or more peptide bonds, typically one peptide bond.
  • this link is formed in a reaction between a -COO(R7) group and a -NH(R7) group in the thiosemicarbazone derivative and the group containing Z, respectively, or vice versa.
  • Z may be coupled to the terminal -NH 2 group of the thiosemicarbazone derivative (10a) via one or more irnine links, typically one imine link.
  • irnine links typically one imine link.
  • the dione (1 Ia) is typically symmetrical and nucleophilic attack on the dione takes place at both carbonyl groups, giving rise to a thiosemicarbazone derivative (13a) which is symmetrical about L". If thiosemicarbazone derivative (10a) is already complexed to a metal centre, and Z is also a thiosemicarbazone complex, the product (13a) is a binuclear metal thiosemicarbazone complex.
  • the present invention provides a metal complex of formula (I) as defined above, wherein Z is a complex of a transition metal with a bis(thiosemicarbazone) or a thiosemicarbazone.
  • Z is a complex of a transition metal with a bis(thiosemicarbazone)
  • that complex may itself be a complex of formula (I).
  • Certain of such binuclear bis(thiosemicarbazone) complexes may be prepared by reaction of (at least) two equivalents of the m ⁇ r ⁇ o-keto-thiosemicarbazone (V) with a dithiosemicarbazide (U) in the presence of a salt of M according to the following scheme:
  • Q is -Ll- or -L1-R1-L3- wherein Ll, L3 and Rl are as defined above for formula (I).
  • binuclear thiosemicarbazone derivatives of formula (Ie) may be prepared by reaction of a dithiosemicarbazone and a thiosemicarbazide according to the following scheme:
  • complexes employed in the invention wherein Ll is -N(R7)- may be prepared according to the following scheme:
  • LG is a suitable leaving group such as Br or Cl.
  • R7 is H
  • the invention provides a process for producing a metal complex of the following formula (Ia):
  • M is a transition metal
  • a is a C 5-10 carbocyclic, C 5-10 heterocyclic, C 5-10 aryl or C 5-10 heteroaryl ring, which ring is unsubstituted, substituted or part of a fused bi-, tri-, tetra- or polycyclic ring system, wherein the or each further ring of said fused bi-, tri-, tetra- or polycyclic ring system is independently selected from a Cs -10 carbocyclic ring, a C 5-10 heterocyclic ring, a C 5-10 aryl ring and a C 5-10 heteroaryl ring, wherein the ring system is unsubstituted or substituted;
  • X and X' which are the same or different, are independently selected from N and P; Y and Y', which are the same or different, are independently selected from S, O,
  • each R5 is independently selected from H, C 1 -C 6 alkyl and a group comprising an electron donor group, which donor group is separated by two carbon atoms from the N or P atom to which R5 is attached;
  • Ll and Ll' which are the same or different, are each independently selected from a covalent bond and a linker group selected from -alk-, -C(O)-, -alk-C(O)-, -C(O)O-,-alk- C(O)O-, -OC(O)-, -alk-OC(O)-, -0-, -alk-O-, -N(R7)-, -alk-N(R7)-, -N(R7)C(0), -alk- N(RT)C(O)-, -C(O)NCRT), -alk-C(0)N(R7), -C(S)-, -alk-C(S)-, -S-, -alk-S-, -C(S)N(RT)-, - alk-C(S)N(R7)-, -N(R7)C(S)-, -alk-N(RT)-,
  • Rl and Rl' which are the same or different, are each independently selected from hydrogen, Z, L3-Z, L3-alk-Z, and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2 .
  • Z is a moiety selected from a biologically active molecule, a fluorophore, a cytotoxin, an amino acid, a peptide, an oligopeptide, a polypeptide, a sugar, a group containing a label, a leaving group which is replaceable by a group containing a label, and a complex of a transition metal with a bis(thiosemicarbazone) or a thiosemicarbazone;
  • R2 and R2' which are the same or different, are each independently selected from H and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, amino, C 1-10 alkylamino, di(C 1-1 o)alkylamino, C 3-20 carbocyclyl, C 3-20 heterocyclyl, C 3-20 heteroaryl, aryl, aryloxy, -alk-C 3-20 carbocyclyl, -alk-C 3-20 heterocyclyl, -alk-C 3-20 heteroaryl, and -alk-aryl, which C 1-20 alkyl, C 2-20 alkenyl and C 2-20 alkynyl are optionally interrupted by N(R7), O, S or arylene;
  • -alk- is unsubstituted or substituted C 1-20 alkylene which is optionally interrupted by N(R7), O, S or arylene; and R7 is H, C 1-6 alkyl, C 3-10 cycloalkyl or aryl; provided that Ll, Rl and R2 may form, together with the N atom to which Ll and R2 are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; and provided that Ll ', Rl' and R2' may form, together with the N atom to which Ll ' and R2' are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; which process comprises treating, in the presence of a solvent, a salt of M with either:
  • the invention further provides a process for producing a metal complex of the following formula (Ia) by transmetallation:
  • M is a transition metal
  • a is a Cs -10 carbocyclic, C 5-10 heterocyclic, C 5-1O aryl or C 5-I0 heteroaryl ring, which ring is unsubstituted, substituted or part of a fused bi-, tri-, tetra- or polycyclic ring system, wherein the or each further ring of said fused bi-, tri-, tetra- or polycyclic ring system is independently selected from a C 5-10 carbocyclic ring, a C 5-10 heterocyclic ring, a C 5-10 aryl ring and a C 5-10 heteroaryl ring, wherein the ring system is unsubstituted or substituted;
  • X and X' which are the same or different, are independently selected from N and P;
  • Y and Y' which are the same or different, are independently selected from S, O, N(R5) and P(R5), wherein each R5 is independently selected from H, C 1 -C 6 alkyl and a group comprising an electron donor group, which donor group is separated by two carbon atoms from the N or P atom to which R5 is attached;
  • Ll and Ll' which are the same or different, are each independently selected from a covalent bond and a linker group selected from -alk-, -C(O)-, -alk-C(O)-, -C(O)O-,-alk ⁇ C(O)O-, -OC(O)-, -alk-OC(O)-, -0-, -alk-O-, -N(R7)-, -alk-N(R7)-, -N(R7)C(O), -alk- N(R7)C(0)-, -C(0)N(R7), -alk-C(
  • Z is a moiety selected from a biologically active molecule, a fluorophore, a cytotoxin, an amino acid, a peptide, an oligopeptide, a polypeptide, a sugar, a group containing a label, a leaving group which is replaceable by a group containing a label, and a complex of a transition metal with a bis(tbiosemicarbazone) or a thiosemicarbazone;
  • R2 and R2' which are the same or different, are each independently selected from H and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, amino, C 1-10 alkylarnino, di(C 1-10 )alkylamino, C 3-20 carbocyclyl, C 3-20 heterocyclyl, C 3-20 heteroaryl, aryl, aryloxy, -alk-C 3-20 carbocyclyl, -alk-C 3-20 heterocyclyl, -alk-C 3-2 o heteroaryl, and -alk-aryl, which C 1-20 alkyl, C 2-20 alkenyl and C 2-20 alkynyl are optionally interrupted by N(R7), O, S or arylene;
  • -alk- is unsubstituted or substituted C 1-2O alkylene which is optionally interrupted by N(R7), O, S or arylene;
  • R7 is H, C 1-6 alkyl, C 3-10 cycloalkyl or aryl; provided that Ll, Rl and R2 may form, together with the N atom to which Ll and R2 are attached, an unsubstituted or substituted C 3 .
  • M' is either (i) a transition metal other than M or (ii) a main group metal; and a, X', X, Y', Y 5 R2, R2', Rl, Rl', Ll and Ll' are as defined above for the metal complex of formula (Ia).
  • the invention further provides a process for producing a metal complex of the following formula (Ib):
  • M is a transition metal; either (i) b is a bond and c is not a bond, or (ii) c is a bond and b is not a bond;
  • L is a ligand comprising an electron donor group
  • a is a C 5 - 10 carbocyclic, C 5-10 heterocyclic, C 5-10 aryl or C 5-10 heteroaryl ring, which ring is unsubstituted, substituted or part of a fused M-, tri-, tetra- or polycyclic ring system, wherein the or each further ring of said fused bi-, tri-, tetra- or polycyclic ring system is independently selected from a C 5-10 carbocyclic ring, a C 5-10 heterocyclic ring, a C 5-10 aryl ring and a C 5-10 heteroaryl ring, wherein the ring system is unsubstituted or substituted;
  • X and X' which are the same or different, are independently selected from N and P;
  • Y and Y' which are the same or different, are independently selected from S, O, N(R5) and P(R5), wherein each R5 is independently selected from H, C 1 -C 6 alkyl and a group comprising an electron donor group, which donor group is separated by two carbon atoms from the N or P atom to which R5 is attached;
  • Ll and Ll' which are the same or different, are each independently selected from a covalent bond and a linker group selected from -alk-, -C(O)-, -alk-C(O)-, -C(O)O-,-alk- C(O)O-, -OC(O)-, -alk-OC(O)-, -0-, -alk-O-, -N(R7)-, -alk-N(R7)-, -N(R7)C(O), -alk- N(R7)C(0)-, -C(O)N(R7), -alk-C(O)N(R7), -alk-C(O)N(R7), -C(S)-, -alk-C(S)-, -S-, -alk-S-, -C(S)N(R7)-, - alk-C(S)N(R7)-, -N(R7)C
  • Rl and Rl ' which are the same or different, are each independently selected from hydrogen, Z, L3-Z, L3-alk-Z, and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, amino, C 1-1O alkylamino, di(C 1-10 )alky
  • Z is a moiety selected from a biologically active molecule, a fluorophore, a cytotoxin, an ammo acid, a peptide, an oligopeptide, a polypeptide, a sugar, a group containing a label, a leaving group which is replaceable by a group containing a label, and a complex of a transition metal with a bis(thiosemicarbazone) or a thiosemicarbazone;
  • R2 and R2' which are the same or different, are each independently selected from H and a substituted or unsubstituted group selected from C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, amino, C 1-10 alkylamino, di(C 1-10 )alkylamino, C 3 .
  • -alk- is unsubstituted or substituted C 1-20 alkylene which is optionally interrupted by N(R7), O, S or arylene;
  • R7 is H, C 1-6 alkyl, C 3-10 cycloalkyl or aryl; provided that Ll, Rl and R2 may form, together with the N atom to which Ll and R2 are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted C 3-20 heteroaryl group; and provided that Ll ', Rl ' and R2' may form, together with the N atom to which Ll ' and R2' are attached, an unsubstituted or substituted C 3-20 heterocyclyl group or an unsubstituted or substituted Cs -20 heteroaryl group; the process comprising treating a compound of formula (Ia) as defined above, with either: (i) L; or
  • the metal complexes of formula (I) are taken up into a range of human cancerous cell lines, and exhibit cytotoxicity towards those cell lines.
  • the cell lines used were: IGROV
  • HeLa an immortal cell line derived from cervical cancer cells
  • Conditions which may be treated by the metal complexes and pharmaceutical compositions of formula (I) include conditions characterised by undesirable cellular proliferation, that is to say, conditions characterised by an unwanted or undesirable proliferation of normal or abnormal cells. Such conditions may involve neoplastic or hyperplastic growth of any type of cell.
  • conditions characterised by undesirable cellular proliferation include, but are not limited to, benign, pre-malignant, and malignant cellular proliferation, including but not limited to, neoplasms and tumours (e.g., histocytoma, glioma, astrocytoma, osteoma), hypoxic tumours, cancers (e.g., lung cancer, small cell lung cancer, gastrointestinal cancer, bowel cancer, colon cancer, breast carinoma, ovarian carcinoma, prostate cancer, testicular cancer, liver cancer, kidney cancer, bladder cancer, pancreas cancer, brain cancer, sarcoma, osteosarcoma, Kaposi's sarcoma, melanoma) and leukemias.
  • neoplasms and tumours e.g., histocytoma, glioma, astrocytoma, osteoma
  • hypoxic tumours e.g., cancers (e.g., lung cancer, small cell lung cancer, gastrointestinal cancer, bowel cancer,
  • Certain complexes of formula (I) have the potential to be hypoxic selective. Hypoxic cells have a lower than normal oxygen concentration. Typically, the partial pressure of oxygen falls topOj ⁇ 3 mmHg of the normal concentrations (20 - 80 mmHg), occurring usually as a result of insufficient blood supply to the affected tissue which in turn can lead to anaerobic respiration and the lowering of cellular pH from an accumulation of lactic acid. Since the complexes of formula (I) have been shown to be cytotoxic, the complexes of ' formula (I) that are hypoxic selective may be useful in therapy targeted specifically to hypoxic regions. Such hypoxic selective complexes of formula (I) are thus particularly suitable candidates for use in the therapy of hypoxic tumours.
  • Hypoxic selective complexes also have the potential to be used as imaging agents to visualise hypoxic tissue in a wide range of oncological, neurological and cardiological applications.
  • the complex of formula (I) as defined herein is hypoxic selective.
  • M is Cu.
  • the copper complexes of formula (I) show fast and reversible reduction couples at biologically compatible potentials, rendering them potentially useful hypoxic imaging and therapeutic agents.
  • hypoxic selectivity of such complexes may be manipulated by suitable selection of X, X', Y and Y'. By varying these atoms and groups it is possible to exert control over factors which may influence hypoxic selectivity such as pK a , reduction potential and stability of a particular redox state of the central metal atom (for instance, the stability of the Cu(I) state when the metal is copper).
  • Complexes employed in the present invention, including copper complexes have enhanced fluorescence compared with known thiosemicarbazone complexes of the same metal. The uptake of these intrinsically fluorescent species, into a range of human cancer cell lines, was observed using fluorescence imaging.
  • the zinc(II) complexes of formula (I) showed particularly strong fluorescence emission with respect to known Zn thiosemicarbazone compounds (including known Zn bis- thiosemicarbazone compounds with aliphatic backbones), and showed promising uptake into a range of cancer cells.
  • the copper(II) analogues also showed fluorescence. Indeed, it was possible for the first time to observe the uptake of a copper(II) complex into cells by fluorescence emission. It has not previously been possible to observe the uptake or cellular distribution of Cu(II) bis(thiosemicarbazone) complexes using fluorescence. Typically, thiosemicarbazone complexes of metals other than copper, such as zinc, were used to model the uptake mechanism that would be expected of the corresponding Cu complex. A disadvantage of that method, however, was that it did not indicate the distribution in cells that would be expected of corresponding Cu complexes. This was because, unlike the zinc complexes, the copper complexes are redox active (i.e.
  • the intrinsic fluorescence of the copper complexes of formula (I) gives rise to the possibility of optical imaging of hypoxia.
  • the fluorescent properties of the complexes employed in the invention can be used to track their uptake in living cells and show where the complexes are being localised. They also allow the distribution of the complexes within cells to be monitored. These properties can be extremely useful for diagnostic and other clinical purposes. For example, fluorescence can be used to check whether a particular complex is taken up into a particular diseased cell line and where in the cells the complex becomes localised. This can be useful for determining whether that complex would be suitable for imaging that cell line or for therapy of such cells.
  • the present invention provides complexes of formula (I) as defined above which are fluorescent.
  • M is typically Zn, Cu, or a further transition metal in an oxidation state that results in electronic properties that do not quench fluorescence, such as d 6 or d 10 .
  • further transition metals include Cd(II),
  • M is Zn, Cd or Cu. More typically, M is Zn.
  • the invention provides fluorescent complexes that are taken up by a human cancer cell line. In this embodiment the fluorescence of the complexes allows the distribution of the complexes within the cells to be monitered.
  • M is Zn or Cu. More typically, M is Zn.
  • Complexes employed in the invention may be radiolabeled with metastable metal radionuclides which are useful in medical imaging techniques such as PET (Positron Emission Tomography) and SPECT (Single Photon Emmission Computerised Tomography).
  • Radioisotopes suitable for SPECT include 99m Tc, 111 In, 67 Ga, 131 I and 123 I.
  • 99m Tc has found widespread use as a result of its facile separation from 99 Mo on an ion exchange column, its suitable energy of 141 KeV and its ideal half life of 6 hours, making it the most widely used imaging agent for SPECT.
  • PET is the mapping of radiopharmaceutical distribution based on detection of annihilation photons resulting from the interaction of a positron with an electron. It is useful for oncological applications and has increased sensitivity with respect to SPECT (10-100 fold). However randomness, scattering and photons emitted with insufficient energy will reduce contrast.
  • the short half lives of positron emitters mean that they must be produced close to where they are needed. They are made either by nuclear generators via parent/daughter radionuclide decay (though this is rare) or by use of a cyclotron (as for the isotopes of 11 C, 13 N, 15 0, 19 F and 64 Cu).
  • the positron, ⁇ + , emitting isotopes 89 Zr, 60 Cu, 61 Cu 5 62 Cu and 64 Cu find use in PET imaging. It is widely recognised that PET will be one of the primary tools for the diagnosis of cancer and for the monitoring of the effects of therapy. 64 Cu is of particular interest, since its half-life (12.7 h) is sufficiently long to allow for the synthesis of many radiopharmaceutical compounds. The long-lived Cu isotope is also of interest in the context of PET (positron emission tomography) imaging of the biodistribution of drugs as part of the drug screening process.
  • PET positron emission tomography
  • the complexes employed in the invention are candidates for use as imaging agents, using either radioactive imaging techniques such as PET and SPECT, or a nonradioactive optical technique, such as fluorescence.
  • the radiolabeled complexes may be suitable for both non-radioactive and radioactive imaging, which may be used in combination. Indeed, when combined with fluorescence imaging, radioactive imaging techniques such as PET and SPECT could provide an extremely powerful tool in the clinical diagnosis and treatment of disease.
  • radioactive imaging techniques such as PET and SPECT could provide an extremely powerful tool in the clinical diagnosis and treatment of disease.
  • the copper and gallium complexes employed in the invention show fluorescence, if a radioisotope of copper is used (e.g. 64 Cu) there is the possibility of simultaneous optical imaging (due to the insrinsic fluorescence of the copper complex) and PET imaging (due to the radionuclide).
  • the present invention further provides a diagnostic agent or medical imaging agent which comprises a complex of formula (I) as defined above.
  • M is Zn 5 Ga, In, Tc or Cu.
  • M may be 99m Tc, 111 Li, 67 Ga, 89 Zr 5 60 Cu, 61 Cu, 62 Cu or 64 Cu.
  • M is Zn, Ga 5 In, Zr or Cu.
  • M may be 111 In, 67 Ga, 89 Zr, 60 Cu, 61 Cu, 62 Cu or 64 Cu.
  • M is Zn or Cu.
  • M is 60 Cu, 61 Cu, 62 Cu and 64 Cu.
  • M is 64 Cu.
  • the diagnostic agent or medical imaging agent is suitable for both radioactive imaging and non-radioactive imaging, wherein the complex comprises a radionuclide.
  • the non-radioactive imaging is by fluorescence.
  • M may be Cu or any transition metal in an oxidation state that results in electronic properties that do not quench fluorescence, such as d 6 or d 10 . Examples of such further metals include Zn (II), Cd(II), Re(I) 5 Tc(I) and Ru(II).
  • M is Zn, Cd or Cu.
  • the radioactive imaging is by PET or SPECT.
  • M may be a radionuclide of copper, such as 64 Cu.
  • the complex may comprise a group Z, wherein Z is a group containing a label, wherein the label is a fluorophore.
  • M may be Zn or any other transition metal in an oxidation state that results in electronic properties that do not quench fluorescence, provided that the complex comprises a group Z 5 wherein Z is a group containing a label, the label being a radioisotope suitable for use in radioactive imaging.
  • the radioisotope is 18 F, 11 C, 14 C, 3 H, 99m Tc 5 111 In, 67 Ga, 89 Zr, 123 I or 188 Re. More typically, the label is 18 F.
  • the complexes employed in the invention are candidates for use as dual therapy and imaging agents, for example in the dual therapeutic treatment and imaging of cancer tumours and other conditions characterised by undesirable cellular proliferation.
  • the present invention further provides the use of a complex of formula (I) as defined above in the manufacture of a medicament for use as a diagnostic agent, an imaging agent and/or a therapeutic agent.
  • the medicament is for use as a combined imaging and therapeutic agent.
  • M is Cu or Zn.
  • M is typically a radionuclide of copper. More typically, M is 64 Cu.
  • M may be a stable (non-radioactive) isotope of Cu.
  • the complex may comprise a group Z 5 wherein Z is a group containing a label, the label being a fluorophore.
  • the fluorescence of the Cu complex may be further enhanced, if desired.
  • M is Zn.
  • the complex may or may not comprise a group Z wherein Z is a group containing a label, the label being a radioisotope.
  • the radioisotope is 18 F, 11 C, 14 C, 3 H, 99m Tc, 111 In, 123 I or 188 Re. Most typically the label is 18 F.
  • a complex of formula (I) in which Rl or Rl ' is either Z or a group substituted by Z might hinge on whether the complex is hypoxic selective or not.
  • the complex is not hypoxic selective then attachment of an appropriate biologically active molecule as Z will permit the complex to be used as a targeted diagnostic imaging agent (for instance, when Z is a monoclonal antibody or a peptide).
  • Biologically active molecules in this context may be those mentioned above, for instance therapeutic agents and agents which target the conjugated complex to the desired site in vivo. They include cytotoxins, monoclonal antibodies, folic acid and peptides.
  • Cu is typically the metal M in complexes employed in the invention which are hypoxic selective.
  • the complex can act as a hypoxic selective vector to deliver a range of functional molecules to the desired site in vivo, in particular to tumours, giving rise to a wide range of biomedical applications.
  • Those applications include therapy, diagnosis and medical imaging, examples of which are as follows.
  • the complex can for instance be used in the SPECT imaging of tumours (using 99m Tc as the radionuclide) or in PET imaging (using 18 F as the radionuclide ).
  • SPECT imaging of tumours using 99m Tc as the radionuclide
  • PET imaging using 18 F as the radionuclide
  • the radionuclide used in Z is a beta emitting radionuclide such as 188 Re 5 the complex can be used in targeted radiotherapy.
  • Z in formula (I) is a therapeutic agent such as a cytotoxin and M is Cu
  • the resulting cytotoxin complex can be targeted specifically to tumours.
  • Z is or comprises a reductively activated cytotoxin, and the copper complex releases the active agent in vivo once it is trapped inside the cells.
  • the complexes employed in the present invention have a wide range of potential applications. Some of these applications may be modified, enhanced or realised by attachment of the appropriate group Z to the complex.
  • the present invention provides complexes as defined above, wherein LV, -Rl' and/or -Ll and -Rl, and R2 and R2', are such that the complex has one or more terminal functional group that provides a means for simple reaction with another compound to which the skilled person wishes to attach it.
  • the present invention provides complexes which may serve as a building block for producing a diagnostic agent, which can be added to another compound as and when is convenient depending on the application.
  • terminal groups that may be suitable for such building blocks include Narylcarboxylate, - COOH, -CHO, -NH 2 , and -OH.
  • terminal groups that may be suitable for such building blocks include Narylcarboxylate, - COOH, -CHO, -NH 2 , and -OH.
  • terminal groups that may be suitable for such building blocks include Narylcarboxylate, - COOH, -CHO, -NH 2 , and -OH.
  • terminal groups that may be suitable for such building blocks include Narylcarboxylate, - COOH, -CHO, -NH 2 , and -OH.
  • Complexes employed in the present invention may be also used in a method of imaging a cell, in vitro biopsy sample or patient. Accordingly, the invention provides a method of imaging a cell or in vitro biopsy sample, which method comprises: (a) contacting the cell or in vitro biopsy sample with a complex employed in the invention as defined herein; and (b) imaging the cell or in vitro biopsy sample.
  • step (b) is imaging the cell
  • the imaging of the cell can be done using conventional techniques.
  • step (b) is imaging the in vitro biopsy sample
  • the imaging of the in vitro biopsy sample can be performed using conventional techniques.
  • the invention further provides a method of imaging a patient in need thereof, which method comprises: (a) administering to the patient a complex employed in the invention as defined herein; and (b) imaging the patient.
  • Step (b), of imaging the patient can be done using conventional techniques.
  • the imaging is fluorescence imaging.
  • the invention provides a method of imaging a cell or in vitro biopsy sample, which method comprises: (a) contacting the cell or in vitro biopsy sample with a complex employed in the invention as defined herein which complex is fluorescent; and (b) imaging the cell or in vitro biopsy sample using fluorescence imaging.
  • the invention further provides a method of imaging a patient in need thereof, which method comprises: (a) administering to the patient a complex employed in the invention as defined herein which complex is fluorescent; and (b) imaging the patient using fluorescence imaging.
  • the imaging may be PET or SPECT.
  • the invention provides a method of imaging an in vitro biopsy sample, which method comprises: (a) contacting the in vitro biopsy sample with a complex employed in the invention as defined herein, which complex comprises a radionuclide suitable for PET imaging or SPECT imaging; and (b) imaging the in vitro biopsy sample using PET imaging or SPECT imaging.
  • the invention provides a method of imaging a patient in need thereof, which method comprises: (a) adrninistering to the patient a complex employed in the invention as defined herein, which complex comprises a radionuclide suitable for PET imaging or SPECT imaging; and (b) imaging the patient using PET imaging or SPECT imaging. Radionuclides suitable for PET and SPECT imaging respectively are discussed herein.
  • the imaging is both fluorescence imaging and eiher PET or SPECT imaging.
  • the fluorescence imaging and eiher PET or SPECT imaging may be simultaneous.
  • the invention provides a method of imaging an in vitro biopsy sample, which method comprises: (a) contacting the in vitro biopsy sample with a complex employed in the invention as defined herein, which complex is fluorescent and comprises a radionuclide suitable for PET imaging or SPECT imaging; and (b) imaging the in vitro biopsy sample using fluorescence imaging and PET imaging or SPECT imaging.
  • the invention provides a method of imaging a patient in need thereof, which method comprises: (a) administering to the patient a complex employed in the invention as defined herein, which complex is fluorescent and comprises a radionuclide suitable for PET imaging or SPECT imaging; and (b) imaging the patient using fluorescence imaging and PET imaging or SPECT imaging. Radionuclides suitable for PET and SPECT imaging respectively are discussed herein.
  • Some key design features of the metal complexes for use in the present invention as optical andTET imaging probes, with increased cytotoxicity include: (a) They are more soluble in biological media than known Zn(II) analogues.
  • the higher intrinsic fluorescence, coupled with solubility and stability in biologically compatible medium should facilitate the monitoring of cell delivery and biodistribution of imaging probes in cancer cells.
  • the present invention provides a pharmaceutical composition comprising a complex of the invention as defined above and a pharmaceutically acceptable carrier or diluent.
  • a complex of the invention is formulated for use as a pharmaceutical composition also comprising a pharmaceutically acceptable carrier or diluent.
  • the compositions are typically prepared following conventional methods and are administered in a pharmaceutically suitable form.
  • the complex may be administered in any conventional form, for instance as follows:
  • compositions intended for oral use may be prepared according to any method known in the art for the manufacture of pharmaceutical compositions and such compositions may contain one or more agents selected from the group consisting of sweetening agents, flavouring agents, colouring agents and preserving agents in order to provide pharmaceutically elegant and palatable preparations. Tablets contain the complex in admixture with non-toxic pharmaceutically acceptable excipients which are suitable for the manufacture of tablets.
  • excipients may be for example, inert diluents, such as calcium carbonate, sodium carbonate, lactose, dextrose, saccharose, cellulose, corn starch, potato starch, calcium phosphate or sodium phosphate; granulating and disintegrating agents, for example, maize starch, alginic acid, alginates or sodium starch glycolate; binding agents, for example starch, gelatin or acacia; lubricating agents, for example silica, magnesium or calcium stearate, stearic acid or talc; effervescing mixtures; dyestuffs, sweeteners, wetting agents such as lecithin, polysorbates or lauryl sulphate.
  • inert diluents such as calcium carbonate, sodium carbonate, lactose, dextrose, saccharose, cellulose, corn starch, potato starch, calcium phosphate or sodium phosphate
  • granulating and disintegrating agents for example, maize
  • the tablets may be uncoated or they may be coated by known techniques to delay disintegration and adsorption in the gastrointestinal tract and thereby provide a sustained action over a longer period.
  • a time delay material such as glyceryl monostearate or glyceryl distearate may be employed.
  • Such preparations may be manufactured in a known manner, for example by means of mixing, granulating, tableting, sugar coating or film coating processes.
  • Formulations for oral use may also be presented as hard gelatin capsules wherein the complex is mixed with an inert solid diluent, for example, calcium carbonate, calcium phosphate or kaolin, or as soft gelatin capsules wherein the active ingredient is present as such, or mixed with water or an oil medium, for example, peanut oil, liquid paraffin, or olive oil.
  • Aqueous suspensions contain the complex in admixture with excipients suitable for the manufacture of aqueous suspensions.
  • excipients are suspending agents, for example, sodium carboxymethylcellulose, methylcellulose, hydroxypropylmethyl-cellulose, sodium alginate, polyvinylpyrrolidone gum tragacanth and gum acacia; dispersing or wetting agents may be naturally-occurring phosphatides, for example lecithin, or condensation products of an alkylene oxide with fatty acids, for example polyoxyethylene stearate, or condensation products of ethylene oxide with long chain aliphatic alcohols, for example heptadecaethyleneoxycetanol, or condensation products of ethylene oxide with partial esters derived from fatty acids and a hexitol such as polyoxyethylene sorbitol monooleate, or condensation products of ethylene oxide with partial esters derived from fatty acids and hexitol anhydrides for example polyoxyethylene sorbitan monooleate.
  • dispersing or wetting agents may be naturally-occurring phosphatides, for example lecithin, or condensation products of an al
  • the said aqueous suspensions may also contain one or more preservatives, for example, ethyl or n-propyl p-hydroxybenzoate, one or more colouring agents, such as sucrose or saccharin.
  • Oily suspension may be formulated by suspending the complex in a vegetable oil, for example arachis oil, olive oil, sesame oil or coconut oil, or in a mineral oil such as liquid paraffin.
  • the oily suspensions may contain a thickening agent, for example beeswax, hard paraffin or cetyl alcohol.
  • Sweetening agents, such as those set forth above, and flavouring agents may be added to provide a palatable oral preparation. These compositions may be preserved by this addition of an antioxidant such as ascorbic acid.
  • Dispersible powders and granules suitable for preparation of an aqueous suspension by the addition of water provide the active ingredient in admixture with a dispersing or wetting agent, a suspending agent and one or more preservatives.
  • a dispersing or wetting agent e.g., a suspending agent
  • Suitable dispersing or wetting agents and suspending agents are exemplified by those already mentioned above. Additional excipients, for example sweetening, flavouring and colouring agents, may also be present.
  • the pharmaceutical compositions of the invention may also be in the form of oil-in- water emulsions.
  • the oily phase may be a vegetable oil, for example olive oil or arachis oils, or a mineral oil, for example liquid paraffin or mixtures of these.
  • Suitable emulsifying agents may be naturally-occurring gums, for example gum acacia or gum tragacanth, naturally occuring phosphatides, for example soy bean lecithin, and esters or partial esters derived from fatty acids an hexitol anhydrides, for example sorbitan mono-oleate, and condensation products of the said partial esters with ethylene oxide, for example poly oxy ethylene sorbitan monooleate.
  • the emulsion may also contain sweetening and flavouring agents.
  • Syrups and elixirs may be formulated with sweetening agents, for example glycerol, sorbitol or sucrose.
  • a syrup for diabetic patients can contain as carriers only products, for example sorbitol, which do not metabolise to glucose or which only metabolise a very small amount to glucose.
  • Such formulations may also contain a demulcent, a preservative and flavouring and coloring agents.
  • sterile injectable aqueous or oleaginous suspensions This suspension may be formulated according to the known art using those suitable dispersing of wetting agents and suspending agents which have been mentioned above.
  • the sterile injectable preparation may also be a sterile injectable solution or suspension in a non-toxic parenterally-acceptable diluent or solvent, for example as a solution in 1,3-butane diol.
  • acceptable vehicles and solvents that may be employed are water, Ringer's solution and isotonic sodium chloride solution.
  • sterile, fixed oils are conventionally employed as a solvent or suspending medium.
  • any bland fixed oil may be employed including synthetic mono- or diglycerides.
  • fatty acids such as oleic acid find use in the preparation of injectables;
  • Cu(ATSM), Zn(ATSM), Zn(ATSEt) and Zn(ATSPh) are used herein.
  • Cu(ATSM) refers to a compound of the following formula (X), in which M is Cu and each R is methyl.
  • Zn(ATSM) refers to a compound of the following formula (X), in which M is Zn and each R is methyl.
  • Zn(ATSM/ A) refers to a compound of the folio whig formula (X), in which M is Zn, one R is methyl and the other R is amino.
  • Zn(ATSEt) refers to a compound of the following formula (X), in which M is Zn and each R is ethyl.
  • Zn(ATSPh) refers to a compound of the following formula (X), in which M is Zn and R is phenyl.
  • Mono(thiosemicarbazone) ligands, metal complexes of the mono(thiosemicarbazone) ligands, and Ni, Zn and Cu bis(thiosemicarbazone) complexes were synthesized and characterised as described in the following Comparative Examples 1 to 7 and Examples 8 to 16.
  • NMR spectra were run on a Varian Mercury 300 MHz spectrometer at 298K in d ⁇ -DMSO solution and referenced to residual solvent peak.
  • IR spectra were run on a Perkin Elmer 1000 FT-IR spectrometer using KBr discs.
  • UV spectra measurements were run in DMSO using a Perkin Elmer UV/Vis/NIR spectrometer Lambda 19.
  • Fluorescence spectra were measured in DMSO using a Hitachi F-4500 Fluorescence Spectrophotometer.
  • ES-MS was carried out by the Inorganic Chemistry Spectrometry Service using a MicroMass LC time of flight electrospray mass spectrometer.
  • HPLC was done on a Gilson Unipoint instrument using a reverse phase column with a CH 3 CN/H 2 O mobile phase. Elemental analyses were performed by the University of Oxford Inorganic Chemistry Laboratory analytical department.
  • X-ray crystal structural data was collected using an Enraf Nonius DIP2000 image plus plate diffractometer. Fluorescence Microscopy images were made using a Leica confocal microscope.
  • Mono(4-methyl-3-thiosemicarbazone)-acenaphthenequinone (3) was prepared as described in Comparative Example 3.
  • Mono(4-methyl-3-thiosemicarbazone)-acenaphthenequinone (0.367 g, 1.366 mmol), and zinc acetate bishydrate (0.150 g, 0.683 mmol) were then suspended in ethanol (50ml) with 10 drops of HCl (35 %) and heated under reflux for 24 hours.
  • the resulting red-orange solid was then isolated from the reaction mixture by filtration of the hot reaction mixture.
  • the solid was washed with diethyl ether (50 ml).
  • the solid (4) was then dried under vacuum.
  • Zinc bis(4-methyl-3-thiosemicarbazide) acenaphthenequinone was prepared as described in Example 12. Copper acetate bishydrate (0.105 g, 0.478 mmol) was dissolved in methanol (100 ml) to give a methanol solution of copper acetate bishydrate. To this solution was added a suspension of zinc bis(4-methyl-3-thiosemicarbazide) acenaphthenequinone (0.100 g 0.239 mmol). The resulting suspension was stirred overnight for 20 hours. A dark red solid (15) was then isolated by filtration, washed with warm methanol (20ml) and dried under vacuum. Yield (0.076 g, 0.1830 mmol, 77 %).
  • Zinc bis(4-ethyl-3-thiosemicarbazide) acenaphthenequinone (13) was prepared as described in Example 13. Copper acetate bishydrate (0.490 g, 0.224 mmol) was dissolved to give a methanol solution (100ml). To this was added a suspension of zinc bis(4-ethyl-3- thiosemicarbazide) acenaphthenequinone (13) (0.500 g 0.112 mmol). The resulting suspension was stirred overnight for 20 hours. A dark red solid (16) was then isolated by filtration, washed with warm methanol (20ml) and dried under vacuum. Yield (0.35 g. 0.798 mmol, 71%).
  • Zinc compound 12 was co-crystallised with 1,4-diaza-bicyclo [2,2,2]octane ("DABCO"). Crystals of 19 were grown from a 1 :10 solution of 12 :D ABCO in THF layered with pentane at room temperature. The molecular structure of the 1 : 1 DABCO complex 19 was determined by x-ray crystallography.
  • Zinc compound 14 was co-crystallised with DABCO. Crystals of 20 were grown from a 1 : 10 solution of 14 :D ABCO in THF layered with pentane at room temperature. The molecular structure of the 1:1 DABCO complex 20 was determined by x-ray crystallography.
  • Example 21 Spectroscopic properties of zinc(II) bis(thiosemicarbazone) compounds 12, 13 and 14, and comparison with other compounds
  • UV visible and fluorescence studies were carried out on zinc compounds 12, 13 and 14 to identify: a) whether they are intrinsic fluorescent and suitable for cell imaging; b) how they compare to other compounds, including compounds 1 to 7, acenaphthenequinone and the known compounds Zn(ATSM), Zn(ATSEt) and Zn(ATSPh); and c) how their fluorescence is altered by changing the solvent for biocompatible media, hi addition, DFT calculations were performed in order to investigate the nature of the frontier orbitals of compounds 12, 13 and 14, in order to appreciate the number and intensities of the absorption bands of those compounds.
  • Fluorescence measurements were carried out in DMSO and in a 5:95 DMSO:water solvent mix to mimic biological conditions. Fluorescence of the acenaphthenequinone starting material was observed only at a concentration of 2.0 mM in 100 % DMSO 9 with emission observed at 590 nm for excitation at 480 nm.
  • the mono substituted ligands I 5 3, 5 and 7 showed fluorescence when measured in 1.0 mM and 0.1 mM concentrations. A shift in their emission to shorter wavelengths was observed as a result of the increased conjugation, with emission at 561, 554, 546 and 562nm respectively for excitation at 480 nm.
  • This exchange with the solvent and the rearrangement of the ligand may well account for a dynamic fluorescence quenching mechanism. That mechanism may provide a rapid energy transfer route by which the excited state can relax with respect to the timescale of fluorescence. Other possible reasons for quenching might include the interactions with the solvent of intermolecular packing arrays.
  • the zinc(II) bis(thiosemicarbazone) species showed fluorescence at concentrations of
  • the bis-substituted compounds 12, 13 and 14 do not suffer from the degree of quenching observed for the mono substituted complexes 2, 4 and 6, possibly in part due to the rigid non-labile nature of the ligand set. It was possible to calculate the quantum yields for 12, 13 and 14 in DMSO and draw comparison with the corresponding bis(thiosemicarbazone) complexes which are derived from 2,3-butadione as the ligand backbone, namely Zn(ATSM), Zn(ATSEt) and Zn(ATSPh). The quantum yield (the ratio of photons emitted to photons absorbed) is calculated by the following expression:
  • Figs. Ia and Ib provide comparative fluorescence spectra.
  • Fig. Ia is a fluorescence profile comparing the fluorescence intensities of the acenaphthenequinone derived Zn complex 14 (solid line) and the corresponding butadiene-derived zinc species Zn(ATSPh) (dashed line) in DMSO at concentrations of 0.0 ImM.
  • Fig. Ib compares the fluorescence intensities of the acenaphthenequinone-derived Zn complex 12 (solid line) and the corresponding butadiene-derived zinc species Zn(ATSM) (dashed line) in DMSO at concentrations of 0.0ImM.
  • the comparative data indicates that incorporation of the naphthalene group into the backbone has led to a substantial increase in fluorescence intensity.
  • Fig. 2 compares the fluorescence intensities of 13 in (a) DMSO (solid line), and (b) 5:95 DMSO:water solvent mix (dashed line), at concentrations of 0. ImM.
  • Example 21b UV visible absorption spectra
  • UV visible measurements were carried out in DMSO and in a 5:95 DMSO:water solvent mix to mimic biological conditions. UV visible data for selected compounds is listed in Table 2 below. For all complexes the absorbance was measured at 0.0ImM concentration and ⁇ shows the strongest intensity for all complexes, with 3 to 4 times the absorbance of that observed for ⁇ 2.
  • Table 4 shows the respective relative energies for the HOMO(-l), HOMO and LUMO orbitals for each of the zinc(II) complexes, 12, 13 and 14.
  • Fig. 3 illustrates, for the case of 12, the nature of the electron density on the frontier orbitals.
  • a similar diagram for the frontier orbitals was obtained for compounds 13 and 14.
  • the shapes and energies of the frontier orbitals are similar for 12, 13 and 14.
  • the DFT calculations show similarities with results on Zn(ATSM).
  • the DFT calculated frontier orbitals show similar electron distribution with calculations done on Zn(ATSM) although here contribution from the naphthyl group is observed.
  • Fig. 4 compares the UV spectra of Zn(ATSM) (dashed line) and compound 12 (solid line).
  • the absorption bands of 12 appear at wavelengths different from those of Zn(ATSM).
  • Zn(ATSM) shows two strong absorption bands whereas compound 12 shows one strong and several weaker lower energy bands.
  • the absorption band at 435 nm for Zn(ATSM) gives rise to the most intense fluorescence.
  • the LUMO calculated does not necessarily represent the final state from which fluorescence occurs. It is therefore difficult to assign any explanation to the variation in intensity of the fluorescence from the DFT calculations.
  • the large increase in fluorescence with respect to Zn(ATSM) is likely to be due to the naphthyl group as a result of the enforced rigidity and the distribution of electron density on the backbone associated with the HOMO-LUMO absorption transition.
  • the DFT calculations are however in vacuo calculations and as such do not take into account 02950
  • Example 21 indicates that the naphthalene backbone unit leads to enhanced fluorescence of zinc bis(thiosemicarbazone) units with respect to the known aliphatic backbone compounds.
  • Example 22 In vitro fluorescence imaging study using zinc(II) bis(thiosemicarbazone) compounds 12, 13 and 14
  • Cells were cultured and fluorescence cell plates prepared according to the following methods: Cells were cultured at 37 0 C in a humidified atmosphere of 5% CO 2 in air and diluted once confluence had been reached. Cells were cultured in DMEM medium with 10% foetal calf serum (FCS) and 100U/ml penicillin. The medium contained no fluorescent indicator dyes such as phenol red and was therefore suitable for use in fluorescentstudies. Samples for fluorescence were prepared in the following way: surplus supernatant containing dead cell matter and excess protein was discarded; the live adherent cells were then washed with two 5 ml aliquots of Phosphate Buffer Saline solution to remove any remaining medium containing FCS.
  • FCS foetal calf serum
  • FCS inhibits resuspension of the cells as it contains protease inhibitors which inactivate trypsin.
  • trypsin/EDTA 500 mg/L Trypsin, 200 mg/L EDTA
  • fresh DMEM was added to the suspended cells to give a sufficient concentration of cells.
  • concentration of cells required varies between cell lines and is chosen to be optimal for achieving sufficient coverage and optimal imaging.
  • the cells were plated in a Petri dish containing a glass cover slip and left for 24 hours to adhere before fluorescence imaging measurements were made. The following data details the use of the dyes that were used in conjuction with cell uptake studied: B2007/002950
  • LysoTracker Red DND-99 is a red-fluorescent dye that stains acidic compartments in live cells such as lysosomes.
  • a lysotracker solution was made up and the cells loaded to give a final concentration of dye of 100 nM.
  • the sample was then irradiated with a 568 nm red laser and all emitted fluorescence at above 590 nm collected with images taken for 15 minutes. Fluorescence and bright field image of lysotracker and compound of interest are overlaid to see concomitant areas of uptake.
  • MitoTracker Green FM is green-fluorescent mitochondrial stain which localizes in mitochondria regardless of mitochondrial membrane potential.
  • a 1 ⁇ M solution of Mitotracker was loaded into the cells to give a final concentration of 10 nM and left for 20 minutes, bright field and fluorescent images were taken at regular intervals.
  • the Mitotracker solution available excited and emitted in a similar region to the compounds of interest. Therefore, it was not possible to observe a direct overlay comparison of Mitotracker and compound uptake in the same cell.
  • the fluorescent uptake was imaged by laser-scanning confocal microscopy (TCS NT, Leica), using the 488 nm line of an argon ion laser for excitation and the emission was long pass filtered (515 nm) and detected with a photomultiplier tube.
  • the intensity of the laser was modified to reduce the possibility of photobleaching of the cell over time and the PMT voltage adjusted to be just above the autofluorescence limit of the starting conditions, effectively recording a background image before addition of compound, whilst maximising sensitivity and ensuring the correct focal plane is in focus.
  • the compounds of interest were made up to 100 ⁇ M solutions in a 1 :99 DMSO:DMEM cell medium solvent mix. All complexes gave highly stable solutions in this solvent mix, showing no signs of precipitation over several hours.
  • a solution of complex (1 ml) was added to the cell plate containing cell medium (1 ml) to give an overall complex concentration of 50 ⁇ M with overall DMSO concentration at 0.5 %. Fluorescent images were then recorded every 30 seconds and the increase in fluorescence over time observed.
  • To interpret the intracellular distribution of the complex it was of interest to compare the fluorescence of the complexes with that of a dye with a known uptake in specific organelles of the cell. Two dyes; Lysotracker Red and Mitotracker Green were used with 12 for some very preliminary qualitative work on subcellular distribution.
  • IGROV an epithelial-like ovarian carcinoma, plated at 5,000 cells/ml, T24 - colon carcinoma, plated at 2,000 cells/ml, SW620 - bladder carcinoma, plated at 6,000 cells/ml and A431 - epidermic carcinoma, plated at 3000 cells/ml.
  • the increase in fluorescence signal for compounds 13 and 14 is shown in Fig. 10a and Fig. 10b respectively. This gives a direct indication of active uptake, which is indicative of all three species (12, 13 and 14) in this cell line.
  • the uptake of 13 in S W620 appears comparable with the IGROV study, with similar fluorescence uptake observed over the same incubation period.
  • the uptake of 14 indicates that a longer incubation is required to observe similar levels of fluorescence intensity.
  • Fluorescence uptake plots over the 60 minute Incubation are shown in Figs. 12a and 12b, for 13 and 14 respectively, revealing active cellular uptake over time. The most intense fluorescence of all the cell lines tested is observed with uptake, suggesting that the A431 cells take up more compound then the other cell lines. Both 12 and 13 show rapid uptake with intense fluorescence apparent after only 10 minutes incubation. Compound 14 shows an abnormally long delay before any fluorescence is observed but then shows an equally rapid fluorescence uptake. Without wishing to be bound by theory, this perhaps infers some form of aggregation of molecules as key to emission.
  • Figs. 14a and 14b show the increase of fluorescence with time for compounds 13 and 14 respectively.
  • Complex 13 shows comparable uptake in this cell line.
  • Complex 14 shows localised uptake and some partial nuclear uptake. As with the A431 cell line, there was negligible uptake in T24 cells for the first 20 minutes followed by a rapid increase in fluorescence intensity.
  • Cells were cultured at 37 0 C in a humidified atmosphere of 5% CO 2 in air. The cells were grown in suspension in RPMI 1640 medium (Invitrogen) with added 2mM glutamine and antibiotics (100 units/ml penicillin and lOO ⁇ g/ml streptomycin). Cells were diluted when they reached a density of about 5xlO 5 /ml.
  • Cells were seeded onto a 96 well plate at cell concentrations of approximately 2xlO 5 /ml in 200 ⁇ l of cell medium. To this 50 ⁇ l of the complex solution was added. The following methods detail how the adherant cell lines were cultured and the setup of the cytotoxicity experiment with these cell lines.
  • the adherent cells were cultured in RPMI 1640 medium as opposed to the DMEM used for fluorescence imaging as the former is the preferred medium for optimal growth.
  • RPMI 1640 medium As for the U937 cell line the adherent cells were cultured in RPMI 1640 medium as opposed to the DMEM used for fluorescence imaging as the former is the preferred medium for optimal growth.
  • the LD 50 of a compound which is the concentration of the compound that gives rise to a 50% cell death over an incubation period with respect to what is observed in medium alone.
  • the cell suspension was then made up to 1 ml with fresh medium and cell counts performed. Counts were done on both the supernatant collected and for the newly resuspended cells i.e. those still adhered after 48 hours.
  • T24 cell line A similar setup was followed for the T24 cell line. These cells were seeded at a suspended concentration of 2x10 5 cells/ml, for compound concentrations of 50, 25, 12.5 and 6.25 ⁇ M.
  • a similar setup was followed for the A431 cell line. These cells were seeded at a suspended concentration of 4x10 5 cells/ml, for compound concentrations of 100, 50, 25 and 12.5 ⁇ M.
  • the fluorescent zinc complexes 12, 13 and 14 all show a similar cytotoxic effect towards a range of human cancerous cell lines, which renders them potentially useful in the dual therapy and imaging of cancers and other proliferative diseases.
  • Example 24 Measurement of redox potentials of copper complexes 15 and 16
  • Both 15 and 16 had similar voltammagrams with essentially reversible reduction processes, corresponding to the Cu(II)/Cu(I) couple.
  • the reduction potentials, E ⁇ 2 for the two copper compounds were -0.517Vfor 15 and -0.536V for 16.
  • the corresponding reduction potential for Cu(ATSM) is -0.581V.
  • the reduction potentials of 15 and 16 are comparable to that of the hypoxic selective complex Cu(ATSM). This would suggest that complexes 15 and 16 are also likely to be hypoxic selective.
  • the experimental setup involved a tailor made EPR tube equipped with electrodes, permitting the investigation of oxidised and reduced forms in situ.
  • Solution CV-coupled EPR X- BAND spectra were recorded at room temperature, at 9.43 GHz, with a microwave power of 2 mW and a modulation amplitude of 6 G.
  • the electrochemical setup was identical to the initial CV work, with a platinum working electrode, a Ag/Ag + reference electrode and run in a DMF solution with NH 4 BF 4 support electrolyte.
  • the EPR plots in Fig. 22 show how the characteristic four-peak plot of Cu(II) equilibrates and then collapses as the potential changes from 0 V to -1.2 V and then builds back up as the potential scans back up to OV and remains constant as the potential rises to IV.
  • monoisotopic nuclei of Cu(II) 5 1 3/2.
  • Cu(I) on the other hand, there is no unpaired electron so no signal is expected.
  • Cu(II) can be reduced to Cu(I) in all cells. However, in hypoxic cells this is not reoxidised and as a result it can be trapped within the cell. In normoxic (normal level of oxygen) cells the complex is reoxidised and subsequently washed out. A crucial condition for this proposed 7 002950
  • IGROV cells were incubated with a solution of compound 15 or 16 as described in Example 22. Cell material was washed several times with non-fluorescent medium, centrifuged, separated from the liquid phase and resuspended in the electrolyte [NH 4 ][BF 4 ]. Electrochemical in-situ EPR spectra of 15 and 16 incorporated inside the tumour cells
  • HPLC showed that it is possible to make 64 Cu bis(thiosemicarbazone) acenaphthenequinones complexes cleanly by transmetallation from the corresponding zinc species.
  • concentrations Of 64 Cu which are required for detection and imaging are approximately 10 "6 M, making the detection of radiolabeled species in the presence of the non-radioactive starting material difficult. It was however possible to follow the radiolabelling by HPLC, with gamma detection, which allowed determination of the extent and efficiency of transmetallation.
  • 64 Cu was produced from cyclotron proton irradiation Of 64 Ni.
  • the 64 Cu 2+ (aq) was then purified from 64 Ni 2+ (aq) using an ion exchange column, and obtained as an aqueous 64 CuCl 2 solution in 0.1 mol dm "3 HCl.
  • 64 Cu(CH 3 CO 2 )2 was prepared and used for the radiolabelling experiments by diluting 0.2 mL 64 CuCl 2 in 0.1 mol dm "3 HCl with 0.1 mol dm '3 sodium acetate (1.8 mL, pH 5.5).
  • Radiolabelling was achieved by reacting 64 Cu(CH 3 CO 2 ) 2 (200 ⁇ L, ⁇ 10 MBq), with 100 ⁇ L of the zinc complex 13 in DMSO (1.0 mg 13 in 1 ml DMSO) and water (400 ⁇ L). The reactions were stirred at room temperature for 30 minutes, and then 25 ⁇ L of each reaction solution was removed for analysis by reverse phase radio-HPLC. A 25 min gradient elution method was employed using a water/acetonitrile mobile phase solvent system. It was possible to show, by comparison with the characterised non-radioactive equivalent (using UV detection), that 13 radiolabels cleanly. As shown in Fig.
  • the zinc(II) bis(thiosemicarbazone) acenaphthenequinone complexes in this family may be labelled cleanly with radio copper by transmetallation.
  • the copper complexes show fast and reversible reduction couples at biologically compatible potentials, which potentially renders them useful as hypoxic imaging agents and/or hypoxic therapeutic agents.
  • the copper complexes also show significant fluorescence emission when taken up in IGROV cells.
  • Example 28 Cytotoxicity studies of zinc(II) bis(thiosemicarbazone) compound 13, copper(II) bis(thiosemicarbazone) compound 16 and direct comparison with the known cytotoxic agent cis platin
  • the IGROV cell line was prepared as described in Example 23 for the other adherant cell lines, with the cells seeded at 2.5x10 5 cells/ml. A comparitive study over 48 hours was carried out. Once adherant, the IGROV cells were loaded with 100, 50, 25 and 12.5 ⁇ M concentrations of the zinc complex 13, the copper complex 16 and cis platin. Cell counts were made as described in Example 23. The data, shown in Fig. 19, suggest that the Zn complex is more cytotoxic than the analogous Cu complex. The Zn compound shows comparable cytotoxicity to cis platin.
  • the medium was then removed from the wells and the cells washed with phosphate buffered saline before more medium was added to the wells. After incubation for another 24 hours, a cell proliferation assay was performed on the plate.
  • the assay used was the CellTiter 96 aqueous one solution cell proliferation assay (Promega). This is a colorimetric method for determining the number of viable cells in a sample. After 2 hours incubation with the assay, the absorbance of each well in the plate was read automatically by a plate reader. The absorbance values for each well were then plotted against the concentration of compound in that well. This was then compared with the absorbance of a well of control cells which contained no added compound.
  • the concentration of [Zn(ATSM)] which gave an absorbance value half that of the control could then be calculated from this graph to give the LDs 0 value. All measurements were performed in triplicate for reproducibility.
  • the LD 50 for [Zn(ATSM)] in IGROV cells could not be calculated in this experiment because of the relatively low cytotoxicity of [Zn(ATSM)] in this cell line. Indeed, the absorbance of the treated wells never got below the halfway value of absorbance for the control wells, although the presence of [Zn(ATSM)] at high concentrations does cause the number of cells to diminish to approximately 87% of that of the control wells.
  • Example 30 Alternative synthesis of Zinc bis(4-allyl-3-thiosemicarbazone) acenaphthenequinone (18)
  • TFA trifluoroacetic acid
  • Crystals of 18 suitable for X-ray diffraction analysis were grown according to the following method:
  • Zinc bis(4-allyl-3-thiosemicarbazone) acenaphthenequinone (18) and 1 molar equivalent of DABCO were dissolved in the minimum of THF and mixed together in a vial. Pentane was layered on top of the resulting THF solution (THF: pentane ratio 1:2). Crystals suitable for X-ray diffraction were allowed to grow slowly over several weeks. X-ray diffraction analysis showed that a 1 : 1 ratio complex with DABCO was formed.
  • Aceanthrenequinone (0.25 g, 1.08 mMol) and Zn(OAc) 2 ⁇ H 2 O was suspended in glacial acetic acid (4.5 mL) and heated to 110 0 C.
  • 4-ethyl-3-thiosemicarbazide (1.13 g, 9.4 mMol) and a catalytic amount of TFA (0.25 mL) was added and the mixture was subsequently heated under reflux for overnight.
  • the solid was isolated by filtration whilst hot, then re-suspended in warm acetic acid (5 mL) and stirred for 15 minutes.
  • the suspension was filtered again and washed with diethyl ether (50 mL) and then dried under vacuum.
  • Compound (22) can be purified (in order to remove the mono compound 22B) by column chromatography, using a silica gel solid phase and a pentane/THF solvent mixture (e.g. 1:1 pentane:THF).
  • 9,10-phenanthrenequinone (0.25g, 1.2 mMol), 4-ethyl-3-thiosemicarbazide (0.3Ig 5 2.64 mMol) and Zn(OAc) 2 '2H 2 O (0.4g, 1.82 mMol) were added to methanol (5 mL).
  • methanol 5 mL
  • One drop of sulphuric acid was then added and the mixture was heated under reflux for 24 hours under an atmosphere of argon.
  • the reaction mixture was then filtered under gravity and washed with ethanol and diethyl ether and 23 was subsequently recrystalised from THF.
  • the desired product (23) was impurified by Zn(II) bis[mono(4-ethyl-3-thiosemicarbazide)
  • 9,10-Phenatithrenequinone (0.25 g, 1.2 mMol) and Ni(O Ac) 2 '4H 2 O (0.90 g, 3.6 mMol) were suspended in Acetic acid (5 mL) and heated to 115 0 C. To this was added 4-ethyl-3- thiosemicarbazide (1.43 g, 12.0 mMol) and the mixture was heated under reflux for 2 hours. The solid formed was isolated by filtration whilst hot and stirred in warm acetic acid for 15 minutes followed by filtration, washing with diethyl ether and drying under vacuum.
  • Example 36 Spectroscopic properties of bis(4-aIlyl-3-thiosemicarbazonato) acenaphthenequinone nickel(II), zinc(II) and copper(II) complexes (17, 18 and 21)
  • the behaviour of compound 18 was observed in HeLa cells using a Nikon TE2000-E microscope. Illumination was provided by a IOOW mercury arc lamp which was filtered for excitation at 330-380 nm and signal was collected at 523-643 nm.
  • the cells were cultured in DMEM (Dulbecco's Modified Eagle's Medium) containing phenol red indicator. In order to achieve the best possible signal to noise the cells were transferred to CPB mediumf for at least one hour prior to addition of compound 18 in order to allow any phenol red to be washed out of the cells.
  • MCF-7 breast carcinoma and IGROV, an ovarian carcinoma
  • TCS NT 5 Leica laser-scanning confocal microscopy
  • the emission was long- pass filtered (515 nm) and detected with a photomultiplier.
  • the intensity of the laser was modified to reduce the possibility of photobleaching over time and the photomultiplier (PMT) voltage adjusted to be just above the autofluorescence limit of the starting conditions, effectively recording a background image before addition of the compound, whilst maximising sensitivity and ensuring the correct focal plane was achieved.
  • PMT photomultiplier
  • Compound 18 was brought to 100 ⁇ M concentration in a 1 :99 DMSO-.DMEM solvent mix.
  • the medium contained no fluorescent indicator dyes such as phenol red.
  • Complex 18 gave stable solutions in this mixture, showing no significant precipitation over the period when the uptake was monitored (90 minutes).
  • a solution of complex 2 (1 mL) was added to the cell plate containing cell medium (1 mL) to give an overall complex concentration of 50 ⁇ M with an overall DMSO concentration of 0.5 %. Confocal fluorescence images were recorded every minute and the increase in fluorescence intensity over time was observed. The imaging showed that uptake in both MCF-7 and IGROV cells was rapid for 18 with maximum uptake being observed at 40 minutes.
  • IGROVand MCF-7 Cells culturing and fluorescence cell plates preparation
  • Cells were cultured at 37 0 C in a humidified atmosphere of 5% CO 2 in air and diluted once confluence had been reached. Cells were cultured in DMEM medium with 10% foetal calf serum (FCS) and 100 U/mL penicillin. The medium contained no fluorescent indicator dyes such as phenol red and was therefore suitable for use in confocal fluorescence imaging studies. Samples for fluorescence were prepared in the following way: surplus supernatant containing dead cell matter and excess protein was discarded; the live adherent cells were then washed with two 5 mL aliquots of phosphate buffer saline solution to remove any remaining medium containing FCS.
  • FCS foetal calf serum
  • FCS inhibits resuspension of the cells as it contains protease inhibitors which inactivate trypsin.
  • trypsin/EDTA 500 mg/L Trypsin, 200 mg/L EDTA
  • fresh DMEM was added to the suspended cells to give a sufficient concentration of cells.
  • concentration of cells required varies between cell lines and is chosen to be optimal for achieving sufficient coverage and optimal imaging.
  • the cells were plated in a Petri dish containing a glass cover slip and left for 24 hours to adhere before fluorescence imaging measurements were made.
  • HeLa Cells culturing and fluorescence cell plates preparation Cells were cultured at 37 0 C in a humidified atmosphere in air and diluted once confluence had been reached. Cells were cultured in DMEM medium with 10% foetal calf serum (FCS) and 100 U/mL penicillin. Samples for fluorescence were prepared in the following way: surplus supernatant containing dead cell matter and excess protein was discarded; the live adherent cells were then washed with two 7 mL aliquots of Phosphate Buffer Saline solution to remove any remaining medium containing FCS. FCS inhibits resuspension of the cells as it contains protease inhibitors which inactivate trypsin.
  • FCS foetal calf serum
  • the cells were incubated in 2 mL of trypsin/EDTA solution (500 mg/L Trypsin, 200 mg/L EDTA) for three minutes at 37 0 C. After trypsinising, 5 mL of DMEM was added to inactivate the trypsin and the solution was centrifuged for five minutes to remove any remaining dead cell matter. The supernatant liquid was poured off and DMEM added to the cell matter left behind to give a sufficient concentration of cells. The cells were plated in a Petri dish containing a glass cover slip and left for 24 hours to adhere. 1 hour before fluorescence imaging measurements were made, the DMEM was replaced with DMEM containing no fluorescent indicator dyes such as phenol red, therefore making it suitable for fluorescent studies.
  • trypsin/EDTA solution 500 mg/L Trypsin, 200 mg/L EDTA
  • the cytotoxicties of 18 and 21 in the cancer cell line MCF-7 were therefore evaluated.
  • Cell counts for 100, 50, 25 and 12.5 ⁇ M probe concentrations were taken over a 48 hour period. AU results are averages from four separate counts with error bars indicating the range in numbers recorded.
  • Cell counts for this cell line showed that these compounds have a strong cytotoxic effect over a broad range of concentrations; the LC 50 cytotoxic limit over 48 hours is approximately 12.5 ⁇ M.
  • the MCF-7 cells were loaded with solutions of 100, 50, 25 and 12.5 ⁇ M concentrations of the zinc complex 18, the copper complex 21 and cis-platin. Cell counts were made as described below. The data, shown in Fig. 31, suggest that the Zn complex 18 has a comparable cytotoxicity to cis-platin in this cell line, under the conditions described.
  • the cytotoxicties of 13 and 16 in the cancer cell line MCF-7 were also evaluated. Cell counts for 100, 50, 25 and 12.5 ⁇ M probe concentrations were taken over a 48 hour period. All results are averages from four separate counts with error bars indicating the range in numbers recorded. Cell counts for this cell line showed that these compounds have a strong cytotoxic effect over a broad range of concentrations.
  • the MCF-7 cells were loaded with solutions of 100, 50, 25 and 12.5 ⁇ M concentrations of the zinc complex 13, the copper complex 16 and cis-platin. Cell counts were made as described below. The data, shown in Fig. 37, suggest that the Zn complex 13 has a comparable cytotoxicity to cis-platin in this cell line, under the conditions described.
  • MCF-7 cells an adherent cell line, were cultured at 37 0 C in a humidified atmosphere of 5% CO 2 in air.
  • the cells were cultured in DMEM (Sigma) with added 10% Foetal Calf serum, 2mM glutamine and antibiotics (100 units/ml penicillin and lOO ⁇ g/ml streptomycin).
  • Cells were diluted when they reached a density of about lxlO 6 /ml.
  • Cells were seeded in 6-well plates at a suspended cell concentration of approximately 2x10 5 cells/ml in DMEM (4 mL per well). The cells were left to adhere for 6 hours.
  • the supernatant was then discarded and replaced with 4 ml fresh medium containing a solution of the compound of interest (100, 50, 25 and 12.5 ⁇ M) in DMSO to give a final overall DMSO concentration of 1%. After 48 hours, the supernatant was collected and the adhered cells washed carefully with 2xlml PBS and trypsinised with lOO ⁇ L of trypsin/EDTA solution for 5 minutes at room temperature.
  • the cell suspension was then made up to 1 ml with fresh medium and cell counts performed using a trypan blue stain and haemocytometer grid to count a sample of the cells (The trypan blue stain is taken up by dead cells but cannot permeate the cell membrane of live cells). Repeat counts of live and dead cells for each experiment were made on four separate wells. The average number of viable cells is recorded with error bars indicating the range in counts made.
  • the synthesis of the 64 Cu bis(thiosemicarbazonato) acenaphthenequinone complex by transmetallation from the zinc species 18 was investigated.
  • the concentrations of Cu required for detection and imaging are of approximately 10 "9 M, making the detection of radiolabeled species in the presence of the non-radioactive starting material difficult. It was however possible to follow the radiolabelling by HPLC, with gamma detection, which allowed determination of the extent and efficiency of the transmetallation reaction.
  • Cu was produced from cyclotron irradiation Of 64 Ni.
  • the 64 Cu 2+ (aq) was subsequently purified from 64 Ni 2+ (aq) using an ion exchange column, and obtained as an aqueous 64 CuCl 2 solution in 0.1 mol dm "3 HCl.
  • 64 Cu(OAc) 2 was prepared and used for the radiolabelling experiments by diluting 0.2 mL 64 CuCl 2 in 0.1 mol dm '3 HCl with 0.1 mol dm "3 sodium acetate (1.8 mL, pH 5.5). Radiolabelling was achieved by reacting 64 Cu(OAc) 2 (200 ⁇ L, ⁇ 10 MBq), with 100 ⁇ L of 18 in DMSO (1.0 mg 18 in 1 mL DMSO) and water (400 ⁇ L).
  • the 4 Cu-radiolabelled species may be conjugated to a biologically active molecule using standard coupling chemistry of the terminal allyl groups, which could serve to target the complex to the desired site in vivo.
  • Example 40 Fluorescence of copper complexes 15, 16 and 21
  • An advantage of the copper complexes used in the present invention is that they show fluorescence despite the presence of a d 9 paramagnetic Cu(II) centre. Coupled with the successful radiolabelling of the analogous Zn complexes to form the 64 Cu comlexes, these complexes may be suitable for both fluorescence and PET imaging.
  • Figure 35 shows the fluorescence emission spectrum of the three copper complexes 15, 16 and 21 at 100 ⁇ M in DMSO ( ⁇ ex 480nm). It is worth noting that the concentration required for these measurements (100 ⁇ M) is ten times higher than that normally used for the Zinc analogues.
  • Gallium chloride (1.864 g, 10.59 mmol) was dissolved in ethanol (50 ml). To this, a suspension of zinc bis(4-allyl-3-thiosemicarbazide) acenaphthenequinone (0.500 g 1.059 mmol) in EtOH (50 mL) was added, and the mixture was heated under reflux overnight for 20 hours. The solution was allowed to cool and the dark red solid was isolated by filtration, washed with warm ethanol (20 mL) and ether (50 mL) and dried under reduced pressure. Yield: 0.412 g, 0.805 mmol, 76 %.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Medicines Containing Antibodies Or Antigens For Use As Internal Diagnostic Agents (AREA)

Abstract

La présente invention concerne un complexe métallique représenté par la formule (I) dans laquelle M représente un métal de transition ou un métal du bloc p, et a, b, c, n, L, X, X', Y, Y', L1, L1', R1, R1', R2 et R2' sont tels que définis dans la description. Ces complexes sont utilisés en imagerie médicale et en thérapie. Cette invention concerne également des procédés de production de ces complexes.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103254266A (zh) * 2013-05-19 2013-08-21 广西师范学院 甾体锌金属配合物及其制备方法和在制备抗肿瘤药物中的应用
WO2023287857A1 (fr) * 2021-07-14 2023-01-19 Washington University Systèmes et méthodes d'imagerie spect de domaine de projection quantitative de faible quantité

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3382266A (en) * 1964-10-28 1968-05-07 Pfizer & Co C Metal chelates of substituted bis-thio-semicarbazones of cyclic 1, 2-diketones
US20030187007A1 (en) * 2001-05-30 2003-10-02 Cao Sheldon Xiaodong Inhibitors of protein kinase for the treatment of disease
WO2005084168A2 (fr) * 2003-09-08 2005-09-15 Proportional Technologies, Inc. Generateur de 62zn/62cu miniaturise permettant l'administration clinique a haute concentration d'une formulation en kit de 62cu pour preparer facilement des composes de cu-bis(thiosemicarbazone) radiomarques

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3382266A (en) * 1964-10-28 1968-05-07 Pfizer & Co C Metal chelates of substituted bis-thio-semicarbazones of cyclic 1, 2-diketones
US20030187007A1 (en) * 2001-05-30 2003-10-02 Cao Sheldon Xiaodong Inhibitors of protein kinase for the treatment of disease
US20030208067A1 (en) * 2001-05-30 2003-11-06 Cao Sheldon Xiaodong Inhibitors of protein kinase for the treatment of disease
WO2005084168A2 (fr) * 2003-09-08 2005-09-15 Proportional Technologies, Inc. Generateur de 62zn/62cu miniaturise permettant l'administration clinique a haute concentration d'une formulation en kit de 62cu pour preparer facilement des composes de cu-bis(thiosemicarbazone) radiomarques

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
DATABASE CAPLUS CHEMICAL ABSTRACTS SERVICE, COLUMBUS, OHIO, US; XP002459285 Database accession no. 1967:463894 & G. R. GUMMERUS, ET AL.: "Condensation products of some .alpha.-diketones especially 3-methyl-2-hydroxy-2-cyclopentenone with thiosemicarbazide" COMMENTALIONES PHYSICO MATHEMATICAE, vol. 32, no. 5, 1966, pages 1-43, *
G. R. GUMMERUS, ET AL.: "Über isomere Dithiosemicarbazone von Methylcyclopentenolonen" ACTA CHEMICA SCANDINAVICA, vol. 10, no. 3, 1956, pages 459-465, XP002459284 MUNKSGAARD, COPENHAGEN, DK *
J.A. MCCLEVERTY, ET AL.: "Complexes of transition metals with Schiff bases and the factors influencing their redox properties. I. Nickel and copper complexes of some diketone bis-thiosemicarbazones" JOURNAL OF THE CHEMICAL SOCIETY, SECTION A: INORGANIC, PHYSICAL, THEORETICAL, no. 17, 1970, pages 2829-2836, XP002459283 ROYAL SOCIETY OF CHEMISTRY LETCHWORTH, GB *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103254266A (zh) * 2013-05-19 2013-08-21 广西师范学院 甾体锌金属配合物及其制备方法和在制备抗肿瘤药物中的应用
CN103254266B (zh) * 2013-05-19 2016-04-13 广西师范学院 甾体锌金属配合物及其制备方法和在制备抗胃癌药物中的应用
WO2023287857A1 (fr) * 2021-07-14 2023-01-19 Washington University Systèmes et méthodes d'imagerie spect de domaine de projection quantitative de faible quantité

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