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CN-119504649-B - Benzothiadiazole type fluorescent probe for detecting HClO and preparation method thereof

CN119504649BCN 119504649 BCN119504649 BCN 119504649BCN-119504649-B

Abstract

The invention discloses a benzothiadiazole type fluorescent probe for detecting HClO and a preparation method thereof, belonging to the technical field of organic synthesis and HClO analysis. 4, 7-dibromo-2, 1,3 benzothiadiazole and p-formylphenylboric acid are used as raw materials, an intermediate B-CHO is obtained through Suzuki coupling, and then condensation reaction is carried out with hydroxylamine hydrochloride to prepare the hypochlorous acid fluorescent probe with high selectivity. The probe can rapidly and specifically identify HClO under the interference of common cations, anions, H 2 O 2 and biological mercaptan. The fluorescent organic small molecule BTD-OH has simple synthesis method, good thermal stability, strong fluorescence emission, large Stokes displacement (119 nm) and good stability, and can be stored as pure solid or solution at room temperature. The probe has the advantages of simple preparation, high yield, high response speed, low toxicity, high stability and specificity, and can be used as an effective hypochlorous acid detection tool in practical application.

Inventors

  • ZHOU PENGXIN
  • LIU JUNHAO
  • HUO SHUHUI
  • ZHANG XIAONAN
  • Qin Mengya

Assignees

  • 西北师范大学

Dates

Publication Date
20260512
Application Date
20241121

Claims (8)

  1. 1. A preparation method of a benzothiadiazole type fluorescent probe for detecting HClO is characterized by comprising the following steps: 。
  2. 2. The method for preparing a benzothiadiazole fluorescent probe for detecting HClO according to claim 1, characterized by comprising the steps of: (1) Dissolving 4, 7-dibromo-2, 1, 3-benzothiadiazole, 4-formylphenylboric acid, tetrakis (triphenylphosphine) palladium and potassium phosphate in a reaction solvent of ethanol and water, heating and refluxing under the protection of N 2 , cooling the system to room temperature after the reaction is finished, adding deionized water to quench the reaction, filtering and drying the reaction product, and purifying the reaction product by column chromatography to obtain a pale yellow solid B-CHO; (2) Adding intermediate B-CHO and hydroxylamine hydrochloride into a solvent, adding two drops of triethylamine, heating and refluxing, cooling the system fully after the reaction is finished, and carrying out suction filtration to obtain a pale yellow solid, and recrystallizing with dichloromethane to obtain a bright yellow solid BTD-OH.
  3. 3. The method for preparing a benzothiadiazole fluorescent probe for detecting HClO according to claim 2, wherein the molar ratio of 4, 7-dibromo-2, 1,3 benzothiadiazole to 4-formylphenylboronic acid in the step (1) is 1:2.5 to 1:3.
  4. 4. The method for preparing a benzothiadiazole fluorescent probe for detecting HClO according to claim 2, wherein the volume ratio of ethanol and water in the reaction solvent in the step (1) is 3:1.
  5. 5. The method for preparing a benzothiadiazole fluorescent probe for detecting HClO according to claim 2, wherein the reflux is conducted under the protection of N 2 -120 ℃ in the step (1) for 5-12 h.
  6. 6. The method for preparing a benzothiadiazole fluorescent probe for detecting HClO according to claim 2, wherein the molar ratio of the intermediate B-CHO to hydroxylamine hydrochloride in the step (2) is 1:2.5-1:3, and the solvent is absolute ethanol.
  7. 7. The method for preparing a benzothiadiazole fluorescent probe for detecting HClO according to claim 2, wherein two drops of triethylamine are added in the step (2), and the mixture is heated and refluxed at 30-80 ℃ for 8-12 h.
  8. 8. The use method of the benzothiadiazole type fluorescent probe for detecting HClO prepared by the preparation method according to any one of claims 1 to 7 comprises the following steps: (1) Adding absolute ethyl alcohol into the probe molecules to prepare a 20 mu M standard solution, adding a PBS buffer solution into the standard solution, adjusting the pH value to be 7.4, respectively adding HClO/ClO - solutions with different concentrations, standing for 1min, and performing fluorescence test to obtain a standard curve of hypochlorous acid concentration and fluorescence intensity; (2) And adding a PBS buffer solution into the standard solution, adjusting the pH value to be 7.4, adding the solution to be detected, standing for 1min, performing fluorescence test, and bringing the fluorescence intensity of the solution to be detected into a standard curve to obtain the hypochlorous acid concentration in the solution to be detected.

Description

Benzothiadiazole type fluorescent probe for detecting HClO and preparation method thereof Technical Field The invention relates to the technical field of organic synthesis and HClO analysis, in particular to a benzothiadiazole type fluorescent probe for detecting HClO and a preparation method thereof. Background The detection of hypochlorous acid by using the organic micromolecular probe has the advantages of simple synthesis, high sensitivity, rapid response, high selectivity, high space-time resolution and the like, and becomes an ideal tool for detecting analytes in biological systems and water environments. The structure based on pi-extended Benzothiadiazole (BTD) is stable, the electron-deficient structure is very important for planning the structure with high efficiency and stability, the BTD derivative usually has large Stokes shift so as to avoid unnecessary background interference, the BTD derivative usually does not fade under long-time irradiation, most fluorescent small molecule BTD derivatives can transpose cell membranes, can be used for detecting biological cells, can emit brightly, but has no obvious flicker to naked eyes, can obtain good signal-to-noise ratio, and most fluorescent small molecule BTD derivatives can be excited in a visible light area and can be stored as pure solid or solution at room temperature. More and more people begin to pay attention to the use of disinfectants, and the selection and use of disinfectant is also an important concern for people throughout the country. Hypochlorous acid is a Reactive Oxygen Species (ROS), is a powerful bleaching agent in daily life, is a main antibacterial agent in many biological and pathological processes, and has the advantages of high sterilization speed and strong sterilization power. However, abnormal changes in its concentration levels may cause a number of more serious diseases such as parkinsonism, atherosclerosis, cardiovascular diseases, lung injuries, rheumatoid arthritis and even some cancers. And excessive use of the disinfectant containing hypochlorous acid can cause the increase of chlorine-containing compounds in the water environment, thereby causing potential harm to organisms in the water environment. Therefore, the detection of hypochlorous acid is of great importance. Disclosure of Invention The invention aims to provide a preparation method of a benzothiadiazole type fluorescent small molecule, which has the advantages of simple synthesis, mild reaction conditions and low cost. It can be used for detecting HClO with high sensitivity and high selectivity. In order to achieve the above object, the present invention adopts the following scheme A benzothiadiazole fluorescent probe for detecting HClO, the structural formula is shown as follows: The preparation method of the BTD-OH comprises the following steps: Specifically, the preparation method of the probe molecule for detecting HClO specifically comprises the following steps: (1) Dissolving 4, 7-dibromo-2, 1, 3-benzothiadiazole, 4-formylphenylboric acid, tetrakis (triphenylphosphine) palladium and potassium phosphate in a reaction solvent of ethanol and water, heating and refluxing under the protection of N 2, cooling the system to room temperature after the reaction is finished, adding deionized water to quench the reaction, filtering and drying the reaction product, and purifying the reaction product by column chromatography to obtain a pale yellow solid B-CHO; (2) Adding intermediate B-CHO and hydroxylamine hydrochloride into a solvent, adding two drops of triethylamine, heating and refluxing, cooling the system fully after the reaction is finished, and carrying out suction filtration to obtain a pale yellow solid, and recrystallizing with dichloromethane to obtain a bright yellow solid BTD-OH. The molar ratio of the 4, 7-dibromo-2, 1, 3-benzothiadiazole to the 4-formylphenylboronic acid in the step (1) is 1:2.5-1:3. The molar ratio of 4, 7-dibromo-2, 1,3 benzothiadiazole, tetrakis (triphenylphosphine) palladium to potassium phosphate was 1:0.02:3. The volume ratio of ethanol to water in the reaction solvent in the step (1) is 3:1. And (3) refluxing for 5-12h at 80-120 ℃ under the protection of N 2 in the step (1). The molar ratio of the intermediate B-CHO and hydroxylamine hydrochloride in the step (2) is 1:2.5-1:3. The solvent in the step (2) is absolute ethyl alcohol. In the step (2), two drops of triethylamine are added, and the mixture is heated and refluxed for 8 to 12 hours at the temperature of 30 to 80 ℃. The using method of the benzothiadiazole type fluorescent probe for detecting HClO comprises the following steps: (1) Adding absolute ethyl alcohol into the probe molecules to prepare a 20 mu M standard solution, adding a PBS buffer solution into the standard solution, adjusting the pH value to be 7.4, respectively adding HC10/C10 - solutions with different concentrations, standing for 1min, and performing fluorescence test to obtain a standard curve o