JP2641304B2 - Intermediates for the production of bifunctional chelating ligands and their preparation - Google Patents

Description

The present invention relates to an intermediate for producing a bifunctional chelating ligand and a method for producing them. More specifically, medical diagnostics,
A production intermediate for efficiently providing a so-called bifunctional chelating ligand having a binding group with a biologically relevant substance such as a protein or a saccharide such as an antibody while strongly chelating a metal used in the therapeutic field; and It relates to the production method thereof.

<Problems to be Solved by Conventional Techniques and Inventions> In recent years, with the development of cell fusion methods, specific antibodies to various biologically relevant substances have been relatively easily obtained. Therefore, such specific antibodies include γ such as ¹¹¹ In and ^99m Tc.
Γ by binding and administering a radioactive radioactive metal
-Attempts have been made to use a camera to diagnose cancer and other diseases, and to use it as a contrast agent for diagnostic imaging using nuclear magnetic resonance by combining and administering Gd. [For example, The Journal of
Nuclear Medicine, 26 , 48
8 (1985)), International Journal of Cancer, (Int. J. Cancer, 2 , 126 (1988)).

Also, ⁹⁰ Y, ⁶⁷ Cu, ¹⁸⁶ Re, ¹⁸⁸ Re, ²¹¹ At,
^The binding of α-ray or β-ray emitting nuclides such as ²¹² Bi can provide an effective means for treating various diseases, particularly cancer. [For example, Cancer Res., 4
8 , 3270 (1988)), The Journal of Nuclear Medicine, J. Nuclear Medicine, 26 , 503 (198
5))).

Conventionally, as a method of binding such an antibody to a metal, a method in which ethylenediaminetetraacetic acid (EDTA) or diethylenetriaminepentaacetic acid (DTPA) is bound to the antibody to chelate the metal, or a method in which an EDTA or DTPA has an isothiocyano group or the like. A method using a so-called bifunctional chelating ligand in which a bonding group to a substance is introduced is known [Inorganic Chemistry, 25 , 2
772 (1986)). However, these ligands do not yet have a sufficient coordination force with the metal, and after administration, the metal is released or exchanged with the metal present in the blood, and the metal is sufficiently deposited at the target site. Cannot be integrated. Also, ED
When TA and DTPA are used, the carboxylic acid moiety, which is a ligand for the metal, is partially used for binding to the antibody. Not only does the coordination force decrease, but also the binding between the antibody and the chelating ligand is unstable.

Accordingly, bifunctional chelating ligands having stronger metal-capturing ability have been researched and developed. Among them, macrocyclic polyamine derivatives are described by Donald et al. [Journal of American Chemical Society (J. Am. Chem. Soc., 1988, 110 ,
6266), U.S. Pat. No. 4,678,667] and Parker et al. [J.Chem.Soc.Chem.Commun., 749,797 (1).
989)), EP 0238196] reports its excellent metal chelating ability.

Incidentally, methods for synthesizing the above-mentioned macrocyclic polyamine derivatives have been reported by Donald and Parker et al. However, all of these methods have drawbacks such as a long number of steps, a complicated process and a poor total yield.

Therefore, it is desired to provide a method for efficiently synthesizing a macrocyclic polyamine derivative as a bifunctional chelating ligand.

<Means for Solving the Problems> The present inventors have conducted intensive studies on an efficient method for synthesizing a macrocyclic polyamine derivative, and as a result, synthesized an iminodiacetic acid derivative and reacted the polyamine to react with the bifunctional chelate. The present inventors have found a route for efficiently synthesizing synthetic intermediates of various macrocyclic polyamine derivatives useful as ligands, and have reached the present invention.

Accordingly, an object of the present invention is to provide an intermediate for producing a bifunctional chelating ligand having excellent metal chelating ability and a method for producing them.

That is, the present invention relates to the following formula [II] And a salt thereof, and the following formula [I] And an iminodiacetic acid derivative represented by the following formula [V] H ₂ N—R ¹ —Y—R ¹ —NH ₂ ... [V] wherein R ¹ and Y have the same definition as in the above formula [II]. And a process for producing a macrocyclic polyamine dioxo derivative represented by the above formula [II] and a salt thereof.

The iminodiacetic acid derivative represented by the above formula [I] is represented by the following formula [III] [Wherein, Z, A, and R are the same as those in the above formula [I]. And a salt thereof with the following formula [I
V] XCH ₂ CO ₂ R… [IV] By reacting with an acetic acid derivative represented by the formula in the presence of a base.

In the above formulas [I], [II] and [III], Z represents a nitro group or a cyano group. After these functional groups are converted into macrocyclic polyamine dioxo derivatives according to the method of the present invention, they may be appropriately converted to functional groups capable of binding to biological substances. For example, a nitro group can bind to a biological substance by leading to an amino group, an isothiocyano group or a haloacetamide group.

In the above formulas [I], [II] and [III], A represents a divalent hydrocarbon group having 1 to 10 carbon atoms, such as methylene, ethylene, propylene, butylene, pentylene, hexylene. Linear or branched divalent hydrocarbon groups such as a group, a heptylene group, an octylene group, a nonylene group, and a decylene group; (Where k represents 0 to 3), and a divalent aromatic hydrocarbon group represented by the formula:

In the above formulas [I], [III] and [IV], R represents a hydrocarbon group having 1 to 8 carbon atoms. For example, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, isopropyl group,
Examples thereof include a sec-butyl group, a tert-butyl group, an isobutyl group, an isopentyl group, a benzyl group, and a phenethyl group. Among them, a methyl group and an ethyl group are preferable.

In the above formulas [II] and [V], R ¹ has 2 to 9 carbon atoms.
Represents one linear or branched divalent hydrocarbon group. For example, CH _{2 2} , CH _{2 3} , And CH _{2 2} , CH _{2 3} is preferred.

In the above formulas [II] and [V], Y is Wherein R ² represents a linear or branched divalent hydrocarbon group having 2 to 9 carbon atoms, n or 0 or 1 or 2. For example, as Y Etc., but especially Is preferred.

In the formulas [II] and [V], -R ¹ -Y-
It is preferable in manufacturing that the partial structure of R ¹ -be a symmetrical structure with respect to the center of Y.

The salts of the above formulas [I], [II] and [III] include, for example, hydrofluoric acid, hydrochloride, hydrobromide, hydroiodide, acetate, trifluoroacetate and boron Hydrofluoric acid, fumarate, sulfate and the like,
It is not limited to this.

X in the above formula [IV] is a halogen atom, and among them, a chlorine atom, a bromine atom and an iodine atom are preferable.

The iminodiacetic acid derivative represented by the above formula [I] is obtained by converting the amino acid derivative represented by the above formula [III] or a salt thereof into an acetic acid derivative 1 represented by the above formula [IV] in the presence of 0.5 to 5 moles of a base. It is produced by reacting with ５5 times mol. Examples of the base to be used include amino bases such as triethylamine, diazabicycloundecene, pyridine, pyrrolidine, piperidine, and morpholine, and inorganic bases such as potassium carbonate and sodium carbonate. Particularly, triethylamine and potassium carbonate are preferable. The reaction temperature is -40 ° C to 100 ° C, particularly preferably 0 to 50 ° C.
A temperature range of about ° C is employed. The reaction time varies depending on the reaction temperature, but is about 20 minutes to 10 hours. The reaction is performed in the presence of an organic medium, and the medium used is an organic medium that does not react with the reaction reagent. Examples of such a medium include N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, ethyl acetate, tetrahydrofuran, methanol, ethanol, dimethoxyethane, dioxane, chloroform, methylene chloride and the like. Particularly, N, N-dimethylformamide, tetrahydrofuran and methanol are preferred.

The iminodiacetic acid derivative obtained after such operation is appropriately selected from ordinary operations such as extraction, silica gel column chromatography, ion exchange chromatography, high performance liquid chromatography, centrifugal liquid distribution chromatography, recrystallization, and distillation. It can be isolated by applying and applying in combination.

The obtained iminodiacetic acid derivative can be converted into a salt as described above by a known method, if desired.

The macrocyclic polyamine dioxo derivative represented by the above formula [II] is obtained by adding 0.5 to 3 equivalents, more preferably 0.8 to 1.5 equivalents of the above formula [V] to the iminodiacetic acid derivative represented by the above formula [I]. Produced by reacting polyamines. The reaction temperature is in the range of −40 to 150 ° C., particularly preferably about 40 to 100 ° C. The reaction time varies depending on the reaction temperature, but is about 3 to 20 days. The reaction is performed in the presence of an organic medium, and the medium used is an organic medium that does not react with the reaction reagent. Examples of such a medium include N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, ethyl acetate, tetrahydrofuran, methanol, ethanol, dimethoxyethane, dioxane, chloroform, methylene chloride and the like. Particularly, methanol and ethanol are preferable. The concentration of each reaction reagent is 0.5M
It is preferably set to the following, and more preferably about 0.05M.

The macrocyclic polyamine dioxo derivative obtained after such an operation is subjected to ordinary operations such as extraction, silica gel column chromatography, ion exchange chromatography, high performance liquid chromatography, centrifugal liquid distribution chromatography, recrystallization, and distillation. It can be isolated by appropriately selecting and applying and applying in combination.

The obtained macrocyclic polyamine dioxo derivative can be converted into a salt as described above by a known method, if desired.

The iminodiacetic acid derivative and its salt and the macrocyclic polyamine dioxo derivative and its salt of the present invention are novel compounds not described in the literature, and are useful as intermediates for producing bifunctional chelating ligands. Also, these production methods are simple methods with fewer steps than known methods.

Hereinafter, the present invention will be described in more detail with reference to examples, and application examples of the present invention will be described. However, the present invention is not limited to these examples.

Reference Example Synthesis of N- [α- (p-nitrobenzyl) -methoxycarbonylmethyl] -N-methoxycarbonylmethylamine p-Nitrophenylalanine methyl ester hydrochloride (30.0 g, 0.115 mol) was added to N, N-dimethylformamide 250
and triethylamine (11.6g, 0.115mo
l)) was added and the mixture was stirred at room temperature for 30 minutes. After the reaction mixture was filtered to remove precipitates, the solution was concentrated under reduced pressure. The residue was dissolved in 250 ml of N, N-dimethylformamide, and methyl bromoacetate (35.2 g, 0.23 mol) was added thereto under a nitrogen atmosphere.
Then, triethylamine (23.2 g, 0.23 mol) was added, and the mixture was stirred at room temperature for 1 hour. After the reaction mixture was filtered to remove precipitates, the solution was concentrated under reduced pressure. The residue was dissolved in ethyl acetate, and this was washed with a saturated aqueous solution of sodium bicarbonate and then with a saturated saline solution.
Dry over anhydrous sodium sulfate. After that, the mixture was concentrated to obtain N- [α- (p-nitrobenzyl) -methoxycarbonylmethyl] -N-methoxycarbonylmethylamine (34.0 g, 0.115 mol, 100%). This can be used for the next reaction as it is, but it can also be purified by silica gel column chromatography (CH ₂ Cl ₂ : MeOH = 100: 1). The yield when purified is 92%
Met.

The physical properties of this compound are as follows. _{^{1 H-NMR (CDCl 3,}} δppm); 2.06 (s, 1H), 3.03-3.17 (m, 2H), 3.40 (s, 2H), 3.48 (t, 1H, J = 7Hz), 3.70 (s, 6H ), 7.40 (d, 2H, J = 9 Hz), 8.15 (d, 2H, J = 9 Hz). IR (neat, cm ^-1 ); 3350, 2970, 1755, 1730, 1610, 1520, 1435, 1350, 1110, 1015 FD-MS; m / e 296 (M) ⁺ , 297 (M + H) ⁺ detection When methanol was used as the solvent for the above, the yield was 72%.

Example 1 Synthesis of 3- (p-nitrobenzyl) -1,4,7,10-tetraazacyclododecane-2,6-dione N- [α- (p-nitrobenzyl) methoxycarbonylmethyl] -N-methoxycarbonylmethylamine (3
4.0 g, 0.115 mol) and diethylene triamine (11.9 g, 0.115 mol)
mol) in dry methanol 2 and 1
Refluxed for 0 days. The reaction solution was concentrated to about 300 ml, and allowed to stand at room temperature for 24 hours.
(Nitrobenzyl) -1,4,7,10-tetraazacyclododecane-2,6-dione (9.24 g, 27.6 mmol, 24%) was obtained.

The physical properties of this compound are as follows. ¹ H-NMR (D ₂ O / DCl, δ ppm); 3.14-3.50 (m, 8H), 3.77 (s, 2H), 4.11 (d, 2H, J = 8.5 Hz), 4.30-4.52 (m, 1H) , 7.52 (d, 2H, J = 9 Hz), 8.15 (d, 2H, J = 9 Hz). IR (KBr disc, cm ^-1 ); 3270, 3080, 2950, 1660, 1640, 1600, 1510, 1340, 1140, 1110, 1045. FD-MS; m / e 335 (M) ⁺ , 336 (M + H) ⁺ Detection mp; 230 ° C. (decomposition) <Example 2> Synthesis of 3- (p-nitrobenzyl) -1,4,7,10,13-pentaazacyclopentadecane-2,6-dione N- [α- (p-nitrobenzyl) methoxycarbonylmethyl] -N-methoxycarbonylmethylamine (2
4.3 g, 82 mmol) and triethylenetetramine (12.0 g, 82 mmo)
l) in dry methanol 1.7 and 7
Refluxed for days. The solvent was distilled off under reduced pressure, and the residue was subjected to silica gel column chromatography (CHCl ₃ : MeOH: 28% NH ₃ water = 10
0: 7: 1 to 100: 12: 2). The obtained crystals were suspended in ethyl acetate, heated and stirred, and the crystals were collected.
(P-nitrobenzyl) -1,4,7,10,13-pentaazacyclopentadecane-2,6-dione (7.10 g, 18.8 mmol, 23
%).

The physical properties of this compound are as follows. ¹ H-NMR (CDCl ₃ , δ ppm); 1.50 (br, s, 3H), 2.52-2.86 (m, 8H), 2.96-3.66 (m, 9H), 7.40 (d, 2H, J = 9 Hz), 7.42 (Br.s, 2H), 8.70 (d, 2H, J = 9 Hz), IR (KBr disc, cm ^-1 ); 3300, 2815, 1660, 1640, 1600, 1510, 1350, 1130, 1105. FD-MS m / e 379 (M + H) ⁺ detection mp; 166-167 ° C. <Application Examples of the Present Invention> The macrocyclic polyamine dioxo derivatives obtained by the method of the present invention are useful for various useful bifunctional macrocyclic chelate coordinations. Can lead to child. For example, Donald et al. Synthesized the intermediate A shown below and led to B by a method different from the present inventors. [Journal of American Chemical Society (J. Am. Chem. Soc., 1988, 110 , 6266)] According to the method of the present inventors, compound A can be easily synthesized. Further, the nitro group of the compound B can be easily led to a functional group capable of binding to a biological substance. Hereinafter, as a reference example, a method of leading the macrocyclic polyamine dioxo derivative obtained in Example 2 to B via the compound A will be described, but this does not limit the present invention.

Reference Example 1 Synthesis of 2- (p-nitrobenzyl) -1,4,7,10-tetraazacyclododecane (Compound A ) 3- (p-nitrobenzyl) -1,4,7,10- Tetraazacyclododecane-2,6-dione (6.70 g, 20 mmol) was suspended in 200 ml of dry tetrahydrofuran under a nitrogen atmosphere.
After cooling with ice, a tetrahydrofuran solution of a borane-tetrahydrofuran complex (1 M, 300 ml, 300 mmol) was added dropwise. After refluxing for 12 hours, the reaction mixture was cooled with ice, and 50 ml of water was added thereto.
50 ml of hydrochloric acid were slowly added. After distilling off the solvent tetrahydrofuran under normal pressure, the reaction mixture was concentrated while azeotroping with methanol under reduced pressure. 100 ml of water was added to the residue, washed with ether and concentrated. The residue was subjected to ion exchange chromatography (Dowex1-X8) to collect the H ₂ O eluted portion, and the solvent was distilled off. After the residue was purified by centrifugal liquid separation chromatography, the obtained crystals were separated from acetonitrile by 2%.
Recrystallized twice to give 2- (p-nitrobenzyl) -1,4,7,10-
Tetraazacyclododecane (4.47 g, 14.6 mmol, 73%) was obtained.

The physical properties of this compound are as follows. _{^{1 H-NMR (CDCl 3,}} δppm); 2.20 (br.s, 4H), 2.35-3.06 (m, 17H), 7.35 (d, 2H, J = 9Hz), 8.14 (d, 2H, J = 9Hz) _{^{, 13 C-NMR (CDCl 3}} , δppm); 39.985,44.604,46.266,46.372,46.571, 46.677,50.214,50.641,50.541,123.496, 129.838,146.486,147.431 FD-MS;. m / e 308 (M + H) + Detection JR (KBr disc, cm ^-1 ); 3330, 2850, 1595, 1515, 1460, 1440, 1340, 1110, 1065. mp; 110-111 ° C Reference Example 2 2- (p-nitrobenzyl) -1 Synthesis of 4,4,7,10-Tetraazacyclododecane-N, N ', N "N-tetraacetic acid (Compound B ) Bromoacetic acid (1.39 g, 10 mmol) was dissolved in 15 ml of water and cooled with ice.
7M KOH (2.86ml, 20mmol) was added. 2-
A solution of (p-nitrobenzyl) -1,4,7,10-tetraazacyclododecane (0.62 g, 2 mmol) in 20 ml of ethanol was added, and the mixture was stirred at 70 ° C. for 4.5 hours. The reaction mixture was adjusted to pH = 3.4 with 47% hydrobromic acid, and the deposited precipitate was collected.
(P-nitrobenzyl) -1,4,7,10-tetraazacyclododecane-N, N ', N ", N-tetraacetic acid (0.57 g, 1.05 mmol
1,52%).

The physical properties of this compound are as follows. ¹ H-NMR (D ₂ O / NaOD, δ ppm); 2.20-4.10 (m, 25H), 7.46 (d, 2H, J = 9 Hz), 8.16 (d, 2H, J = 9 Hz). IR (KBr disc, cm ^-1 ); 3430, 3110, 1680, 1515, 1455, 1345, 1250, 1080. SIMS; m / e 540 (M + H) ⁺ detection mp; 215 ° C (decomposition)

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoshinori Kato 4-3-2 Asahigaoka, Hino-shi, Tokyo Teijin Limited Tokyo Research Center (72) Inventor Eiichi Kimura 4-Misugaoka Higashi, Saeki-ku, Hiroshima-shi, Hiroshima- 9-3

Claims (9)

(57) [Claims] [1] The following formula [II] And a salt thereof. 2. In the formula [II], A is a methylene group, an ethylene group, a propylene group or (Wherein k represents an integer of 0 to 3). The macrocyclic polyamine dioxo derivative and a salt thereof according to claim 1, wherein k is an integer of 0 to 3. 3. In the above formula [II], R ¹ is CH _{2 2} or C ₂
H _{2 3} or The macrocyclic polyamine dioxo derivative according to claim 1 or 2, and a salt thereof. 4. In the formula [II], Y is Or The macrocyclic polyamine dioxo derivative according to any one of claims 1 to 3, and a salt thereof. 5. The following formula [I] And a formula [V] H ₂ N—R ¹ —Y—R ¹ —NH ₂ ... [V] A method for producing a macrocyclic polyamine dioxo derivative represented by the above formula [II] and a salt thereof, characterized by reacting with a polyamine represented by the following formula: 6. In the formulas [I] and [II], A represents a methylene group, an ethylene group, a propylene group or The method for producing a macrocyclic polyamine dioxo derivative and a salt thereof according to claim 5, wherein k represents 0 to 3. 7. The method for producing a macrocyclic polyamine dioxo derivative and a salt thereof according to claim 5, wherein R in the formula [I] is a methyl group or an ethyl group. 8. In the formula [II] and the formula [V], R ¹ is
CH _{2 2} or CH _{2 3} or The method for producing a macrocyclic polyamine dioxo derivative and a salt thereof according to any one of claims 5 to 7, wherein 9. In the formula [II] and the formula [V], Y is The method for producing a macrocyclic polyamine dioxo derivative and a salt thereof according to any one of claims 5 to 8, wherein