Tryptamine-Structure-Based Coumarin Fluorescent Reagent, Preparation Method Thereof and Application Thereof

Abstract

The present invention belongs to the field of chemical analysis and testing, and specifically relates to a coumarin fluorescent reagent based on a tryptamine structure, and a preparation method and application thereof. Using dichloromethane as a solvent, 7-(diethylamino)coumarin-3-formic acid and tryptamine as raw materials, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDCI) and 1-hydroxybenzotriazole (HOBT) as condensing agents, a room temperature reaction is performed to obtain a crude product. The crude product is then separated by thin layer chromatography using dichloromethane and methanol as developing agents to obtain a final yellow pure product. The fluorescent reagent obtained by the present invention has good optical properties and is 2+ With the participation of , fluorescence detection of tributyl phosphate can be achieved.

Description

Technical Field

[0001] The invention belongs to the field of chemical analysis and testing, and particularly relates to a coumarin fluorescent reagent based on a tryptamine structure, and a preparation method and application thereof. Background Art

[0002] Organophosphorus compounds are compounds containing carbon-phosphorus bonds or phosphate derivatives containing organic groups. They are a class of non-specific irreversible protease inhibitors and can be used as organophosphorus nerve gases, organophosphorus insecticides or herbicides, chemotherapeutic agents, plasticizers, antioxidants, surfactants, flame retardants, etc.

[0003] While these compounds are used across various industries, they also pose a threat to the public environment and human health. As the use of organophosphates increases year by year, environmental pollution becomes increasingly serious. Monitoring of typical crops, agricultural land, and rivers, such as those in rice-shrimp farming areas, tea plantations, and the Pearl River region, has detected the presence of organophosphates. Detection of tributyl phosphate (TBP), a plasticizer, is also essential.

[0004]

[0005] Formula 1-1 tributyl phosphate structural formula

[0006] Traditional detection methods include enzymatic chemical biosensors, Raman spectroscopy, and gas chromatography-mass spectrometry. However, these methods suffer from expensive equipment and complex operations. Among the many analytical methods, fluorescence analysis offers advantages such as simplicity, high selectivity, and high sensitivity, making it one of the most widely used analytical methods. Summary of the Invention

[0007] The present invention provides a fluorescent reagent H3 for detecting tributyl phosphate. The fluorescent reagent is a coumarin fluorescent reagent based on a tryptamine structure, and its structural formula is:

[0008]

[0009] The present invention also provides a specific preparation method of a fluorescent reagent for detecting tributyl phosphate: the chemical reaction formula for preparing the fluorescent reagent is:

[0010]

[0011] The specific operation steps are as follows: 7-(diethylamino)coumarin-3-carboxylic acid and tryptamine are first added to a dichloromethane solution in a molar equivalent of 1:1 to 1.5, and then 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDCI) and 1-hydroxybenzotriazole (HOBT) are added in an equivalent ratio of 2:2. The mixture is stirred at room temperature and reacted for 8 to 10 hours. Finally, the yellow fluorescent reagent H3 is purified by thin layer chromatography using a mixed solvent of dichloromethane and methanol in a volume ratio of 60:1 as a developing solvent to obtain the yellow fluorescent reagent H3.

[0012] The present invention also provides an application of the above fluorescent reagent: the prepared coumarin fluorescent reagent based on tryptamine structure is exposed to Cd 2+ The method was applied to the detection of tributyl phosphate in a mixed solution of Tris-HCl, MeCN and SDBS (volume ratio of 6-18:1:1).

[0013] In the structure of the compound of the present invention, 7-(diethylamino)coumarin-3-carboxylic acid serves as a fluorophore, and tryptamine serves as a ligand, connected by an amide bond. Tryptamine is an important biogenic amine with multiple pharmacological activities. Furthermore, it is an excellent ligand that can coordinate with chromium ions to form a complex. This complex then binds to tributyl phosphate (TBP), causing a change in fluorescence, thereby achieving the purpose of identifying tributyl phosphate.

[0014] The present invention solves the problem of selective recognition of tributyl phosphate (TBP) by metal ion complexes. From the reaction phenomenon, after adding tributyl phosphate, recognition is achieved by the change of enhanced fluorescence of the complex solution.

[0015] The beneficial effects of the present invention are: the raw materials of the present invention are easy to obtain, the synthesis method is simple, the reaction conditions are easy to control, and the product can be obtained through simple post-treatment after the reaction is completed; the detection of tributyl phosphate is convenient and the stability is good. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is the fluorescence spectrum of the fluorescent reagent prepared in Example 1 with the participation of different ions.

[0017] Figure 2 The fluorescent reagent prepared in Example 1 and Cd 2+ Fluorescence intensity diagram of the complex before and after reaction with tributyl phosphate (TBP) in different solvents.

[0018] Figure 3 The fluorescent reagent prepared in Example 1 is Cd 2+ Fluorescence spectra before and after the action of tributyl phosphate (TBP) in the presence of β-actin.

[0019] Figure 4The fluorescent reagent prepared in Example 1 and Cd 2+ The fluorescence changes over time after the complex reacts with tributyl phosphate (TBP).

[0020] Figure 5 This is the H NMR spectrum of the fluorescent reagent prepared in Example 1. DETAILED DESCRIPTION

[0021] The present invention is further described in detail below in conjunction with the embodiments:

[0022] Example 1

[0023] 7-(Diethylamino)coumarin-3-carboxylic acid (125.1 mg, 0.479 mmol) and tryptamine (76.6 mg, 0.479 mmol) were dissolved in 10 mL of dichloromethane, and condensing agent 1-hydroxybenzotriazole (129.3 mg, 0.958 mmol) and 1-ethyl-(3-dimethylaminoaldehyde)carbodiimide hydrochloride (182.9 mg,

[0024] The reaction mixture was stirred at room temperature for 8 hours. After the reaction was completed, the solvent was removed under reduced pressure and the product was analyzed by thin layer chromatography.

[0025] (DCM: MeOH = 60: 1) to give a yellow solid (83.0 mg, 43% yield)

[0026] The specific application method is: add 2 μL of 10 mM ion solution (the ions are K + 、Zn 2+ 、Li + 、Fe 3+ 、Hg 2+ 、Cd 2+ 、Fe 2+ 、Ag + 、Co 2+ 、Na + , Ca 2+ )( Figure 1 ), 196 μL of a mixed solution of Tris-HCl, MeCN, and SDBS (volume ratio of 18:1:1) and 2 μL of 2 mM H3, while an unionized H3 solution was used as a blank control. The solutions in each well were mixed evenly, and the fluorescence intensity of the solution in each well was measured. 2 μL of 10 mM tributyl phosphate (TBP) was then added to each well plate, the solutions were mixed evenly, and the fluorescence intensity of the solution in each well was measured. The results showed that: 2+ The fluorescence of the fluorescent reagent that formed a complex was enhanced after adding TBP compared with other groups.

[0027] Figure 1The fluorescence spectra of the fluorescent reagent prepared in Example 1 under the participation of different ions are shown in the figure. In the figure, after the different metal ions reacted with H3, there was no significant difference in fluorescence intensity between the sample groups and the control group.

[0028] Figure 2 The fluorescent reagent prepared in Example 1 and Cd 2+ Figure 2 shows the fluorescence intensity of the complex before and after interaction with tributyl phosphate (TBP) in different solvents. Compared with the other groups, the fluorescence of the complex was significantly enhanced in a mixed solvent of Tris-HCl, MeCN, and SDBS (volume ratio of 18:1:1) after the addition of TBP.

[0029] A mixed solvent of Tris-HCl, MeCN, and SDBS (volume ratio of 18:1:1) was the preferred solvent for H3 detection of TBP.

[0030] Figure 3 The fluorescent reagent H3 prepared in Example 1 is 2+ Fluorescence spectra of the fluorescent reagent before and after interaction with tributyl phosphate (TBP) with the presence of a metal ion. The figure shows that the fluorescence intensity of the fluorescent reagent remains unchanged after the addition of the metal ion to form a complex. However, upon the addition of TBP, the fluorescence intensity of the mixed solution at 460 nm increases, demonstrating the selective fluorescent recognition of TBP by the metal ion complex.

[0031] Figure 4 The fluorescent reagent prepared in Example 1 and Cd 2+ The fluorescence intensity of the complex gradually increases over time after the addition of TBP. The fluorescence reaches a maximum at 100 minutes and remains stable for 40 minutes.

[0032] Figure 5 This is the hydrogen spectrum of the fluorescent reagent H3 prepared in Example 1. 1H NMR (300MHz, DMSO-d6) δ10.86(d,J=2.4Hz,1H),8.77(t,J=5.7Hz,1H),8.68(s,1H),7.68(d ,J=9.0Hz,1H),7.61(d,J=8.1Hz,1H),7.35(d,J=8.0Hz,1H),7.20(d,J=2.3Hz,1H),7.11–7. 04(m,1H),6.98(ddd,J=7.9,6.9,1.0Hz,1H),6.79(dd,J=9.0,2.4Hz,1H),6.59(d,J=2.3Hz, 1H),3.67–3.58(m,2H),3.47(q,J=7.0Hz,4H),2.95(t,J=7.1Hz,2H),1.13(t,J=7.0Hz,6H).

[0033] Example 2

[0034] 7-(Diethylamino)coumarin-3-carboxylic acid (126.2 mg, 0.479 mmol) and tryptamine (91.9 mg, 0.575 mmol) were dissolved in 10 mL of dichloromethane, and condensing agent 1-hydroxybenzotriazole (130.1 mg, 0.958 mmol) and 1-ethyl-(3-dimethylaminoaldehyde)carbodiimide hydrochloride (180.1 mg,

[0035] The mixture was stirred at room temperature for 8 hours. After the reaction, the solvent was removed under reduced pressure and purified by thin layer chromatography (DCM:MeOH=60:1) to obtain a yellow solid (92.6 mg, yield 48%).

[0036] Example 3

[0037] 7-(Diethylamino)coumarin-3-carboxylic acid (201.3 mg, 0.766 mmol) and tryptamine (184.2 mg, 1.15 mmol) were dissolved in 10 mL of dichloromethane, and condensing agent 1-hydroxybenzotriazole (206.8 mg, 1.532 mmol) and 1-ethyl-(3-dimethylaminoaldehyde)carbodiimide hydrochloride (292.6 mg,

[0038] The mixture was stirred at room temperature for 10 hours. After the reaction, the solvent was removed under reduced pressure and the product was purified by thin-layer chromatography (DCM:MeOH=60:1) to give a yellow solid (159.3 mg, yield 52%).

Claims

1. An application of a coumarin fluorescent reagent based on a tryptamine structure, characterized in that: The fluorescent reagent is used to 2+ In the presence of a fluorescent agent, tributyl phosphate is detected in a mixed solution; wherein the mixed solvent is a mixed solvent of Tris-HCl, MeCN and SDBS in a volume ratio of 6-18:1:1; The structural formula of the fluorescent reagent is:

2. A method for preparing a tryptamine-based coumarin fluorescent reagent according to claim 1, characterized in that: The preparation method comprises the following steps: using dichloromethane as a solvent, dissolving 7-(diethylamino)coumarin-3-carboxylic acid and tryptamine in a round-bottom flask, then sequentially adding 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDCI) and 1-hydroxybenzotriazole (HOBT), stirring at room temperature, and obtaining a crude product after the reaction is completed; and finally purifying the product by thin-layer chromatography using dichloromethane and methanol as developing solvents to obtain a yellow final product, a coumarin fluorescent reagent based on a tryptamine structure.

3. The method for preparing the fluorescent reagent according to claim 2, wherein: The molar equivalent ratio of the 7-(diethylamino)coumarin-3-carboxylic acid, tryptamine, 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride EDCI and 1-hydroxybenzotriazole HOBT is 1:1 to 1.5:2:

2.

4. The method for preparing a fluorescent reagent according to claim 2, wherein: The reaction time at room temperature is 8 to 10 hours.

5. The method for preparing the fluorescent reagent according to claim 2, wherein: The developing solvent during the purification is a mixed solvent of dichloromethane and methanol in a volume ratio of 60:1.

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