Preparation method and application of benzothiazole acylhydrazone derivative

Abstract

A preparation method and application of a benzothiazole acylhydrazone derivative, relating to the field of analysis and detection, in particular to the field of continuous detection of zinc ions and glyphosate. The invention solves the problem that the compounds in the existing continuous detection methods of zinc ions and glyphosate have poor ability to resist multiple interference factors. The preparation method of the benzothiazole acylhydrazone derivative in the present invention is: the derivative is obtained by condensation reaction of benzothiazole-2-carboxylic acid hydrazone and 3,5-di-tert-butyl salicylaldehyde. The benzothiazole acylhydrazone derivative prepared by the present invention has a simple preparation method, can realize continuous detection of zinc ions and glyphosate in a neutral environment, and the detection process can resist interference from multiple metal ions and anions. The present invention does not require large equipment and complex operations, and can be used in the field of continuous detection of zinc ions and glyphosate.

Description

Technical Field

[0001] The invention relates to the field of analysis and detection, and in particular to a method for preparing a benzothiazole acylhydrazone derivative and application of the benzothiazole acylhydrazone derivative in continuous detection of zinc ions and glyphosate. Background Art

[0002] Benzothiazole, also known as 1,3-thiazolindene, is a class of heterocyclic compounds containing nitrogen and sulfur and having a conjugated system in the structure. Because its structure has a rigid plane and a large range of π conjugated system, it satisfies the Huckel rule and has aromaticity, which makes benzothiazole relatively stable and not easily oxidized, and it has gradually been used in the industrial field. At present, benzothiazole compounds are widely used in medicine, polymer materials, printing and dyeing industry, catalysis field and functional materials. Because it is easy to introduce heteroatoms containing lone pairs of electrons such as nitrogen, oxygen and sulfur into its structure, it is easy to coordinate and complex with metal ions to achieve the purpose of detecting metal ions, which makes benzothiazole derivatives also have important applications in the field of fluorescent probes. At present, the design, synthesis and application of benzothiazole fluorescent probes are also hot topics in scientific research.

[0003] Benzothiazole-2-carboxylic acid hydrazide is a class of derivatives of benzothiazole. The introduction of the 2-position hydrazide group provides a new reaction site and more oxygen and nitrogen heteroatoms. At present, the compound is widely used in the field of drug preparation, but it is rarely reported in the design of fluorescent probe molecules. Therefore, the present invention uses the 2-position hydrazide group as the reaction site and prepares a novel benzothiazole acylhydrazone derivative by condensation reaction with 3,5-di-tert-butyl salicylaldehyde. There are multiple oxygen atoms and nitrogen atoms in the structure of the derivative, which provide favorable binding sites for metal ions; at the same time, the introduction of the electron-donating group tert-butyl on the benzene ring makes it have better fluorescence properties, so the derivative can realize the fluorescence response recognition of zinc ions. In addition, based on the ligand replacement principle, it and the zinc ion complex can realize the tandem detection of glyphosate. The benzothiazole acylhydrazone derivative prepared by the present invention has multiple detection functions, excellent performance, can resist the interference of various factors, and has a better practical application prospect. Summary of the invention

[0004] The benzothiazole acylhydrazone derivative prepared by the invention can realize continuous detection of zinc ions and glyphosate under neutral conditions, has better performance, and can resist interference from various factors.

[0005] A benzothiazole acylhydrazone derivative prepared by the present invention has a molecular structure as follows:

[0006]

[0007] The synthetic route of the above derivatives is as follows:

[0008]

[0009] The invention discloses a method for preparing a benzothiazole acylhydrazone derivative. The method comprises the following steps: condensing benzothiazole-2-carboxylic acid hydrazone with 3,5-di-tert-butyl salicylaldehyde to obtain the derivative.

[0010] The method for continuously detecting zinc ions and glyphosate by using benzothiazole acylhydrazone derivatives of the present invention is as follows: the derivatives form a complex with zinc ions to cause a fluorescence enhancement effect, and glyphosate is added to the complex to cause a fluorescence quenching effect, thereby realizing continuous detection of zinc ions and glyphosate.

[0011] Preferably, the interfering ion in the process of detecting zinc ions can be Ag. + 、Co 2+ 、Al 3+ 、Bi 2+ , Ca 2+ 、Cd 2 + Cr 3+ , Cs 2+ , Hg 2+ , K + , Li + Mg 2+ , Ba 2+ , Fe 3+ 、Na + , Pb 2+ Cu 2+ One or more of.

[0012] Preferably, the interfering anion of the derivative and the zinc ion complex in the detection of glyphosate can be Cl - 、F - ,I - Br - 、CH3COO - 、S2O3 2- 、SO4 2- 、CO3 2- 、HCO3 - 、SO3 2- 、Cr2O7 2- 、NO2 - and P2O7 4- One or more of.

[0013] Principle of the present invention:

[0014] The benzothiazole acylhydrazone derivative prepared by the present invention has a large conjugated system in its structure and has multiple oxygen and nitrogen atoms. These heteroatoms are easy to complex with zinc ions and cause electronic shift to produce fluorescence enhancement effect. Based on the ligand replacement principle, the pesticide glyphosate can capture the zinc ions in the complex of the derivative and the zinc ion, free the derivative, and induce the fluorescence quenching effect, thereby realizing the continuous detection of zinc ions and glyphosate.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1) The present invention introduces benzothiazole-2-carboxylic acid hydrazide into the design of fluorescent probe molecular structure to develop new applications for benzothiazole derivatives.

[0017] 2) The present invention prepares a benzothiazole acylhydrazone derivative with dual detection function, which can realize continuous detection of zinc ions and glyphosate in a neutral environment and has application prospects in the field of biological detection.

[0018] 3) The benzothiazole acylhydrazone derivative prepared by the present invention has excellent performance and can resist interference from various factors in the process of continuous detection of zinc ions and glyphosate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The present invention prepares the derivative 1 H NMR spectrum;

[0020] Figure 2 IR spectra of the derivatives prepared by the present invention;

[0021] Figure 3 The selectivity of the derivatives in recognizing metal ions;

[0022] Figure 4 Anti-interference property of derivatives in recognizing zinc ions;

[0023] Figure 5 The linear relationship of the fluorescence response of the derivatives to different concentrations of zinc ions;

[0024] Figure 6 Job's plot of the derivatives to zinc ions;

[0025] Figure 7 Derivative-zinc ion complexes are selective for organophosphorus pesticides;

[0026] Figure 8 Derivative-zinc ion complex recognizes glyphosate's resistance to coexisting organophosphorus pesticide interference;

[0027] Fig. 9 The derivative-zinc ion complex recognizes glyphosate against the interference of coexisting anions;

[0028] Fig.10 Linear relationship diagram of the fluorescence response of the derivative-zinc ion complex to different concentrations of glyphosate;

[0029] Fig.11 Job's plot of the derivative-zinc ion complex to glyphosate; DETAILED DESCRIPTION

[0030] The technical solution of the present invention is not limited to the specific implementation modes listed below, but also includes any combination of the specific implementation modes.

[0031] Specific implementation method 1: In this implementation method, a benzothiazole acylhydrazone derivative has a molecular structure of:

[0032]

[0033] Specific implementation method 2: The preparation method of the derivative is: benzothiazole-2-carboxylic acid hydrazide and 3,5-di-tert-butyl salicylaldehyde are subjected to condensation reaction to obtain the derivative.

[0034] Specific implementation method three: Application of the derivative described in this implementation method in the continuous detection of zinc ions and glyphosate.

[0035] Specific implementation method four: This implementation method is different from specific implementation method three in that: the method for continuously detecting zinc ions and glyphosate using derivatives is: the derivatives form a complex with zinc ions to cause a fluorescence enhancement effect, and adding glyphosate to the complex causes a fluorescence quenching effect, thereby achieving continuous detection of zinc ions and glyphosate.

[0036] Specific embodiment 5: This embodiment is different from the specific embodiment 4 in that the interfering ion in the process of detecting zinc ions can be Ag. + 、Co 2+ 、Al 3+ 、Bi 2+ , Ca 2+ 、Cd 2+ Cr 3+ , Cs 2+ , Hg 2+ , K + , Li + Mg 2+ , Ba 2+ , Fe 3 + 、Na + , Pb 2+ Cu 2+ The rest is the same as the fourth embodiment.

[0037] Specific embodiment 6: This embodiment is different from specific embodiment 4 or 5 in that the interfering anion in the detection process of glyphosate can be Cl - 、F - ,I - Br - 、CH3COO - 、S2O3 2- 、SO4 2- 、CO3 2- 、HCO3 - 、SO3 2- 、Cr2O7 2- 、NO2 - and P2O7 4- The rest is the same as the fourth or fifth embodiment.

[0038] The embodiments of the present invention are described in detail below. The following embodiments are implemented on the premise of the technical solution of the present invention, and detailed implementation schemes and specific operation processes are given, but the protection scope of the present invention is not limited to the following embodiments.

[0039] Example 1: The preparation method of the benzothiazole acylhydrazone derivative of this example is carried out according to the following steps:

[0040] Accurately weigh benzothiazole-2-carboxylic acid hydrazide (1.5458 g, 0.008 mol) and 3,5-di-tert-butyl salicylaldehyde (1.9685 g, 0.0084 mol), respectively, and dissolve them in 2.5 mL of anhydrous ethanol. After complete dissolution, add the benzothiazole-2-carboxylic acid hydrazide solution to the 3,5-di-tert-butyl salicylaldehyde solution, heat to reflux, monitor the reaction, cool the system to room temperature, filter while hot, wash the filter cake with anhydrous ethanol 2-3 times, and dry to obtain a white solid, which is the derivative (2.7522 g, 0.0067 mol). Yield: 84%. 1 H NMR (300MHz, DMSO-d6) δ: 13.16 (s, 1H), 12.15 (s, 1H), 8.80 (s, 1H), 8.33-8.26 (m, 1H), 8.26 -8.20(m,1H),7.72-7.61(m,2H),7.36(d,J=2.4Hz,1H),7.19(d,J=2.3Hz,1H),1.42(s,9H),1.30(s,9H)ppm. FT-IR(KBr)v:3433.29, 3220.70, 2955.58, 2831.09, 1607.80, 1363.59, 1318.25, 1173.81, 1148.48, 774.57cm -1 .Derivatives 1H NMR spectrum and infrared spectrum are shown in Figure 1 , 2 shown.

[0041] Example 2: The derivatives of this example selectively recognize metal ions according to the following steps:

[0042] Take 3mL of 1.0×10 -5 mol / L derivative solution (V DMF :V 水 =95:5, HEPES 20mM, pH=7.4) in a cuvette, and then add 3eq. of Ag + 、Co 2+ 、Al 3+ 、Bi 2+ , Ca 2+ 、Cd 2+ Cr 3+ , Cs 2+ , Hg 2+ , K + , Li + Mg 2 + 、Zn 2+ , Ba 2+ , Fe 3+ 、Na + , Pb 2+ , Cu 2+ Under the action of 436nm excitation light, the peak intensity of fluorescence emission of the derivative at 557nm is measured. The results are as follows Figure 3 As shown in the figure, after zinc ions are added to the derivative solution, an obvious fluorescence enhancement effect is produced, which is enhanced by about 100 times, while the introduction of other metal ions fails to cause obvious fluorescence changes, indicating that the derivative exhibits a specific recognition effect on zinc ions.

[0043] Example 3: The anti-interference property of the derivatives in this example to recognize zinc ions was carried out according to the following steps:

[0044] Take 3 mL of the solution with a concentration of 1.0×10 -5 mol / L derivative solution, and 3 eq. of Ag was added successively + 、Co 2+ 、Al 3+ 、Bi 2 + , Ca 2+ 、Cd 2+ Cr 3+ , Cs 2+ , Hg 2+ , K + , Li + Mg2+ 、Zn 2+ , Ba 2+ , Fe 3+ 、Na + , Pb 2+ , Cu 2+ aqueous solution, and measure the fluorescence intensity. Then add 3eq. Zn 2+ The fluorescence intensity is observed and recorded. Figure 4 As shown in the figure, in Ag + 、Co 2+ Cu 2+ With Zn 2+ When coexisting, it can cause partial quenching of fluorescence intensity, but still show obvious fluorescence enhancement effect; other metal ions and Zn 2+ The coexistence of these two compounds had no significant effect on the fluorescence intensity. The derivatives had excellent anti-interference ability in the process of recognizing zinc ions.

[0045] Example 4: The fluorescence titration experiment of the derivatives of this example on zinc ions was carried out according to the following steps:

[0046] Take 3mL of the solution with a concentration of 1.0×10 -5 mol / L derivative solution, 1 μL of a concentration of 1×10 -2 mol / L zinc ion aqueous solution, and measure the fluorescence intensity. Plot the graph with zinc ion concentration as the horizontal axis and fluorescence intensity as the vertical axis. The results are as follows Figure 5 When the zinc ion concentration is within the range of 1μM-8μM, the fluorescence intensity increases with the increase of zinc ion concentration, and the fluorescence intensity and zinc ion concentration show a good linear relationship. The fitting equation is y=195.03x+36.00, R 2 =0.9946. According to the calculation formula of detection limit 3σ / k, the detection limit of the derivative for zinc ion is calculated to be 3.17×10 -8 mol / L. This derivatization can realize trace detection of zinc ions with high detection sensitivity.

[0047] Example 5: The complexation of the derivatives of this example with zinc ions is carried out according to the following steps:

[0048] The concentration is 1.0×10 -5 mol / L derivative solution and 1×10 -2 mol / L zinc ion aqueous solution, keeping the total concentration of probe and zinc ion in the system at 1×10 -8 mol / L remains unchanged. By changing the equivalent ratio of probe and zinc ion, the fluorescence intensity is measured and the Job's Plot curve is drawn. The results are shown in Figure 6As shown in the figure, Job's Plot shows that when the molar fraction of zinc ions is 0.53, the fluorescence intensity has an inflection point, which indicates that the complexation ratio between the derivative and zinc ions is 1:1.

[0049] Example 6: Selective recognition of organophosphorus pesticides by derivative-zinc ion complexes, carried out according to the following steps:

[0050] Take 3mL of the solution with a concentration of 1.0×10 -5 mol / L derivative solution was added with 1eq. of zinc ion solution, and the derivative-zinc ion system was obtained after incubation for 1 min. 3eq. of phosmet, dichlorvos, malathion, omethoate, dimethoate, ethoxychlor, fenitrothion, methyl parathion, parathion, glufosinate, trichlorfon and glyphosate were added in sequence, and the fluorescence intensity was measured under the action of 436nm excitation light. The results are as follows: Figure 7 When glyphosate was added, the fluorescence of the system was completely quenched, while when other pesticides were added, the fluorescence intensity did not change significantly, indicating that the derivative-zinc ion system achieved specific recognition of glyphosate.

[0051] Example 7: Derivative-zinc ion complex recognizes glyphosate's interference with coexisting organophosphorus pesticides, according to the following steps:

[0052] In the incubated derivative-zinc ion system, 3 eq. of phosmet, dichlorvos, malathion, omethoate, dimethoate, anthiophos, fenitrothion, methyl parathion, parathion, glufosinate, trichlorfon and glyphosate were added in sequence. Under the action of 436 nm excitation light, their fluorescence intensity was recorded. Then 3 eq. of glyphosate was added in sequence, and the change of fluorescence intensity was observed and recorded. The results are as follows: Figure 8 In the presence of other organophosphorus pesticides, the derivative-zinc ion system can still show complete fluorescence quenching in the recognition of glyphosate, indicating that the recognition process has good anti-interference ability.

[0053] Example 8: Derivative-zinc ion complex recognizes glyphosate's resistance to coexisting anion interference, according to the following steps:

[0054] Take 3mL of the solution with a concentration of 1.0×10 -5 mol / L derivative solution was added with 1eq. of zinc ion solution and incubated for 1 min to obtain the derivative-zinc ion system. 3eq. of Cl - 、F - ,I - Br - 、CH3COO - 、S2O3 2- 、SO4 2- 、CO3 2- 、HCO3 -、SO3 2- 、Cr2O7 2- 、NO2 - 、P2O7 4- The aqueous solution was exposed to 436 nm excitation light and its fluorescence intensity was recorded. Then 3 eq. of glyphosate were added in sequence and the changes in fluorescence intensity were observed and recorded. The results are shown in the figure. Fig. 9 As shown. Under the condition of the coexistence of interfering anions, the derivative-zinc ion system can still show complete fluorescence quenching phenomenon for glyphosate, indicating that the recognition process has good anti-interference ability.

[0055] Example 9: Fluorescence titration experiment of glyphosate by derivative-zinc ion complex was carried out according to the following steps:

[0056] In the incubated derivative-zinc ion system, 1 μL of the solution was added each time at a concentration of 1×10 -2 mol / L glyphosate aqueous solution, and measure the fluorescence intensity. The results are as follows Fig.10 When the glyphosate concentration is between 2 and 8 μM, the fluorescence intensity decreases with the increase of glyphosate concentration. The fluorescence intensity and glyphosate concentration show a good linear relationship. The fitting equation is y = -149.21x + 1465.95, R 2 =0.996. According to the calculation formula of detection limit 3σ / k, the detection limit of glyphosate by derivative-zinc ion system is calculated to be 8.56×10 -8 mol / L, the derivative-zinc ion system can realize trace detection of glyphosate with high sensitivity.

[0057] Example 10: The reaction of the derivative-zinc ion complex with glyphosate was carried out according to the following steps:

[0058] Maintain the total concentration of the derivative-zinc ion complex and glyphosate in the system at 1×10 -8 mol / L remains unchanged. By changing the equivalent ratio of the two, the fluorescence intensity is measured and the Job's Plot curve is drawn. The results are as follows Fig.11 When the molar fraction of glyphosate is 0.51, the fluorescence intensity has an inflection point, which indicates that the complexation ratio of the derivative-zinc ion complex and glyphosate is 1:1.

Claims

1. An application of a benzothiazole acylhydrazone derivative benzothiazole-2-carboxylic acid hydrazide 3,5-di-tert-butyl salicylaldehyde in the continuous detection of zinc ions and glyphosate, wherein the application is for non-disease diagnosis or treatment purposes.

2. The use according to claim 1, characterized in that The method for continuously detecting zinc ions and glyphosate by using derivatives is as follows: the derivatives form a complex with zinc ions to cause a fluorescence enhancement effect, and glyphosate is added to the complex to cause a fluorescence quenching effect, thereby achieving continuous detection of zinc ions and glyphosate.

3. The use of the derivative according to claim 2 in the continuous detection of zinc ions and glyphosate, characterized in that Derivatives can resist Ag in the detection of zinc ions + 、Co 2+ 、Al 3+ 、Bi 3+ , Ca 2+ 、Cd 2+ Cr 3+ , Cs + , Hg 2+ , K + , Li + Mg 2+ , Ba 2 + , Fe 3+ 、Na + , Pb 2+ Cu 2+ interference.

4. The use of the derivative according to claim 2 in the continuous detection of zinc ions and glyphosate, characterized in that The derivatives and zinc ion complexes can resist Cl in the detection of glyphosate - 、F - ,I - Br - 、CH3COO - 、S2O3 2- 、SO4 2- 、CO3 2- 、HCO3 - 、SO3 2- 、Cr2O7 2- 、NO2 - and P2O7 4- interference.

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