Crystallization method and application of fluorescent-magnetic resonance bimodal contrast agent intermediate

Abstract

The invention relates to the field of medical diagnosis imaging, in particular to a crystallization method and application of a fluorescent-magnetic resonance bimodal contrast agent intermediate. The structural formula of the fluorescent-magnetic resonance bimodal contrast agent intermediate is as shown in formula I. The crystallization method of the intermediate comprises the following steps: adding an alcohol solvent and water into a fluorescent-magnetic resonance bimodal contrast agent intermediate crude product, heating, stirring and dissolving, then adding a nitrile solvent, cooling to room temperature, filtering and drying to obtain the fluorescent-magnetic resonance bimodal contrast agent intermediate. Stirring, separating out, filtering and drying to obtain the refined fluorescent-magnetic resonance bimodal contrast agent intermediate. The crystallization method has a good refining effect and meets the industrial production requirements. # imgabs0 #

Description

Technical Field

[0001] The invention relates to the field of medical diagnostic imaging, and in particular to a crystallization method and application of a fluorescence-magnetic resonance dual-modality contrast agent intermediate. Background Art

[0002] With the continuous development of molecular imaging methods, dual-modal or multi-modal molecular probes that combine multiple imaging methods are favored by people. Such probes can be used for detection of different imaging devices at the same time, realizing the complementary advantages of multiple imaging modes, and can provide more comprehensive diagnostic information for complex diseases. Among them, the MRI / NIR dual-modal probe based on nuclear magnetic resonance imaging and near-infrared imaging has the characteristics of high spatial resolution of MRI, high sensitivity of NIR and rapid imaging. It can provide more accurate imaging information in the early diagnosis of malignant tumors and intraoperative fluorescence navigation applications, which is of great significance in medical diagnosis. The preparation of MRI / NIR dual-modal probes with high MRI relaxation rate, NIR fluorescence efficiency and tumor targeting recognition ability is becoming one of the research hotspots.

[0003] Patent CN115364245A discloses a novel fluorescence-magnetic resonance dual-modal contrast agent compound V with excellent performance and a preparation method thereof (the reaction formula is as follows, and the compound number is re-edited): compound IV and gadolinium chloride hydrate are dissolved in water, reacted at room temperature for 1-5 days, and purified by column to obtain intermediate compound I, and intermediate compound I and compound III are subjected to condensation reaction to prepare compound V. Among them, the preparation time of intermediate compound I is long, and it needs to be purified by column chromatography process, which is not conducive to industrial production.

[0004]

[0005] Therefore, there is an urgent need to develop an industrial preparation method suitable for the fluorescence-magnetic resonance dual-modal contrast agent intermediate compound I. Summary of the invention

[0006] In view of the problems existing in the prior art, the present invention aims to provide a crystallization method and application of a fluorescence-magnetic resonance dual-modality contrast agent intermediate.

[0007] In one aspect, the present invention provides a method for crystallizing a fluorescence-magnetic resonance dual-modality contrast agent intermediate, the crystallization method comprising the following steps:

[0008] S1: adding an alcohol solvent and water to the crude product of the fluorescence-magnetic resonance dual-modality contrast agent intermediate, heating and stirring to dissolve;

[0009] S2: then adding a nitrile solvent to the mixed solution obtained in step S1, cooling to room temperature, stirring to precipitate, filtering, and drying to obtain a refined fluorescence-magnetic resonance dual-modal contrast agent intermediate;

[0010] The structural formula of the fluorescence-magnetic resonance dual-modality contrast agent intermediate is shown in Formula I:

[0011]

[0012] Preferably, the alcohol solvent is one or more of methanol, ethanol, propanol and butanol.

[0013] Preferably, the nitrile solvent is one or more of acetonitrile, propionitrile, butyronitrile, isobutyronitrile or isopropionitrile.

[0014] Preferably, the combination of the nitrile solvent and the alcohol solvent is selected from: acetonitrile and ethanol, or acetonitrile and methanol, or propionitrile and ethanol, or isobutyronitrile and ethanol, or butyronitrile and ethanol, or isopropionitrile and ethanol, or acetonitrile and butanol, or acetonitrile and propanol.

[0015] Preferably, the nitrile solvent and the alcohol solvent are selected from acetonitrile and ethanol, respectively.

[0016] Preferably, the dissolution temperature in step S1 is 30-60°C, for example 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, etc.; preferably 40-50°C; the stirring time in step S2 is 10-20h, for example 10h, 11h, 12h, 13h, 14h, 15h, 16h, 17h, 18h, 19h, 20h, etc.; preferably 16-20h.

[0017] Preferably, the volume mass ratio of the alcohol solvent to the crude intermediate is 5-10 mL / g, preferably 5-8 mL / g, and further preferably 6-7 mL / g.

[0018] Preferably, the volume ratio of the alcohol solvent to water and the nitrile solvent is 1:(0.05-0.2):(1-5), preferably 1:(0.05-0.1):(2-3).

[0019] Another aspect of the present invention provides a method for preparing a fluorescence-magnetic resonance dual-modality contrast agent intermediate, the preparation method comprising the following steps:

[0020] S1: Compound II is complexed with a gadolinium reagent. After the complexation reaction is completed, the pH is adjusted to 7-9 with a base, the temperature is lowered to room temperature, and the mixture is filtered. The filtrate is subjected to nanofiltration and freeze-dried to obtain a crude intermediate compound I;

[0021] S2: the crude product obtained in step S1 is subjected to the above-mentioned crystallization method to obtain the refined intermediate compound I;

[0022] Wherein, the structure of the fluorescence-magnetic resonance dual-modality contrast agent intermediate is shown in Formula I, and the complexation reaction formula is as follows:

[0023]

[0024] Preferably, the gadolinium agent is a gadolinium salt or gadolinium oxide, the gadolinium salt includes gadolinium chloride and gadolinium acetate, and preferably the gadolinium is gadolinium oxide;

[0025] Preferably, the molar ratio of compound II to gadolinium reagent is 1:(0.4-1.0).

[0026] Preferably, the complex reaction solvent is water.

[0027] Preferably, the complexation reaction can be carried out at 80-100°C;

[0028] Preferably, the complexation reaction time is 40-80 min.

[0029] Preferably, the base includes but is not limited to sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, sodium acetate, and lithium hydroxide solution. The base is slowly added to the complex reaction system to adjust the pH, and the addition method is preferably dropwise addition.

[0030] The nanofiltration is a pressure-driven membrane separation process between reverse osmosis and ultrafiltration, and can separate and purify salts with low molecular weight and other water-soluble organic-inorganic materials by nanofiltration. Preferably, the nanofiltration equipment models that can be used include JM1812-1, 4040 or 8040, and the nanofiltration membrane models include PA-NF2-1812 and PA-NF-1812, NF-4040, or NF-8040.

[0031] Preferably, the conductivity of the filtrate after the nanofiltration is not higher than 100 μS / cm, and further preferably, the conductivity of the filtrate is not higher than 60 μS / cm.

[0032] Compared with the prior art, the present invention has the following beneficial effects: the fluorescence-magnetic resonance dual-modal contrast agent intermediate compound I obtained by the crystallization method of the present invention has high purity, good refining effect, and meets the needs of industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is the HPLC spectrum of the crude product prepared in Example 1.

[0034] Figure 2 This is the HPLC spectrum of the refined product prepared in Example 2. DETAILED DESCRIPTION

[0035] In order to better understand the technical solution of the present invention, the technical solution of the present invention is further described below in conjunction with specific embodiments. The embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0036] HPLC detection method for compound I: flow rate 1.0 mL / min, injection volume 10 μL, column temperature 35° C., chromatographic column Waters XSelect HSS PFP (4.6 mm×150 mm, 3.5 um), eluent A is 0.1% trifluoroacetic acid aqueous solution, eluent B is acetonitrile, and the mobile phase gradient is as follows:

[0037]

[0038] Example 1

[0039] Under nitrogen protection, 227.16g of compound II was added to 2736.0g of pure water, stirred to dissolve, 43.20g of gadolinium oxide was added, and the reaction was carried out at 100°C for 60min. After the reaction was completed, 1mol / L sodium hydroxide solution was slowly added dropwise to adjust the pH to 7-9. After the pH adjustment was completed, the reaction solution was cooled to room temperature and filtered. The filtrate containing compound I was desalted by nanofiltration until the filtrate conductivity was ≤60μS / cm. The desalted filtrate was lyophilized to obtain 167.76g of crude compound I with a chromatographic purity of 90.68%.

[0040] Example 2

[0041] Weigh 9.32g of the crude product prepared in Example 1, add 60mL of ethanol and 5mL of water, heat to 45°C, and stir to dissolve. After the solution is clear, slowly add 125mL of acetonitrile, cool to room temperature, and continue stirring and crystallizing for 16h. Filter, and dry the filter cake in vacuum at 50-60°C to obtain 7.00g of intermediate I compound, with a yield of 82.83% and a chromatographic purity of 97.70%.

[0042] Example 3

[0043] Weigh 9.32g of the crude product prepared in Example 1, add 60mL of ethanol and 5mL of water, heat to 45°C, and stir to dissolve. After the solution is clear, slowly add 125mL of propionitrile, cool to room temperature, and continue stirring and crystallizing for 16h. Filter, and vacuum dry the filter cake at 50-60°C to obtain 6.28g of intermediate I compound, with a yield of 74.31% and a chromatographic purity of 97.08%.

[0044] Example 4

[0045] Weigh 9.32g of the crude product prepared in Example 1, add 60mL of ethanol and 5mL of water, heat to 60°C, and stir to dissolve. After the solution is clear, slowly add 125mL of isobutyronitrile, cool to room temperature, and continue stirring and crystallizing for 16h. Filter, and dry the filter cake in vacuum at 50-60°C to obtain 6.03g of intermediate I compound, with a yield of 71.35% and a chromatographic purity of 96.93%.

[0046] Example 5

[0047] Weigh 9.32g of the crude product prepared in Example 1, add 60mL of ethanol and 5mL of water, heat to 30°C, and stir to dissolve. After the solution is clear, slowly add 125mL of butyronitrile, cool to room temperature, and continue stirring and crystallizing for 10h. Filter, and vacuum dry the filter cake at 50-60°C to obtain 6.01g of intermediate I compound, with a yield of 71.11% and a chromatographic purity of 96.88%.

[0048] Example 6

[0049] Weigh 9.32g of the crude product prepared in Example 1, add 60mL of ethanol and 5mL of water, heat to 45°C, and stir to dissolve. After the solution is clear, slowly add 125mL of isopropionitrile, cool to room temperature, and continue stirring and crystallizing for 20h. Filter, and dry the filter cake in vacuum at 50-60°C to obtain 6.33g of intermediate I compound, with a yield of 74.90% and a chromatographic purity of 97.01%.

[0050] Example 7

[0051] Weigh 9.32g of the crude product prepared in Example 1, add 60mL of methanol and 5mL of water, heat to 45°C, and stir to dissolve. After the solution is clear, slowly add 125mL of acetonitrile, cool to room temperature, and continue stirring and crystallizing for 16h. Filter, and dry the filter cake in vacuum at 50-60°C to obtain 6.06g of intermediate I compound, with a yield of 71.70% and a chromatographic purity of 97.26%.

[0052] Example 8

[0053] Weigh 9.32g of the crude product prepared in Example 1, add 60mL of propanol and 5mL of water, heat to 45°C, and stir to dissolve. After the solution is clear, slowly add 125mL of acetonitrile, cool to room temperature, and continue stirring and crystallizing for 16h. Filter, and dry the filter cake in vacuum at 50-60°C to obtain 6.20g of intermediate I compound, with a yield of 73.36% and a chromatographic purity of 96.71%.

[0054] Example 9

[0055] Weigh 9.32g of the crude product prepared in Example 1, add 60mL of butanol and 5mL of water, heat to 45°C, and stir to dissolve. After the solution is clear, slowly add 125mL of acetonitrile, cool to room temperature, and continue stirring and crystallizing for 16h. Filter, and dry the filter cake in vacuum at 50-60°C to obtain 6.17g of intermediate I compound, with a yield of 73.01% and a chromatographic purity of 96.15%.

[0056] Example 10

[0057] Weigh 9.32g of the crude product prepared in Example 1, add 90mL of ethanol and 5mL of water, heat to 45°C, and stir to dissolve. After the solution is clear, slowly add 125mL of acetonitrile, cool to room temperature, and continue stirring and crystallizing for 16h. Filter, and vacuum dry the filter cake at 50-60°C to obtain 6.10g of intermediate I compound, with a yield of 72.18% and a chromatographic purity of 97.45%.

[0058] Embodiment 11

[0059] Weigh 9.32g of the crude product prepared in Example 1, add 50mL of ethanol and 10mL of water, heat to 45°C, and stir to dissolve. After the solution is clear, slowly add 125mL of acetonitrile, cool to room temperature, and continue stirring and crystallizing for 16h. Filter, and vacuum dry the filter cake at 50-60°C to obtain 6.01g of intermediate I compound, with a yield of 71.11% and a chromatographic purity of 97.36%.

[0060] Example 12

[0061] Weigh 9.32g of the crude product prepared in Example 1, add 60mL of ethanol and 5mL of water, heat to 45°C, and stir to dissolve. After the solution is clear, slowly add 295mL of acetonitrile, cool to room temperature, and continue stirring and crystallizing for 16h. Filter, and dry the filter cake in vacuum at 50-60°C to obtain 7.11g of intermediate I compound, with a yield of 84.13% and a chromatographic purity of 95.21%.

[0062] Example 13

[0063] Under nitrogen protection, 14.56g of compound II was added to 152.0g of pure water, stirred to dissolve, 2.40g of gadolinium oxide was added, and the reaction was carried out at 80°C for 80min. After the reaction was completed, 1mol / L sodium hydroxide solution was slowly added dropwise to adjust the pH to 7-9. After the pH adjustment was completed, the reaction solution was cooled to room temperature and filtered. The filtrate containing compound I was desalted by nanofiltration until the filtrate conductivity was ≤60μS / cm. The desalted filtrate was lyophilized to obtain 9.14g of crude compound I with a chromatographic purity of 83.71%.

[0064] Add 60 mL of ethanol and 5 mL of water to the crude product, heat to 40°C, and stir to dissolve. After the solution is clear, slowly add 125 mL of acetonitrile, cool to room temperature, and continue stirring and crystallizing for 16 hours. Filter, and dry the filter cake in vacuum at 50-60°C to obtain 6.29 g of intermediate compound I, with a yield of 82.21% and a chromatographic purity of 97.53%.

[0065] Embodiment 14

[0066] Under nitrogen protection, 12.62g of compound II was added to 152.0g of pure water, stirred to dissolve, 2.40g of gadolinium oxide was added, and the reaction was carried out at 100°C for 40min. After the reaction was completed, 1mol / L sodium hydroxide solution was slowly added dropwise to adjust the pH to 7-9. After the pH adjustment was completed, the reaction solution was cooled to room temperature and filtered. The filtrate containing compound I was desalted by nanofiltration until the filtrate conductivity was ≤60μS / cm. The desalted filtrate was lyophilized to obtain 9.28g of crude compound I with a chromatographic purity of 89.12%.

[0067] Add 60 mL of ethanol and 5 mL of water to the crude product, heat to 40°C, and stir to dissolve. After the solution is clear, slowly add 125 mL of acetonitrile, cool to room temperature, and continue stirring and crystallizing for 16 hours. Filter, and dry the filter cake in vacuum at 50-60°C to obtain 6.72 g of intermediate compound I, with a yield of 81.25% and a chromatographic purity of 97.64%.

[0068] Embodiment 15

[0069] Under nitrogen protection, 6.01g of compound II was added to 152.0g of pure water, stirred to dissolve, 2.40g of gadolinium oxide was added, and the reaction was carried out at 100°C for 60min. After the reaction was completed, 1mol / L sodium hydroxide solution was slowly added dropwise to adjust the pH to 7-9. After the pH adjustment was completed, the reaction solution was cooled to room temperature and filtered. The filtrate containing compound I was desalted by nanofiltration until the filtrate conductivity was ≤60μS / cm. The desalted filtrate was lyophilized to obtain 9.36g of crude compound I with a chromatographic purity of 88.94%.

[0070] Add 60 mL of ethanol and 5 mL of water to the crude product, heat to 40°C, and stir to dissolve. After the solution is clear, slowly add 125 mL of acetonitrile, cool to room temperature, and continue stirring and crystallizing for 16 hours. Filter, and dry the filter cake in vacuum at 50-60°C to obtain 6.81 g of intermediate compound I, with a yield of 81.80% and a chromatographic purity of 97.58%.

[0071] Comparative Example 1

[0072] Weigh 9.32 g of the crude product prepared in Example 1, add 60 mL of ethanol, heat to 45° C., and stir to dissolve. After the solution is clear, slowly add 125 mL of acetonitrile, cool to room temperature, and continue stirring for 16 h. No solid precipitates.

[0073] Comparative Example 2

[0074] Weigh 9.32g of the crude product prepared in Example 1, add 60mL of dimethyl sulfoxide and 5mL of water, heat to 45°C, and stir to dissolve. After the solution is clear, slowly add 125mL of acetonitrile, cool to room temperature, and continue stirring and crystallizing for 16h. Filter, and vacuum dry the filter cake at 50-60°C to obtain 4.72g of intermediate I compound, with a yield of 55.85% and a chromatographic purity of 94.03%.

[0075] Comparative Example 3

[0076] Weigh 9.32g of the crude product prepared in Example 1, add 60mL of ethanol and 5mL of water, heat to 45°C, and stir to dissolve. After the solution is clear, slowly add 125mL of methyl tert-butyl ether, cool to room temperature, and continue stirring and crystallizing for 16h. Filter, and dry the filter cake in vacuum at 50-60°C to obtain 6.12g of intermediate I compound, with a yield of 72.41% and a chromatographic purity of 93.15%.

[0077] Comparative Example 4

[0078] Weigh 9.32g of the crude product prepared in Example 1, add 60mL of ethanol and 5mL of water, heat to 45°C, and stir to dissolve. After the solution is clear, slowly add 125mL of ethyl acetate, cool to room temperature, and continue stirring and crystallizing for 16h. Filter, and dry the filter cake in vacuum at 50-60°C to obtain 6.04g of intermediate I compound, with a yield of 71.47% and a chromatographic purity of 92.48%.

Claims

1. A method for crystallizing a fluorescence-magnetic resonance dual-modality contrast agent intermediate, characterized in that: The steps include: S1: adding an alcohol solvent and water to the crude product of the fluorescence-magnetic resonance dual-modality contrast agent intermediate, heating and stirring to dissolve; S2: then adding a nitrile solvent to the mixed solution obtained in step S1, cooling to room temperature, stirring to precipitate, filtering, and drying to obtain a refined fluorescence-magnetic resonance dual-modal contrast agent intermediate; Wherein, the structure of the fluorescence-magnetic resonance dual-modality contrast agent intermediate is as shown in Formula I:

2. The crystallization method according to claim 1, characterized in that The alcohol solvent is one or more of methanol, ethanol, propanol and butanol.

3. The crystallization method according to claim 1, characterized in that The nitrile solvent is one or more of acetonitrile, propionitrile, butyronitrile, isobutyronitrile or isopropionitrile.

4. The crystallization method according to claim 1, characterized in that The combination of the nitrile solvent and the alcohol solvent is selected from: acetonitrile and ethanol, or acetonitrile and methanol, or propionitrile and ethanol, or isobutyronitrile and ethanol, or butyronitrile and ethanol, or isopropionitrile and ethanol, or acetonitrile and butanol, or acetonitrile and propanol.

5. The crystallization method according to claim 1, characterized in that The nitrile solvent and the alcohol solvent are selected from acetonitrile and ethanol respectively.

6. The crystallization method according to claim 1, characterized in that The dissolving temperature in step S1 is 30-60° C.; the stirring time in step S2 is 10-20 h.

7. The crystallization method according to claim 1, characterized in that The volume mass ratio of the alcohol solvent to the intermediate crude product is 5-10 mL / g.

8. The crystallization method according to claim 1, characterized in that The volume ratio of the alcohol solvent to water and the nitrile solvent is 1:(0.05-0.2):(1-5).

9. A method for preparing a fluorescence-magnetic resonance dual-modality contrast agent intermediate, characterized in that: The steps include: S1: Compound II is complexed with a gadolinium reagent. After the complexation reaction is completed, the pH is adjusted to 7-9 with a base, the temperature is lowered to room temperature, and the mixture is filtered. The filtrate is subjected to nanofiltration and freeze-dried to obtain a crude intermediate compound I; S2: the crude product obtained in step S1 is subjected to a crystallization method according to any one of claims 1 to 8 to obtain a purified intermediate compound I; Wherein, the structure of the fluorescence-magnetic resonance dual-modality contrast agent intermediate is shown in Formula I, and the complexation reaction formula is as follows:

10. The preparation method according to claim 9, characterized in that: The gadolinium reagent is a gadolinium salt or gadolinium oxide, and the gadolinium salt includes gadolinium chloride and gadolinium acetate. Preferably, the gadolinium is gadolinium oxide; the molar ratio of the compound II to the gadolinium reagent is 1:(0.4-1.0).

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