Metal complexes derivatized with folate for use in diagnostic and therapeutic applications

1. A composition for use in radiotherapy of a patient in need thereof comprising:

a) a folate-receptor binding ligand comprising one or more folate-receptor binding moieties, at least one of which is conjugated through its alpha carboxylate via an optional linking group to one or more macrocyclic or non-macrocyclic metal-chelating ligand radicals at least one of which is chelated to a radioactive-metal capable of providing a radiotherapeutic effect; and

b) a pharmaceutically acceptable carrier.

2. The radiotherapeutic composition of claim 1 wherein said folate receptor binding ligand has the structure of formula II:

wherein R 0 is a folate-receptor binding moiety of formula:

each X is independently —O—, —S—, —NH—, or —NR 1 —;

n1 is 0 or 1;

b1 is 1 to 3;

m1 is 1 to 81;

each K 1 is independently

a) a macrocyclic or non-macrocyclic metal-chelating ligand radical that is optionally chelated to a radioactive metal M 1 ,

or

b) a chemotherapeutic drug;

—K 2 is —H, -alkyl, -alkenyl, -alkynyl, -alkoxy, -aryl, -alkyl, —CON(R 2 ) 2 , -glutamate, -polyglutamate, or —K 3 ,

—K 3 is

wherein

—K 5 is either

a) a macrocyclic or non-macrocyclic metal-chelating ligand that is optionally chelated to a radioactive metal M 5 , or

b) a chemotherapeutic drug

n5 is 0 or 1;

b5 is 1 to 3;

m5 is 1 to 81;

-(A)p- and -(A)p*- are each independently optional linkers comprising a straight or branched chain wherein the moieties “A” are the same or different and selected from the group consisting of: —CH 2 —, —CHR 3 —, —CR 4 R 5 —, —CH═CH—, —CH═CR 6 —, —C═C—, —CR 9 ═CR 10 —, —C═C—, -cycloalkylidene-, -cycloalkenyl-, -arylidene-, -heterocyclo-, carbonyl (—CO—), —O—, —S—, —NH—, —HC═N—, —CR 11 ═N—, —NR 12 —, —CS—,

 and

p and p* are independently 0 to 24,

or —X-[(A)]p- and —X-[(A)p]*- may each independently be the group -Q-

wherein -Q- is —[C(R′)(R″)] s1 —[C(t)(R 21 )] s2 —[C(R 22 )(R 23 )] s3 —X3-Y—X4-;

wherein

each s1, s2, s3, and 84 is independently 0 to 2;

each X3, X4, X5, and X6 is independently a single bond, —O—, —S—, or —N(R 24 )—;

Y is a single bond, —C(R 25 )(R 26 )—, or Y1 wherein,

Y1 is —C(═X5)-X6-W—, wherein

W is a single bond, -alkylidene-, -cycloalkylidene-, -arylidene-, -alkenylidene-, or -alkynylidene-, whose carbon atoms may or may not be substituted;

t is H, R 27 , —C(O)OR 28 , —P(O)(OR 29 ))OH, —P(O)(OR 30 ))OR 31 , —P(O)(OR 32 )R 33 , —P(O)(OH)R 34 —C(O)N(R 35 )(R 36 ), or C(O)NH(R 37 );

each R′ and R″ is independently a single bond, H, alkyl, alkoxy, cycloalkyl, hydroxyalkyl, aryl, or heterocyclo, each of which is optionally substituted,

each R 3 through R 5 , R 7 , R 8 , R 21 through R 23 , and R 25 through R 27 is independently H, alkyl, alkoxy, halogen, hydroxy, cycloalkyl, hydroxyalkyl, aryl, or heterocyclo, each of which is optionally substituted;

each R 1 , R 2 , R 6 , R 9 through R 12 , R 24 , and R 28 through R 37 is independently H, alkyl, alkenyl, cycloalkyl, aryl, a 5- or 6-membered nitrogen or oxygen containing heterocycle;

or a pharmaceutically acceptable salt thereof.

3. The radiotherapeutic composition of claim 2 wherein K 1 of the compounds of formula II is a macrocyclic or non-macrocyclic metal-chelating ligand that is optionally chelated to a radioactive metal M 1 , and K 2 is other than K 3 .

4. The radiotherapeutic composition of claim 2 wherein said folate-receptor binding ligand has the structure:

5. The radiotherapeutic composition of claim 2 wherein said folate-receptor binding ligand, 12-N-(N-Pteroyl-(α)-L-glutamyl)-3,3,9,9-tetramethyl-5-oxa-4,8-diaza-2,10-dodecanedione dioxime has the structure:

6. The radiotherapeutic composition of claim 2 wherein said folate-receptor binding ligand, Technetium oxo-12-N—(N-Pteroyl-(α)-L-glutamyl)-3,3,9,9-tetramethyl-5-oxa-4,8-diaza-2,10-dodecanedione dioxime has the structure:

7. The radiotherapeutic composition of claim 2

wherein

b1=1 to 3;

m1=1;

K 2 is other than K 3 ; and

K 1 is a metal chelating ligand radical of formula IIIa-IIIc:

wherein

Q is the group —(C(RR)) m1 —Y 1 (C(RR)) m2 —(Y 2 —(C(RR)) m3 ) n —,

wherein

Y 1 and Y 2 are independently —CH 2 —, —NR—, —O—, —S—, —SO—, —SO 2 — or —Se—;

n is 0 or 1; and m1, m2 and m3 are integers independently selected from 0 to 4, provided that the sum of m1 and m2 is greater than zero;

all R and R* groups are independently —R 2 , —Cl, —F, —Br, —OR 2 , —COOR 2 , —CON(R 2 ) 2 , —N(R 2 ) 2 ; -alkyl-COOR 2 , -alkyl-C(O)—N(R 2 ) 2 ; -alkyl-N(R 2 ) 2 ; —C(O)—OR 2 ; —C(O)—N(R 2 ) 2 ; -aryl-N(R 2 ) 2 ; acyl; acyloxy; heterocyclo; hydroxyalkyl; —SO 2 —R 2 ; -alkyl-SO 2 —R 2 ; or —R 3 , wherein —R 3 is a folate-receptor binding residue of formula IV; or

two R groups, or an R group and an R* group, taken together with the one or more atoms to which they are bonded, form a saturated or unsaturated, spiro or fused, carbocyclic or heterocyclic ring which may be unsubstituted or substituted by one or more groups R or R* groups above,

with the proviso that a carbon atom bearing an R group is not directly bonded to more than one heteroatom; and that one to three of R or R* is, or contains a folate-receptor binding radical —R 3 of formula IV:

wherein R 0 is a folate-receptor binding residue of formula:

each X is independently —O—, —S—, —NH— or —N(R 2 )—;

K 2 is —H, -alkyl, -alkenyl, -alkynyl, -alkoxy, -aryl, -alkyl, —CON(R 2 ) 2 , -glutamate, or -polyglutamate;

-(A)p- is an optional linker comprising a straight or branched chain wherein the moieties “A” are the same or different and selected from the group consisting of: —CH 2 —, —CHR 3 —, —CR 4 R 5 —, —CH═CH—, —CH═CR 6 —, —CR 9 ═CR 10 —, —C≡C—, -cycloalkylidene-, -cycloalkenyl-, -arylidene-, -heterocyclo-, carbonyl (—CO—), —O—, —S—, —NH—, —HC═N—, —CR 11 ═N—, —NR 12 —, —CS—,

 and

p and p* are independently 0 to 24,

R 1 is hydrogen, a thiol protecting group, or the group —R 3 defined above;

R 2 is independently hydrogen, alkyl, cycloalkyl, hydroxyalkyl, aryl, or arylalkyl;

R 3 through R 8 are independently hydrogen, alkyl, alkoxy, hydroxy, or aryl;

R 2 and R 9 through R 12 are independently hydrogen, alkyl, or aryl;

or a pharmaceutically acceptable salt thereof.

8. The radiotherapeutic composition of claim 2

wherein

b1=1 to 3;

m1=1;

K 2 is other than K 3 ; and

K 1 is a metal chelating ligand radical of formula V:

wherein

Q is the group —(C(RR)) m1 —(Y 1 ) n —(C(RR)) m2 —(Y 2 —(C(RR)) m3 ) n1 ;

Y 1 and Y 2 are each independently —CH 2 —, —NR—, —O—, —S—, —SO—, —SO 2 — or —Se—;

n and n1 are each independently 0 or 1; and m1, m2 and m3 are independently 0 or an integer from 1 to 4; provided that m1 and m2 are not both 0, that m1+m2+n+n1 is less than 6 and that a carbon atom bearing an R group is not directly bonded to more than one heteroatom;

each R and R* group is independently: R 1 , -alkoxy, -hydroxy, -halogen, -haloalkyl, —OR 1 , —C(O)—R 1 —C(O)—N(R 1 ) 2 , —N(R 1 ) 2 , —N(R 1 )—COR 1 , -alkyl-C(O)—OR 1 , -alkyl-C(O)—N(R 1 ) 2 , -alkyl-N(R 1 ) 2 —, -alkyl-N(R 1 )—COR 1 , -aryl-C(O)—OR 1 , -aryl-C(O)—N(R 1 ) 2 , aryl-N(R 1 ) 2 —, -aryl-N(R 1 )—COR 1 , -nitrile, -acyl, -acyloxy, -heterocyclo, -hydroxyalkyl, alkoxyalkyl, hydroxyaryl, arylalkyl, —SO 2 —R 1 , -alkyl-SO 2 —R 1 , or —R 3 , wherein —R 3 is a folate-receptor binding residue of formula IV; or

two R groups, or an R group and an R* group, taken together with the one or more atoms to which they are bonded, form a saturated or unsaturated, spiro or fused, carbocyclic or heterocyclic ring which may be unsubstituted or substituted by one or more groups R or R* groups above;

each R 1 is independently hydrogen, alkyl, alkenyl, alkynyl or aryl; and

each G 1 and G 2 is each independently —OH or —(NR 2 ) 2 ;

with the proviso that at least one of G 1 or G 2 is —(NR 2 ) 2 , where each R 2 is independently hydrogen, alkyl, aryl, acyl or —R 3 ;

and one to three of R, R*, or R 2 is, or contains a folate-receptor binding radical —R 3 of formula IV:

wherein R o is a folate-receptor binding residue of formula:

each X is independently —O—, —S—, —NH— or —N(R 2 )—;

K 2 is —H, -alkyl, -alkenyl, -alkynyl, -alkoxy, -aryl, -alkyl, —CON(R 2 ) 2 , -glutamate, or -polyglutamate; wherein R 2 is independently hydrogen, alkyl, or aryl;

A is a linking group as defined in claim 1 ; and p is 0 to 24;

or a salt thereof.

9. The radiotherapeutic composition of claim 2

wherein

b 1 is 1;

m1=1;

—K 2 is other than —K 3 ;

—X-[(A)p]- is, in its entirety, the group -Q- as defined below;

—K 1 is a macrocyclic ligand radical of formula VI:

wherein

n is 0 or 1;

each m, o, and p is independently 1 or 2;

-Q- is —[C(R′)(R″)] s1 —[C(t)(R 21 )] s2 —[C(R 22 )(R 23 )] s3 —X3-Y—X4-; wherein

s1, s2, s3, and s4 are independently 0 to 2;

X3, X4, X5, and X6 are independently a single bond, —O—, —S—, or —N(R 24 )—;

Y is a single bond, —C(R 25 )(R 26 )—, or Y1,

wherein

Y1 is —C(═X5)-X6-W—, wherein

W is a single bond, -alkylidene-, -cycloalkylidene-, -arylidene-, -alkenylidene-, or -alkynylidene-, whose carbon atoms may or may not be substituted;

t is H, R 27 , —C(O)OR 28 , —P(O)(OR 29 ))OH, —P(O)(OR 30 ))OR 31 , —P(O)(OR 32 )R 33 , —P(O)(OH)R 34 , —C(O)N(R 35 )(R 36 ), or C(O)NH(R 37 );

each G is independently —C(O)OR′″, —P(O)(OR′″)OH, —P(O)(OR′″) 2 , —P(O)(OR′″)R, —P(O)(OH)R″, C(O)N(R′″) 2 , or C(O)NH(R′″);

each R′ and R″ is independently a single bond, H, alkyl, alkoxy, cycloalkyl, hydroxyalkyl, aryl, or heterocyclo, each of which is optionally substituted,

each R″ is independently a H, alkyl, cycloalkyl, hydroxyalkyl, aryl, or heterocyclo, each of which is optionally substituted,

each R 13 through R 23 , and R 25 through R 27 is independently H, alkyl, alkoxy, halogen, hydroxy, cycloalkyl, hydroxyalkyl, aryl, or heterocyclo, each of which is optionally substituted;

each R 24 , and R 28 through R 37 is independently H, alkyl, alkenyl, cycloalkyl, aryl, a 5- or 6-membered nitrogen or oxygen containing heterocycle, each of which is optionally substituted;

or R 13 together with R 15 , and R 17 together with R 18 , independently form, together with the carbon atoms in the polyazamacrocycle to which they are attached, a fused fully or partially saturated non-aromatic cyclohexyl ring which may be unsubstituted or substituted by one or more halogen, alkyl, ether, hydroxy, or hydroxyalkyl groups, and which may be further fused to a carbocyclic ring, or R 13 and R 15 are each hydrogen and R 17 , together with R 18 , forms a fused fully or partially saturated non-aromatic cyclohexyl ring as defined above, or R 13 , together with R 15 , forms a fused fully or partially saturated non-aromatic cyclohexyl ring as defined above, and R 17 and R 18 are hydrogen;

or a pharmaceutically acceptable salt thereof.

10. The radiotherapeutic composition of claim 2

wherein

—K 2 is

and both —K 1 and —K 5 are macrocyclic or non-macrocyclic metal chelates that are each optionally chelated to radioactive metals M 1 or M 5 .

11. The radiotherapeutic composition of claim 10 comprising a folate-receptor binding ligand of formula IIa:

wherein

b1 and b5=1;

m1 and m5=1;

M 1 and M 5 are radioactive metals;

n1 and n2 are independently=0 or 1;

X is —O—, —S—, or —NR 2 —;

—R 2 is -hydrogen, -alkyl, -cycloalkyl, -hydroxyalkyl, aryl, or -arylalkyl;

-[(A)p]- and -[(A)p*]- are optional linking groups;

R o is a folate-receptor binding residue of formula:

and K 1 and K 5 are metal chelating ligand radicals.

12. The radiotherapeutic composition of claim 10 wherein said folate receptor binding ligand has the structure:

13. The radiotherapeutic composition of claim 10 wherein both —X-[(A)p]-K 1 and —X-[(A)p*]-K 5 are each in their entirety, macrocyclic ligand radicals of formula VI:

wherein

n is 0 or 1;

each m, o, and p is independently 1 or 2;

Q is —[C(R′)(R″)] s1 —[C(t)(R 21 )] s2 —[C(R 22 )(R 23 )] s3 —X3-Y-X4-;

wherein

s1, s2, s3, and s4 are independently 0 to 2;

X3, X4, X5, and X6 are independently a single bond, —O, —S—, or —N(R 24 )—;

Y is a single bond, —C(R 25 )(R 26 )—, or Y1;

wherein

Y1 is —C(═X5)-X6-W—, wherein

W is a single bond, -alkylidene-, -cycloalkylidene-, -arylidene-, -alkenylidene-, or -alkynylidene-, whose carbon atoms may or may not be substituted;

t is —H, —R 27 , —C(O)OR 28 , —P(O)(OR 29 ))OH, —P(O)(OR 30 )OR 31 , —P(O)(OR 32 )R 33 , —P(O)(OH)R 34 , —C(O)N(R 35 )(R 36 ), or C(O)NH(R 37 );

each G is independently —C(O)OR′″, —P(O)(OR′″)OH, —P(O)(OR′″) 2 , —P(O)(OR′″)R″, —P(O)(OH)R″C(O)N(R′″) 2 , or C(O)NH(R′″);

each R′ and R″ is independently a single bond, H, alkyl, alkoxy, cycloalkyl, hydroxyalkyl, aryl, or heterocyclo, each of which is optionally substituted,

each R′″ is independently a H, alkyl, cycloalkyl, hydroxyalkyl, aryl, or heterocyclo, each of which is optionally substituted,

each R 13 through R 23 , and R 25 through R 27 is independently H, alkyl, alkoxy, halogen, hydroxy, cycloalkyl, hydroxyalkyl, aryl, or heterocyclo, each of which is optionally substituted;

each R 24 , and R 28 through R 37 is independently H, alkyl, alkenyl, cycloalkyl, aryl, a 5- or 6-membered nitrogen or oxygen containing heterocycle, each of which is optionally substituted;

or R 13 together with R 15 , and R 17 together with R 18 , independently form, together with the carbon atoms in the poly-aza macrocycle to which they are attached, a fused fully or partially saturated non-aromatic cyclohexyl ring which may be unsubstituted or substituted by one or more halogen, alkyl, ether, hydroxy, or hydroxyalkyl groups, and which may be further fused to a carbocyclic ring, or R 13 and R 15 are each hydrogen and R 17 , together with R 18 , forms a fused fully or partially saturated non-aromatic cyclohexyl ring as defined above, or R 13 , together with R 15 , forms a fused fully or partially saturated non-aromatic cyclohexyl ring as defined above, and R 17 and R 18 are hydrogen;

or a pharmaceutically acceptable salt thereof.

14. A composition for use in radiotherapy of a patient in need thereof comprising:

a. a folate-receptor binding ligand and

b. a pharmaceutically acceptable carrier

wherein said folate-receptor binding ligand has the structure of formula IIb:

wherein

—K 1 is —H, -alkyl, -alkenyl, -alkynyl, -alkoxy, -aryl, -alkyl, —CON(R 2 ) 2 , -glutamate, or -polyglutamate;

—K 5 is a polydentate metal chelating ligand;

M 5 is a radioactive metal;

each —X— is independently —O—, —S—, —NH—, or —NR 1 —;

b5=1 to 3, m5=1; n5 is 0 or 1;

—R o is a folate-receptor binding moiety of formula:

each -[(A)p*]- is an optional linker independently comprising a straight or branched chain made up of “p*” individual (A) moieties that are the same or different and are selected from the group consisting of: —CH 2 —, —CHR 3 —, —CR 4 R 5 —, —CH═CH—, —CH═CR 6 —, —CR 9 ═CR 10 —, —C≡C—, -cycloalkylidene-, -cycloalkenyl-, -arylidene-, -heterocyclo-, carbonyl (—CO—), —O—, —S—, —NH—, —HC═N—, —CR 11 ═N—, —NR 12 —, —CS—, and

and p* is 0 to 24;

or —X-[(A)]p*- is, in its entirety, the group -Q-

wherein

-Q- is —[C(R′)(R″)] s1 —[C(t)(R 21 )] s2 —[C(R 22 )(R 23 )] s3 —X3-Y—X4-;

wherein

s1, s2, s3, and s4 are independently 0 to 2;

X3, X4, X5, and X6 are independently a single bond, —O—, —S—, or —N(R 24 )—;

Y is a single bond, —C(R 25 )(R 26 )—, or —Y1-

wherein,

Y1 is —C(═X5)-X6-W—, wherein

W is a single bond, -alkylidene-, -cycloalkylidene-, -arylidene-, -alkenylidene-, or -alkynylidene-, whose carbon atoms may or may not be substituted;

t is H, R 27 , —C(O)OR 28 , —P(O)(OR 29 ))OH, —P(O)(OR 30 ))OR 31 , —P(O)(OR 32 )R 33 , —P(O)(OH)R 34 —C(O)N(R 35 )(R 36 ), or C(O)NH(R 37 );

each —R′ and —R″ is independently a single bond, —H, -alkyl, -alkoxy, -cycloalkyl, -hydroxyalkyl, -aryl, or -heterocyclo, each of which is optionally substituted,

each —R 3 through —R 5 , —R 7 , —R 8 , —R 21 through —R 23 , and —R 25 through —R 27 is independently —H, -alkyl, -alkoxy, -halogen, -hydroxy, -cycloalkyl, -hydroxyalkyl, -aryl, or -heterocyclo, each of which is optionally substituted;

each —R 1 , —R 2 , —R 6 , —R 9 through —R 12 , —R 24 , and —R 28 through —R 37 is independently —H, -alkyl, -alkenyl, -cycloalkyl, -aryl, or a 5- or 6-membered nitrogen or oxygen containing heterocycle;

or a pharmaceutically acceptable salt thereof.

15. The radiotherapeutic composition of claim 14

wherein —K 5 is a metal chelating polydentate ligand radical of formula IIIa-IIIc:

wherein

Q is the group —(C(RR)) m1 —Y 1 (C(RR)) m2 —(Y 2 —(C(RR)) m3 ) n —,

wherein

Y 1 and Y 2 are independently —CH 2 —, —NR—, —O—, —S—, —SO—, —SO 2 — or —Se—;

n is 0 or 1; and m1, m2 and m3 are integers independently selected from 0 to 4, provided that the sum of m1 and m2 is greater than zero;

all R and R* groups are independently —R 4 , —Cl, —F, —Br, —OR 5 , —COOR 5 , —CON(R 5 ) 2 , —N(R 5 ) 2 , -alkyl-COOR 5 , -alkyl-C(O)—N(R 5 ) 2 , -alkyl-N(R 5 ) 2 , —C(O)OR 5 , —C(O)N(R 5 ) 2 , -aryl-N(R 5 ) 2 , acyl, acyloxy, heterocyclo, hydroxyalkyl, —SO 2 —R 5 , -alkyl-SO 2 —R 5 , or —[R 3 ]—;

wherein each —[R 3 ]— is, in its entirety, the linking group -[(A)p*]- that serves to couple the metal chelating ligand radical -M 5 to —X—;

each —R 4 is independently —H, -alkyl, -alkoxy, -hydroxy, cycloalkyl, -hydroxyalkyl, -aryl, or -heterocyclo, each of which is optionally substituted;

each —R 5 is independently —H, -alkyl, -aryl, -cycloalkyl or -hydroxyalkyl, each of which is independently substituted;

with the provisos that a carbon atom bearing an —R group is not directly bonded to more than one heteroatom; and that one to three R or R* groups on —K 5 is —[R 3 ]—;

or a pharmaceutically acceptable salt thereof.

16. The radiotherapeutic composition of claim 14 wherein said folate-receptor binding ligand, N-Pteroyl-γ-glutamyl-APADO3A, has the structure:

17. The radiotherapeutic composition of claim 14 containing the folate-receptor binding ligand 12-N-(N-Pteroyl-γ-L-glutamyl)-3,3,9,9-tetramethyl-5-oxa-4,8-diaza-2,10-dodecanedione dioxime, having the structure:

18. The radiotherapeutic composition of claim 14 containing the folate-receptor binding ligand Technetium oxo 12-N-(N-Pteroyl-γ-L-glutamyl)-3,3,9,9-tetramethyl-5-oxa-4,8-diaza-2,10-dodecanedione dioxime, having the structure:

19. The radiotherapeutic composition of claim 2 wherein both K 1 and K 5 of formula II are metal chelating ligand radicals that are chelated to a radioactive metal.

20. The radiotherapeutic composition of claim 2 , for radiotherapy of tissues that overexpress folate binding protein, wherein either K 1 , or both K 1 and K 5 is chelated to a radioisotope selected from the group consisting of 153 Samarium, 156 Holmium, 165 Dysprosium, 203 Lead, 186 Rhenium, 188 Rhenium, 88 Yttrium, 90 Yttrium, 211 Bismuth 212 Bismuth, 211 Bismuth, and 214 Bismuth.

21. The radiotherapeutic composition of claim 2 wherein either K 1 , or both K 1 , and K 5 is a metal-chelating ligand radical of formula IIIa, IIIb, IIIc, that can chelate to a radioactive isotope

wherein

Q is the group —(C(RR))m1-Y 1 (C(RR))m2-(Y 2 —(C(RR))m3)n-,

wherein

Y 1 and Y 2 are independently —CH 2 —, —NR—, —O—, —S—, —SO—, SO 2 — or —Se—;

n is 0 or 1; and m1, m2 and m3 are integers independently selected from 0 to 4, provided that the sum of m1 and m2 is greater than zero;

all R and R* groups are independently —R 4 , —Cl, —F, —Br, —OR 5 , —COOR 5 , —CON(R 5 ) 2 , —N(R 5 ) 2 , -alkyl-COOR 5 , -alkyl-C(O)—N(R 5 ) 2 , -alkyl-N(R 5 ) 2 , —C(O)OR 5 , —C(O)—N(R 5 ) 2 , -aryl-N(R 5 ) 2 , acyl, acyloxy, heterocyclo, hydroxyalkyl, —SO 2 —R 5 , -alkyl-SO 2 —R 5 , or —[R 3 ]—;

wherein —[R 3 ]— is a linking group -[(A)p]- that couples the metal chelating radical of formula IIIa, IIIb, or IIIc to the remainder of the molecule;

-[(A)p]- comprises a straight or branched chain of individual moieties that are the same or different and selected from the group consisting of: —CH 2 —, —CHR 3 —, —CR 4 R 5 —, —CH═CH—, —CH═CR6-, —C═C—, —CR 9 ═CR 10 —, —C≡C -cycloalkylidene-, -cycloalkenyl-, -arylidene-, -heterocyclo-, carbonyl —(CO)—, —O—, —S—, —NH—, —HC═N—, —CR 11 ═N—, —NR 12 —, —CS—,

p is an integer from 0 to 24;

each —R 4 and —R 3 through —R 5 is independently —H, -alkyl, -alkoxy, -hydroxy, -cycloalkyl, -hydroxyalkyl, -aryl, or -heterocyclo, each of which is optionally substituted;

each —R 5 and —R 6 through —R 12 , is independently —H, -alkyl, -aryl, -cycloalkyl or -hydroxyalkyl, each of which is independently substituted;

with the provisos that a carbon atom bearing an —R group is not directly bonded to more than one heteroatom; and that at least one —R or —R* group on the metal chelating radical —K 1 of formulae IIIa, IIIb, or IIIc is —[R 3 ]—;

or a pharmaceutically acceptable salt thereof.

22. A radiotherapeutic composition of claim 2 wherein K 1 , or both K 1 and K 5 are metal chelating ligand radical of formula V that are chelated to radioactive metals

wherein

-Q- is the group —(C(RR))m1-(Y 1 )n-(C(RR))m2-(Y 2 —(C(RR))m3)n1

Y 1 and Y 2 are each independently —CH 2 —, —NR—, —O—, —S—, SO—, —SO 2 — or —Se—;

n and n1 are each independently 0 or 1; and m1, m2 and m3 are independently 0 or an integer from 1 to 4; provided that m1 and m2 are not both 0, that m1+m2+n+n1 is less than 6 and that a carbon atom bearing an R group is not directly bonded to more than one heteroatom;

each —R and —R* group is independently: —R 4 ; -alkoxy; -hydroxy; -halogen, -haloalkyl, —OR 5 , —C(O)—R 5 , —C(O)—N(R 5 ) 2 , —N(R 5 ) 2 , —N(R 5 )—COR 5 , -alkyl-C(O)—OR 5 , -alkyl-C(O)—N(R 5 ) 2 , -alkyl-N(R 5 ) 2 —, -alkyl-N(R 5 )—COR 5 , -aryl-C(O)—OR 5 , -aryl-C(O)—N(R 5 ) 2 , aryl-N(R 5 ) 2 —, -aryl-N(R 5 )—COR 5 , -nitrile, -acyl , -acyloxy, heterocyclo, -hydroxyalkyl, -alkoxyalkyl, hydroxyaryl, arylalkyl, —SO 2 —R 5 , -alkyl-SO 2 —R 5 , or —[R3]-;

wherein

—[R3]- is a linking group -[(A)p]- that links the metal chelating ligand radical of formula V to the remainder of the molecule of formulae VIIa through VIId;

wherein -[(A)p]- comprises a straight or branched chain of individual moieties that are the same or different and selected from the group consisting of: —CH 2 —, —CHR 3 —, —CH═CH—, —CH═CR 6 —, —C═C—, —CR 9 ═CR 10 —, —C≡C—, -cycloalkylidene-, -cycloalkenyl-, -arylidene-, -heterocyclo-, carbonyl (—CO—), —O—, —S—, —NH—, —HC═N—, —CR 11 ═N—, —NR 12 —, (—CS—),

p is an integer from 0 to 24;

each —R 4 and —R 3 through —R 5 is independently —H, -alkyl, -alkoxy, -hydroxy, -cycloalkyl, -hydroxyalkyl, -aryl, or -heterocyclo, each of which is optionally substituted;

each —R 5 and —R 6 through —R 12 is independently —H, -alkyl, -aryl, -cycloalkyl or -hydroxyalkyl, each of which is independently substituted; or

two R groups, or an R group and an R* group, taken together with the one or more atoms to which they are bonded, form a saturated or unsaturated, spiro or fused, carbocyclic or heterocyclic ring which may be unsubstituted or substituted by one or more groups R or R* groups above;

each -G 1 and -G 2 is independently —OH or —(NR 6 ) 2 ; with the proviso that at least one of -G 1 or -G 2 is —(NR 6 ) 2 , and each —R 6 is independently -hydrogen, -alkyl, -aryl, -acyl or —[R 3 ]—;

with the proviso that at least one —R, —R*, or —R 6 group is —[R 3 ]—;

or a pharmaceutically acceptable salt thereof.

23. A composition for radiotherapy in a kit form comprising

a) a ligand of formula II in claim 2 ;

b) a pharmaceutically acceptable reducing agent; and

c) an optional buffering agent;

in a lyophilized form.

24. A method for radiotherapy of a patient in need thereof comprising the steps of: administering the composition of claim 2 wherein K 1 or both K 1 and K 5 are chelated to an alpha or beta emitting radioisotope.

25. A method for radiotherapy of a patient in need thereof comprising the steps of: administering the composition of claim 2 wherein K 1 is chelated to an alpha- or beta-emitting radioisotope and K 2 is other than —K 3 .

26. The radiotherapeutic composition of claim 1 wherein the folate receptor binding moiety is conjugated to the remainder of the molecule through the alpha carboxylate of its glutamate residue.

27. A composition for radiotherapy in a kit form comprising

a) a folate receptor binding ligand of formula II in claim 2 ;

b) a pharmaceutically acceptable reducing agent; and

c) an optional buffering agent;

in a lyophilized form.

28. A method for radiotherapy of a patient in need thereof comprising coinjection of:

a) a folate-receptor binding ligand comprised of one or more folate-receptor binding residues conjugated to one or more macrocyclic or non-macrocyclic metal-chelating ligands at least one of which is chelated to a radioactive metal that provides a therapeutic or radiotherapeutic effect; and

b) an unmetallated derivative of said folate-receptor binding ligand, administered at a dose level sufficient to affect the resulting biodistribution of the composition.

29. A composition of claim 1 comprising:

a) a metal chelating ligand;

b) a radioactive metal chelated by said ligand;

c) a chemotherapy drug coupled to said ligand said complex coupled to

d) a folic receptor binding analog through its alpha carboxylate or through both the alpha and gamma carboxylate of folic acid, in

e) a pharmaceutically acceptable carrier.

30. A composition of claim 1 for radiotherapy in a kit form comprising

a) a folate receptor-binding analog of folate coupled through either the alpha carboxylate of folic acid or through both the alpha and gamma carboxylates of folic acid to;

b) a metal chelating ligand for complexation with a radioisotope;

c) a pharmaceutically acceptable reducing agent; and

d) a buffering agent;

in a lyophilized form.