JPH09512796A - Thioether compounds for use in the preparation of bifunctional chelating agents for therapeutic radiopharmaceuticals - Google Patents

Abstract

(57) Summary: Multidentate coordination containing two or more thioether groups for complexing with ¹⁰⁵ Rh of sufficiently high specific activity for use in the preparation of therapeutic ¹⁰⁵ Rh-radiopharmaceuticals. A compound consisting essentially of children.

Description

Detailed Description of the Invention       Used in the preparation of bifunctional chelating agents for therapeutic radiopharmaceuticals                           Thioether compound   The present invention is under contract number DE-FG02-89ER60875 awarded by the Department of Energy. It was established with the support of the government. The government has certain rights in this invention.                                 Technical field   The present invention provides a chelate bond with a radioactive atom that can be used in the design of radiotherapeutic agents. Relating to compounds having biological properties. In particular, the present invention preferably provides a radioactive therapeutic agent. Is radioactive rhodium used as¹⁰⁵Related to chelating agents that can form complexes with Rh You.                               BACKGROUND OF THE INVENTION   Radiotherapeutic agents that use "non-sealed sources" by pharmaceuticals labeled with radioactive elements are: It has been used to treat cancer for decades [1,2]. Unfortunately, the FDA now accepts Only a limited number of therapeutic radiopharmaceuticals are commonly used. Tumor With a higher degree of affinity and specificity for targeting ulcers in vivo. With the advent of biomolecular carriers, the development of new drugs has become I'm interested. Monoclonal antibody (MAb), antibody fragment or single chain antibody (SCA) and And several peptides, including molecules based on peptides or avid for non-peptide receptors. Drugs are being developed and studied at a rapid pace [3-7]. These molecules are Labeling with electron-emitting radionuclides may be useful for diagnosing cancer patients in scintigraphy A drug effective for CK and PET images is manufactured [8-10].   However, the development of radiotherapeutics is much slower and problematic. Yes. For example, radionuclides that emit particles into labels of biomolecules for specific applications. It is not easy to choose [11-13]. Select the appropriate therapeutic radionuclide The choice of particle energy, half-life and pharmacokinetics, availability, ratio, Radioactivity, suitability for coupling of suitable chelating systems to radionuclides mediators, Many factors must be taken into account, including internal stability [13,14].   Many specific molecular probes have an amount of drug that can be administered (ie, typically 100 nm ol or more, often less than 20 nmol), a limited amount of binding Tumor cell populations that have a target or receptor. [15,16]. as a result, The specificity of drugs labeled with these radioactive elements should usually be high ( That is, 100 m (i / nmol)) [15, 16]. Therefore, it is the most attractive to use for these drugs. Powerful, and perhaps the only functional radionuclide, is highly specific and readily available Of. Radionuclides, which emit relatively little beta particles, are present in many patients. It can be manufactured in large quantities for treatment [11-13]. One of these radionuclides¹⁰⁵Rh [13,17 ].   ¹⁰⁵Medium-energy β particles emitted from Rh [Eβ (max) = 560 keV (7 0%) and 250 keV (30%)] are attractive for treatment but emit relatively small amounts 306 keV and 319 keV γ-rays (5% and 19%, respectively) can be cured if desired. It could be used for video as well as medical treatment.¹⁰⁵The half-life of Rh is 1.44d It will be in good agreement with the pharmacokinetics of the receptor binding agent or MAb fragment. that is,¹⁰⁵Disintegrates into Rh (half-life = 4.4 hours)¹⁰⁵Generate Ru¹⁰⁴Ru (> 99) Easy to "indirectly" with no carrier added (NCA) form due to the impact of (% concentration) Can be manufactured in large quantities. High specific activity¹⁰⁵To get Rh¹⁰⁵Separate Rh from Ru Uru [18]. If necessary, it is highly radioactive as a fission product (ie 10^Threecuri e)¹⁰⁵It is also possible to obtain Rh [17].   Therapeutic agents are primarily labeled with beta-particle emitting radionuclides. A lot of expectations Radionuclides are produced in nuclear reactors, but in some cases they are also produced in accelerators [1 1-13]. Several chelates to maintain the association of these β-emitters with drugs Structures have been used [19-23]. Many of these structures are not stable enough Most, but not all, of the appropriate means of removing radioactivity from tissues that are not of interest. Does not provide steps or proportions [23,24]. Therefore, high radiation doses are released to normal tissues. The rate of treatment is reduced. This means that the radiation dose that can be safely emitted to the target tissue. Lower. Of a new radionuclide chelate that binds radiometals to radiopharmaceuticals Development is needed. In addition, it is very stable in vivo but emits from normal tissue. Label the radioelement to produce a chelate with improved potency-eliminating properties New methods must be taken to certify technology.   Designed to minimize the in vivo release of metal radionuclides from radiopharmaceuticals Bifunctional chelating agents have been used to form stable metal complexes. For example, Diethylenetriaminepentaacetic acid (DTPA) is a fairly stable chelate with various metals. To form However, due to one of its five carbonyl groups, Coupling with clonal antibody is not acceptable for various radionuclides in vivo It showed stability [14]. A side group attached to one of the carbon atoms on the ethylene bridging group The in vitro and in vivo stability is improved by the combination with the compound. Unfortunately , The stability characteristics of this chelate and its analogues with all radioactive metals are It is not ideal and the removal of radioactivity from some non-target organs is inadequate.   Rh (III) forms various chemically inactive complexes under physiological conditions Due to the fact [25], a new formulation for the formation of new therapeutic radiopharmaceuticals¹⁰⁵Lab with Rh For preparing a bifunctional chelating agent¹⁰⁵Rh (III) is particularly attractive. Misfortune However, the formation of the desired Rh (III) chelate in aqueous media usually requires significant excess. It requires severe conditions (eg, reflux for 2 hours or more) [26-29]. Moreover, a large excess Polymerized forms of Rh are also often produced using ligands [30,31].   Complex formation of Rh with various thioether compounds has recently been reported [28-32]. middle Rh (III), which is a moderately soft acid, is usually a “soft” donor atom (eg, titanium). It will form stable complexes with ligands containing ethers [32,33]. Blake et al. , 1,5,9,13-Tetrathiacyclohexadecane (16-ane-S_Four) Is Rh (III) chloride and tra ns-Rh (III) Cl₂(1989) [32]. Low thioether compound The ability to complex Rh (III) in high yield at ligand concentration has not been studied . Unfortunately, almost all thermodynamically stable metal chelates are in vivo. Insufficient stability and low amount of ligand will not lead to high yields. Out Applicants have used ligand amounts in the nanomolar range under relatively mild conditions,¹⁰⁵Rh The possibility of forming a chelate with a tetrathio macrocycle or its analogues was investigated. . Unlike other prior art chelates, these chelants are in very small amounts. Very stable with ligands of (ie <20 nmol)¹⁰⁵High yield and ratio of Rh chelate Indicates the ability to form with radioactivity.                               SUMMARY OF THE INVENTION   According to the invention,¹⁰⁵Two or more thioether groups to form a complex with Rh Compounds consisting essentially of polydentate ligands are provided. The invention further provides:¹⁰⁵Rh and 1 6-ane-S_Four-Diol, 14-ane-NS_ThreeAnd 14-ane-N₂S₂Provides a stable complex with a ligand You.                             Brief description of the drawings   Other advantages of the invention will be found in the following detailed description when discussing with the accompanying drawings. It will be easily acknowledged to be understood by reference.   Figure 1 shows (a) as obtained from MURR in acidic solution.¹⁰⁵Rh-chloride, and And           (B) 16-ane-S_Four-Rh (III) after complex formation with diol Is a radiation chromatogram of electrophoresis of   Figure 2 shows 16-ane-S as a function of heating time at various temperatures._Four-With diol The complex formation yield is shown (10 in a 0.5 ml solution of pH 4 containing 15% ethanol). μg 16-ane-S_Four-Researched with diols),   Figure 3 shows human sera at pH 7.4, 8.5 and pH 7.4 to 7.8 for more than 4 days. In¹⁰⁵Rh-16-ane-S_Four-Shows stability of diol (sample is (a) 0.05 M sodium phosphate to pH 7.4 in 0.09% brine at room temperature (RT), (B) Using 0.1M sodium bicarbonate, 0.09% salt water at room temperature (RT). PH 8.5 and (c) pH 7.4 to 7.8 in human serum at 37 ° C. Have),   FIG.¹⁰⁵Rh-chloride, and           B.¹⁰⁵Rh-14-ane-NS_Three Is a radiation chromatogram of electrophoresis of   Figure 5 shows the used 14-ane-NS_ThreeAs a function of the amount of¹⁰⁵Rh (III) 14-ane-NS_ThreeWith The complex formation yield is shown (minimum amount of ligand = 1 μg (about 4 nmol), 20% 1 hour in a pH 4 solution containing tanol¹⁰⁵Rh-chloride and 14-ane-NS_ThreeHeat And analyzed by TLC and electrophoresis), and   FIG. 6 is a function of temperature¹⁰⁵Rh-14-ane-NS_ThreeShows the complex formation yield of (20% 55, 60, 70 or 80 ° C for 1 hour in an aqueous solution containing pH 4 containing ethanol 12 μg of 14-ane-NS at_ThreeWere cultured).                             Detailed Description of the Invention   In general, the present invention¹⁰⁵Two or more thioetes to form a complex with Rh There is provided a compound consisting essentially of a polydentate ligand containing a ruthenium group. That is, the compound is¹⁰⁵ Polydentate containing Rh core and two or more thioether (TE) groups for binding metal And a ligand. can get¹⁰⁵Rh-TE complex is highly stable in vitro and in vivo And is formed with a small amount of ligand (ie <50 nmol).   The ligand containing TE¹⁰⁵It forms a complex with Rh, and the ratio of metal to ligand is 1 :. Form a chelate that is 1. The complex formation method is a one-step, high-yield reaction (see Example In particular) currently available or industrially manufactured¹⁰⁵Using Rh-synthon,^{1 05} Rh-chelates can be formed.¹⁰⁵Rh-chelates¹⁰⁵Rh (III) -syntho Contain n and thioether ligands in very small amounts (ie less than 50 nmol) After mixing in aqueous solution, under relatively mild conditions (ie, moderate pH, 60 to It is produced in high yield (ie 85% or more) with heating at 80 ° C. for 1 hour. This This is important in solving the problems of the prior art.¹⁰⁵Rh-chelate Severe conditions (ie, reflux for more than 2 hours) and the use of large amounts of complexing ligands are required. It was important. Under these conditions¹⁰⁵Rh-chelate synthesis is usually sensitive The specificity or binding affinity of the biomolecule is destroyed and is usually too low to be used as a radiopharmaceutical. Unusable specific activity¹⁰⁵Rh-compound is produced.   Manufactured according to the present invention¹⁰⁵The Rh-chelate is soluble in aqueous solution and at 37 ° C. It was found to be stable in the serum of goats. These chelates are also wide It is stable over a wide pH range (ie pH 1-10). This high stability is due to pH Allows compound localization in different regions of the body and is stable by different routes of administration Is important in that   Especially,¹⁰⁵Polydentate containing thioether (TE) used to form a complex with Rh The ligand may be characterized by the formula:   Macrocyclic ligand containing two or more thioether groups   Essentially X is¹⁰⁵A “donor” atom that forms a complex with Rh (ie S, O or N) or includes them.   Various thioether macrocycles, including the structures above, are prepared by known methods. Uru [34,35]. R¹, R², R^Three, And R^FourAre all the same or different, and-(CH₂ )₂-,-(CH₂)_Three-, -CH₂CH (CH_Three) CH₂-,-(CH₂)_Four-, -CH₂C H (R^Five)-, -CH₂CH (R^Five) CH₂-, -CH (R^Five) CH₂CH₂-And-CH₂C H (CH₂R^Five) CH₂Selected from the group consisting of: R^FiveIs -H, or used for normal binding A side chain containing a group to be used (eg, —OH, NH₂, COOH, -NCS, activation Ester). R^FiveIs also -OCH_Three, -OC₂H_FiveAnd form a complex Not a ligand or¹⁰⁵Uses ligands chelated to Rh as target agents for biomolecular attack It consists of a group for attaching a linking group used to improve lipophilicity for binding. Can be selected from the group. R^1-4Is also another coordination atom, eg R⁶-X^Four-R⁶(In the formula R⁶Is-(CH₂)₂-,-(CH₂)_Three-, -CH₂CH (CH_Three) CH₂-,-(CH₂)_Four− , -CH₂CH (R^Five)-, -CH₂CH (R^Five) CH₂-, -CH (R^Five) CH₂CH₂-And And -CH₂CH (CH₂R^Five) CH₂− And R^FiveIs -OH, NH₂, Is COOH ). X^1-4Is¹⁰⁵An atom capable of coordinating Rh (III) or an S, O or N donor source A group containing a child, X¹, X², X^ThreeAnd X^FourIs one of X is -S- and the other is -S-, -O-, NH, NR⁷(R in the formula⁷Is H, -CH_ThreeOr improve lipophilicity or Is an uncomplexed ligand or "preformed"¹⁰⁵Rh-chelate is an organic matter Is a group bonded to the N-atom for bonding to the child attack targeting agent) They may be the same or different.   As mentioned above, the ligand may not form a complex. That is,¹⁰⁵Rh and It does not have to form a complex. Alternatively, the ligand forms a complex with rhodium It may be referred to as "preformed". Therefore, it does not form a complexOr Preformed ligands can bind to the receptor-seeking molecule.   There are several chemical methods for attaching ligands or metal chelates to biomolecules Article [36,37], a non-complexed TE ligand or¹⁰⁵Rh-TE complex One or more of these methods can be used to bind to a biomolecule attack target molecule that seeks a receptor. Will be used. These include acid anhydrides, aldehydes, arylisothiosines. Includes the use of anates, activated esters or N-hydroxysuccinimides [3 6,37].   The ligand may also be a linear ring-opened chain ligand containing one or more thioether groups. Yes. The compound is exemplified by the formula: R in the formula¹, R²And R^ThreeAre all the same or different, and-(CH₂)₂-,-(CH₂ )_Three-, -CH₂CH (CH_Three) CH₂-,-(CH₂)_Four-, -CH₂CH (R^Five)-, -C H₂CH (R^Five) CH₂-, -CH (R^Five) CH₂CH₂-And-CH₂CH (CH₂R^Five) C H₂Selected from the group consisting of: R^FourAnd R^FiveAre the same or different and H or Is an alkyl group or -OH, NH₂, A linking group containing a functional group such as COOH . -OCH_Three, -OC₂H_FiveAnd a ligand not forming a complex or (¹⁰⁵Kireh to Rh To bind the biotin-targeted agent to the biomolecule attack targeting agent. Other functional groups may be used to attach the linking group used to improve lipophilicity. X^1-4Is¹⁰⁵An atom or group capable of coordinating Rh (III). X¹, X², X^Three, And X^FourIs , X is one or more S-atoms and the other is -S-, -O-, -SH, NH and N. R⁷All selected from the group consisting of are the same or different. R⁷Is H , -CH_ThreeAnd a ligand which improves lipophilicity or does not form a complex or¹⁰⁵Rh and The ligand forming the complex is Selected from the group consisting of groups attached to the N-atom for attachment to the target child attack agent Is done.   The above equation is¹⁰⁵Identification of target tissue when forming a chelate bond with Rh Vivo binding and pharmacokinetics with respect to the location of cancer (ie, cancer cells or tumors) Modifying ligands to prepare ligands that can be molecularly engineered to optimize properties It is shown that the present invention has a characteristic that it provides a possible capability.   For example, an uncomplexed ligand or the corresponding¹⁰⁵Rh-chelates are bioactive A peptide by using a side chain that has already been used for binding to a sex molecule, and Molecules that seek other receptors, such as antibodies and antibody fragments (target molecules of attack) [36,37]. The conjugation reaction consists of benzyl isothiocyanate and bromoacetate. Such as toamide, N-hydroxysuccinimide, activated ester and aldehyde It may contain various reactive groups [15].   To make the chelate more polar or hydrophilic, add other side chains to the functional group. sell. To increase the hydrophilicity of the resulting chelate, a carboxyl or hydro A charged group such as a xyl group can be attached to the C-backbone or other site (ie, N-atom) Can be added to.   Or you get¹⁰⁵In order to increase the hydrophobicity of Rh-chelates, Non-polar groups (eg, alkyl, alkoxy, etc.) can be added to the ligand backbone. straight When one of the terminal groups of the chain ligand is a thiol group, it is neutral and lipophilic¹⁰⁵Rh-chelate Is formed. These alterations result in non-specific binding in normal radiation-sensitive tissues. And maximizes selective and maximal binding affinity to tumor cells while minimizing localization Have the following properties¹⁰⁵Rh-may be systematically transformed to provide a pharmaceutical.   All of the above modifications are applicable to the compounds prepared according to the invention and Radiopharmaceutical specificity to design in-vivo attack targets, medications and substance changes We show that these compounds can be modified to alter the binding, removal and absorption of compounds. You.   The thioether ligands used according to the invention are either commercially available or commercially available. It may be manufactured by methods similar to those outlined in Appendix [34,35]. Main chain of ligand The above functional atom (eg, N-atom) or group attached to the backbone of the ligand (eg, -OH, amine or carboxyl group) side chain attachment by standard methods Is done. For example, the commercially available 14-ane-NS shown below_ThreeMacrocyclic ligands are halogenated alkanes Reacting a kill with an N-atom on a single ring to form various thioether derivatives Be induced by.     Similarly, commercially available 16-ane-S_Four-Diol (1,5,9,13-tetrathiacyclohexane-3 , 11-diol) is as follows to attach a single side chain (R) to the ligand: Can be denatured. The R group can then be used to attach a bioactive molecule [36,37 ].   A radiopharmaceutical is a drug that binds to an attack target molecule to provide the properties of a radiotherapeutic agent. Have enough chelate¹⁰⁵Used to localize Rh to a site Means that. Therefore,¹⁰⁵Chelates containing Rh are peptides, antibodies or Other receptors directed against specific antigens or other receptors on the target cells It is bound to an attack target molecule, such as the desired molecule. Sufficient stability according to the invention The compound formed with high specific activity possessed (ie, 100 curie / nmol or more) Injected, circulates in the patient's system and joins the target tissue at the site Radiotherapy may be provided. As mentioned above, preferred compounds of the present invention are shown below. With high yield¹⁰⁵Two or more thioether groups that form a complex with high specific activity with Rh Including above. As described above, the tetrathia macrocycle which is an example of the present invention (16-ane-S_FourThe All)¹⁰⁵Allows formation of chelate with high specific activity by chelating with Rh The species are formed at low ligand concentration.   Formed as shown below¹⁰⁵Rh-16-ane-S_Four-For 4 days for diol chelate It is stable at and above physiological pH. Used in the following experimental studies This model S_FourThe ligand may be a macrocyclic compound alone or¹⁰⁵Alive any of the Rh-chelates It contains two hydroxyl groups that can be used to attach to the molecule. Therefore, S_Four New to ligands and their analogues¹⁰⁵Used to prepare therapeutic radiopharmaceuticals of Rh There is a significant possibility to do.   The advantages of the invention are numerous. The compounds prepared according to the present invention are stable and , Form a single species of clear structure.¹⁰⁵Rh (III) -16-ane-S_Four-Diol chelate Form in high yield under relatively mild conditions (ie, 60 to 90 minutes at 65 ° C). Is made. These mild conditions include amine, carboxyl, or hydroxyl. Significantly with other groups on the protein, such as¹⁰⁵Rh (II I) Since it does not form a complex,¹⁰⁵Rh (III) is already bound to the target molecule for biogenic molecule attack Is S_FourIt can chelate selectively with the moiety. can get¹⁰⁵Rh-Pharmaceutical¹⁰⁵Attack Rh It can be used to selectively localize on target cells. S_FourOther examples other than ligand system Even if the thioether group is replaced with an N-atom, the yield is high.¹⁰⁵Rh-complex is formed And   The following uses very small amounts of ligand according to the invention (less than 50 nmol, Often less than 20 nmol of thioether ligand) in high yield¹⁰⁵Rh-chelates Is an example of using three different specific thioether macrocyclic ligands.   Some chemical methods of attaching ligands or metal chelates to biomolecules are described in the literature. [36,37] is fully described and the uncomplexed TE ligand or¹⁰⁵Rh-TE complex One or more of these methods are used to bind the body to the target molecule for biomolecular attack. These include acid anhydrides, aldehydes, aryl isothiocyanates, activated esters. Includes the use of ter or N-hydroxysuccinimide [14].Example 1   ¹⁰⁵Rh-16-ane-S_Four-Formation of diol   Obtained from Missouri University Reagent Reactor (MURR)¹⁰⁵Rh-chloride test 16-ane-S from Aldrich Chemical Co. for reacting with “drugs”_Four-Diol The (1,5,9,13-tetrathiacyclohexadecane-3,11-diol) ligand was used. ¹⁰⁵Rh-chloride reagent¹⁰⁵Comprising a mixture of Rh (III) species,¹⁰⁵RhCl_Three(H₂O)_Three,¹⁰⁵RhCl_Four (H₂O)₂ ^-,¹⁰⁵RhCl_Five(H₂O)^-2as well as¹⁰⁵RhCl₆ ^-3It is estimated to include [38,40]. This trial Electrophoresis of drugs typically involves three main types of different anionic¹⁰⁵Rh-Seed Bum tetra, penta and hexachloro-¹⁰⁵A mixture of Rh (III) anions is shown. You. These samples are available in carrier-free (NCA) form only or in trace amounts.¹⁰⁵R h (III) was contained in an acidic HCl solution (~ 0.1 to 1 M HCl). 1 to 10 mCi (3 7 to 370 MBq)¹⁰⁵Including Rh¹⁰⁵The pH of the Rh-chloride reagent should be in the desired pH range of 1.5 to After adjusting to 8.5, an aliquot of 0.5 ml was added to 0.2 to 10 μg (1 to 50 nmol). 16-ane-S_Four-0.1 to 0.2 ml solution containing diol (containing some ethanol )). After heating the sample to a temperature of 55-80 ° C for 3 hours, the% label effect The rate was determined. 16-ane-S_Four-With diol¹⁰⁵The Rh-complex is cationic and has a pH of 4. 300 on paper strips saturated with 0.075M sodium phosphate buffer of 5 Single species as determined by electrophoresis run at V for 1 hour (FIG. 1). Profit Silica-TLC was also used for routine determination of the resulting complex. Silica-TLC plates should be 0. Development was performed using a 9% aqueous NaCl solution (ie N brine).¹⁰⁵Rh-16-ane-S_Four-J All R_fIs 0.05 to 0.10 but does not form a complex¹⁰⁵Rh-salt Compound reagent R_fWas 0.9 to 1.0. 10% CH_Three0.0 in CN aqueous solution Develop a C-18-reverse phase TLC plate with a solution containing 2M hexanesulfonic acid. When,¹⁰⁵Rh-chloride reagent is 50% CH_ThreeIn the CN? Even though¹⁰⁵Rh-16-ane- S_Four-The diol was shown to remain at the origin.¹⁰⁵Rh-16-ane-S_Four-R of diol_f Was 0.70.   A series of systematically independent changes in temperature, amount of ligand,% ethanol and pH. The results of the above experiment are summarized in Tables 1 to 3 and FIG. These results are 0.5 μg (2. (5 nmol) ligand and heating above 60 ° C for 1 to 1.5 hours With higher yield¹⁰⁵Rh-16-ane-S_Four-Indicates that a diol is obtained. Under these conditions The maximum yield in is a pH range of 3 to 6 that can be used for the cultivation of many bioactive molecules. Will be fulfilled in. Optimal¹⁰⁵To obtain the yield of Rh-complex, a very small amount of ethanol (ie 10%) is also required.   16-ane-S manufactured under similar conditions_Four-Non-radioactive chelate complexed with diol Based on a chromatographic comparison with¹⁰⁵Rh-16-ane-S_Four-The diol is As shown below¹⁰⁵Rh (III) (16-ane-S_Four-Diol) Cl₂]⁺Be attributed.   [¹⁰⁵Rh (III) (16-ane-S_Four-Diol) Cl₂]⁺Is a similar S_FourFor macrocycles Prepared by a method similar to that described by Blake et al. Of this chelate PF₆ ^-Crystallization of the salt by NMR, UV spectrum, elemental analysis and X-ray crystallography Well characterized. Electrophoresis and this yellow [on silica and reverse phase TLC¹⁰⁵Rh (III) (16-ane-S_Four-Diol) Cl₂]⁺Movement distance R^fIs¹⁰⁵Rh-16-ane-S_Four-Identical to the diol Because there is¹⁰⁵Rh-chelate is [¹⁰⁵Rh (III) (16-ane-S_Four-Diol) Cl₂]⁺It is The attribution will be obtained with a high degree of trust. This chelate is used in water near physiological pH. Stable in solution at room temperature and in human serum at 37 ° C for more than 4 days Shown (Figure 3).Example 2   14-ane-NS_ThreeWith¹⁰⁵Rh-complex formation ¹⁰⁵Rh 16-ane-S_Four-The method described above for complex formation with diols (see Example 1). 1-60 μg of 14-ane-NS donated by_Three(4,8,11-Tricia- 8-Aminocyclotetradecane) obtained from MURR¹⁰⁵React with Rh-chloride reagent Was.   ¹⁰⁵Rh (III) 14-ane-NS_ThreeThe results of complex formation with are summarized in Figures 4-6. these Data for 14-ane-NS_ThreeLigand is only 1 μg NS_ThreeUsing a ligand, pH 4 to 5 with a high yield of 90% or more¹⁰⁵Shows that it forms a cationic complex with Rh (Fig. 5). High yields are obtained at a culture temperature of 60 ° C.¹⁰⁵Rh-16-ane-S_Four-Diol As in the case of (Fig. 2),¹⁰⁵Rh-14-ane-NS_ThreeIn the case of (FIG. 6). The result of this ligand is that in the chelate with three thioether groups The presence of one N-atom provides a well-defined structure with similar yields as the tetrathia ligand.^{Ten Five} It is shown to form an Rh-chelate.¹⁰⁵Rh-14-ane-NS_ThreeChelate¹⁰⁵Rh-16-ane -S_Four-The two chelates have the same electrophoretic migration distance as the diol, so the two chelates are totally Therefore, it has the same charge (that is, +1).¹⁰⁵Rh-14-ane-NS_ThreeAlso It was also shown to be stable in an aqueous solution for 4 days or more.Example 3   14-ane-N₂S₂With¹⁰⁵Rh-complex formation ¹⁰⁵Rh 16-ane-S_Four-The method described above for complex formation with diols (see Example 1). 10 to 50 μg of 14-ane-N depending on₂S₂(1,4-dithia-8,11-diami Nocyclotetradecane) obtained from MURR¹⁰⁵Mixed with Rh-chloride reagent. pH4 After heating the solution of¹⁰⁵Rh-complex (¹⁰⁵Rh-16 -ane-S_Four-Having the same electrophoretic migration distance as diols) with a yield of 80% or more Was done. The results of these studies were two thioether groups and two amine functional groups. Even with a ligand having¹⁰⁵It shows that an Rh-complex is formed.   The above experimental results are¹⁰⁵Contains two or more thioether groups that form a complex with Rh, It shows that the ligand prepared according to the present invention can be prepared in high yield. Tested Specific ligands at low concentrations¹⁰⁵Forming a single species for complex formation with Rh Due to high specific activity¹⁰⁵The production of Rh-complexes is acceptable. The ligand should be at physiological pH. And is stable for more than 4 days. Two or more hydroxyl groups attached to the main chain of the ligand The known ligand is a macrocyclic compound or a rhodium chelate macrocyclic compound as known in the art. Can be readily used to attach biomolecules. Therefore, the present invention and those There is great potential in the preparation of therapeutic pharmaceuticals for analogues of.   Since the present invention has been described by way of illustration, the terminology used has been set forth in terms of limitations rather than limitations. It should be understood that this is a term for   Obviously, many modifications and variations of the present invention are possible in light of the above techniques. Therefore, the reference numbers are for convenience only and are not limiting in any way. It is understood that within the scope of the appended claims, the invention may be practiced other than as described. Should be.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification code Internal reference number FI C07C 323/11 7419-4H C07C 323/24 323/22 7419-4H 323/39 323/24 7419-4H 323 / 51 323/39 7106-4H 381/12 323/51 9283-4C C07D 285/00 381/12 9455-4C 327/00 C07D 285/00 9455-4C 331/00 327/00 9455-4C 339/00 331 / 00 9455-4C 341/00 339/00 7419-4H C09K 3/00 108B 341/00 9051-4C A61K 37/02 C09K 3/00 108 8615-4C 43/00 (72) Inventor Schlemper Elmer Columbi, Missouri, USA A South Scotts Boulevard 6301 (72) Inventor Katering Allen Earl USA Missouri 65203 Columbia Route North 12150 (72) Inventor Volkartwy Apex United States MO 65202 Columbia Garden DRIVE 2203

Claims (1)

[Claims] 1. High specific activity for use in the preparation of therapeutic radiopharmaceuticals¹⁰⁵Rh and complex To form two or more thioether groups and two or more other donor atoms ( (Comprising S, N or O). 2. A compound according to claim 1 containing 2.3 thioether groups. 3. A compound according to claim 1 which contains 3.4 thioether groups. 4.3. A group comprising a group containing three thioether groups and one nitrogen donor atom. A compound according to claim 1. 5. Macrocyclic compound in which the ligand has two or more thioether groups represented by the following formula The compound according to claim 1, which is   (R in the formula¹, R², R^Three, And R^FourAre all the same or different, and -CH₂− ,-(CH₂)₂-,-(CH₂)_Three-, -CH₂CH (CH_Three) CH₂-,-(CH₂)_Four−, -CH₂CH (R^Five)-, -CH₂CH (R^Five) CH₂-, -CH (R^Five) CH₂CH₂-And -CH₂CH (CH₂R^Five) CH₂R selected from the group consisting of^FiveIs -H or -O H, NH₂, COOH, -OCH_Three, -OC₂H_FiveNot forming groups and complexes containing A ligand or¹⁰⁵Coupling Rh chelating ligand to biomolecule attack targeting agent R is a group for attaching a linking group used to improve lipophilicity,^1-4 Is another coordination atom (R⁶-X^Four-R⁶) (R in the formula⁶Is -CH₂-,-(CH₂)₂ -,-(CH₂)_Three-, -CH₂CH (CH_Three) CH₂-, -CH₂CH (R^Five) CH₂−, − CH (R^Five) CH₂CH₂-, -CH₂CH (CH₂R^Five) CH₂− And R^FiveIs -OH, NH₂, A group containing COOH May be included, and X is¹⁰⁵Atom or S, O or N donor capable of coordinating to Rh (III) A group containing an atom, X¹, X², X^ThreeAnd X^FourIs one or more X-atoms or groups -S -And other is -S-, -O-, NH, NR⁷(R in the formula⁷Is H, -CH_ThreeOr parent Oil-improving or uncomplexed ligands or "preformed"¹⁰⁵R A group attached to the N-atom for attaching the h-chelate to the target agent for biomolecular attack Are all the same or different. ) 6. Ring-opening polydentate in which the ligand contains two or more thioether groups represented by the following formula The compound according to claim 1, which is a ligand.   (R in the formula¹, R², And R^ThreeAre all the same or different, and-(CH₂)₂−, -(CH₂)_Three-, -CH₂CH (CH_Three) CH₂-,-(CH₂)_Four-, -CH₂CH (R^Five) -, -CH₂CH (R^Five) CH₂-, -CH (R^Five) CH₂CH₂-And-CH₂CH (CH₂ R^Five) CH₂R is selected from the group consisting of^FourAnd R^FiveCan be the same or different , -H or alkyl group or -OH, NH₂, COOH, -OCH_Three, -OC₂H_Five A binding group containing a functional group such as and a non-complexed ligand or¹⁰⁵Rh Lipophilicity to attach chelating ligands to biomolecule attack targeting agents X is a functional group for attaching a linking group used for improvement, and X is¹⁰⁵Distribute Rh (III) X is a group containing an atom which can be positioned or an S, O or N donor atom, and X¹, X², X^Threeas well as X^FourAre all the same or different, two or more are -S-, and the other are -S-. -, -O-, NH, NR⁷(Where R⁷Is H, -CH_ThreeAnd improve lipophilicity or The ligand not forming the complex or the¹⁰⁵The ligand that forms a complex with Rh A group consisting of a group bonded to an N-atom for bonding to a biomolecule attack targeting agent? Selected from R^FourAnd R^FiveIs¹⁰⁵O, S or N donor which forms a complex with Rh Selected from groups containing ). 7. The R^FiveIs benzyl isothiocyanate, bromoacetamide, activated ester Ter, N-hydroxysuccinimide, degradable ester and aldehyde group 8. A compound according to claim 6 or 7 selected from 8. The R^1-7One or all of the carboxy groups to make the ligand more or less polar. Claimed to be hydroxylated, hydroxylated, alkylated or alkoxylated. A compound according to item 6 or 7. 9. The compound of claim 1 wherein the metal to ligand ratio is 1: 1. Ten. In order to selectively target preselected cells in vivo, the ligand can be used as an attack target. The compound according to any one of claims 1 to 9, which is bound to an attack target molecule. Compound. 11. The target molecule is a molecule that seeks peptide and non-peptide receptors, 11. A chain antibody, an antibody and an antibody fragment selected from the group consisting of 10. The compound according to the item. 12. The attack target molecule has high affinity and specificity for cancer cells. A compound according to claim 11. 13. High specific activity in a small amount of ligand or ligand complex¹⁰⁵Forms a complex with Rh Use of the compound according to claim 1 as a therapeutic radiopharmaceutical.