55 results about "Pyrylium salt" patented technology

Provided is a cosmetic containing ascorbic acid and / or a salt thereof, which has excellent stability and reduced irritation to the skin. The cosmetic according to the present invention contains ascorbic acid and / or a salt thereof, ultrapure water, and an antioxidant, and the salt of ascorbic acid is at least one selected from the group consisting of a trimethylamine salt, a triethylamine salt, a monoethanolamine salt, a triethanolamine salt, a pyridinium salt, an arginine salt, an ammonium salt, a sodium salt, a potassium salt, a calcium salt, a magnesium salt, and an aluminum salt of ascorbic acid. The antioxidant is glutathione or sodium pyrosulfite, the pH of the cosmetic material is adjusted to 5.0-7.0, and the dissolved oxygen content of the cosmetic material is 0-5 mg / L.

The invention provides a preparation method of trifluoromethanesulfonic acid ionic liquid. According to the preparation method, trifluoromethanesulfonic acid, pyrrole salt, pyridinium salt, pyrazine salt and the like are subjected to substitution reaction, static layering, organic phase water washing and organic phase drying to achieve the purpose of generating the trifluoromethanesulfonic acid ionic liquid. The prepared trifluoromethanesulfonic acid ionic liquid is high in purity, good in yield and suitable for large-scale industrial application. The method provided by the invention is green and environment-friendly, and does not use harsh reaction conditions and organic solutions; meanwhile, the cost is low, the yield is high, and the purity of a crude product can reach 99.95% or above after the crude product is purified; and the method has the advantages of less required equipment, small occupied area and low investment, and can realize industrial production.

The present application relates to the field of macromolecular compounds connected to the polymer of styrene or alkyl-substituted styrene, in particular to a LED-sensitive ketoxime ester type water-soluble photoinitiator based on styryl pyridine salt and its manufacturing method and application. The LED-sensitive ketoxime ester type water-soluble photoinitiator based on styryl pyridine salt is characterized in that: a styryl group is connected to a pyridine ring to form a diaryl ethylene structure, and a ketoxime ester is connected to the para position of the double bond on the benzene ring. The manufacturing method of the LED-sensitive ketoxime ester type water-soluble photoinitiator based on styryl pyridine salt is characterized in that: the reaction is carried out according to the reaction formula (a), (b), (c) and (d) in sequence. The present application has good light absorption performance and good matching with LED light source.

The invention provides a method for degrading a retired wind power blade material by using a composite solvent, and belongs to the technical field of solid waste recycling. The method comprises the following steps: physically crushing the retired wind power blade to obtain a sample; mixing the sample with an organic solvent and an ionic liquid for reaction; the ionic liquid is imidazole salt ionic liquid or pyridine salt ionic liquid. According to the method disclosed by the invention, the retired wind power blade material is degraded by adopting the ionic liquid-organic solvent, so that oligomer or micromolecular monomer substances which are easy to separate are generated, and different components are effectively separated. After the reaction is finished, a glass fiber, balsa wood and rigid foam mixed material can be recovered and obtained, the mixed material can be used as a filler, a thermosetting resin degradation product can be converted into a useful chemical product and has high utilization value, and a catalyst is easy to recycle and reuse.

The invention belongs to the technical field of organic synthesis, and relates to an electron donor-double receptor type fluorescent compound as well as a preparation method and application thereof, the electron donor-double receptor type fluorescent compound has the following structural formula: # imgabs0 #, R1 is at least one of the following functional groups: # imgabs1 # R2 is H,-CH3,-COOCH2CH3,-COOCH3 or-NO2; x1 is a halogen ion; the preparation method comprises the following steps: # imgabs2: mixing a compound as shown in a formula 2, a compound as shown in a formula 3 and organic alkali, and carrying out a Knoevenagel reaction to obtain the electron donor-double receptor type fluorescent compound. Compared with the prior art, the photosensitizer structure disclosed by the invention can efficiently generate active oxygen and shows an efficient photodynamic killing effect on methicillin-resistant staphylococcus aureus and escherichia coli. Due to the characteristics, the donor-double acceptor pyridinium salt derivative has important application value in the development of novel antibacterial materials.

The application provides a static spinning solution containing pyridinium propane sulfonate, a preparation method thereof and a static spinning method thereof. The static spinning solution comprises an additive pyridinium propane sulfonate, PAN polyacrylonitrile and DMF. Experiments prove that the static spinning solution has low cost, can improve the entanglement degree between molecular chains, inhibits the breakage of a solution jet in a static spinning process, and the micro-morphology is improved.

The invention relates to the technical field of biomedical detection and functional organic fluorescent materials, in particular to synthesis and application of a single-molecule probe combining BODIPY (boron dipyrromethene) and a semi-cyano dye. Comprising the following steps: preparing an intermediate 1: reacting 4-hydroxybenzaldehyde with 2, 4-dimethyl pyrrole to generate BDP-OMe, and then reacting with pyridinium chlorochromate to obtain the intermediate 1; preparation of an intermediate 2: carrying out reflux reaction on 2, 3, 3-trimethyl-3H-indole and 2-bromoethanol in ethanol to obtain the intermediate 2; and synthesizing a final product: heating the intermediate 1 and the intermediate 2 in toluene to react, and performing post-treatment and column chromatography purification to obtain the probe CyB-C. The bimodal detection capability enables the probe to simultaneously distinguish the microenvironment difference between normal cells and cancer cells and monitor diseases related to viscosity abnormity.

The invention discloses a chitosan bipyridine group acid-resistant adsorbent as well as a preparation method and application thereof, and belongs to the technical field of electroplating sludge treatment. According to the invention, chitosan is selected as a matrix, and grafting of amido and pyridyl is carried out on the basis of the matrix, so that the adsorbent containing amido and pyridyl is prepared, and the problems that hydroxyl and amido on a chitosan body are protonated in an acid solution, so that the ability of chelating metal cations is poor, and the adsorption effect is poor are solved. The heavy metal in the acid solution cannot be effectively separated. In addition, amido and a reagent 2-chloromethylpyridine hydrochloric acid (2-CPD) with lower price are used for substitution reaction, and compared with existing M4195 commercial resin, the production cost is reduced, and the preparation method is suitable for large-scale popularization and application.

The present application relates to a kind of hypochlorite detection probe based on pyridine salt and preparation method thereof.The fluorescence probe structure is as shown in formula I.The fluorescent molecular probe of the present application is prepared from o-alkynyl aldehyde as raw material, by condensation reaction with pyridine salt.The probe synthesis method is simple, and the reaction condition is mild, and the yield of target compound is high.The fluorescent molecular probe described in the present application has stable optical performance, high sensitivity for hypochlorite detection, low detection lower limit, detection limit is 0.38 μM, response range is 5-200 μM.It has good selectivity, and has no response to fluoride ion, iodine ion, perchlorate ion, bisulfate ion, sulfate ion, acetate ion, thiocyanate ion, sulfur ion, etc.The fluorescent molecular probe described in the present application has practical application value in the field of biochemistry and environmental chemistry, especially the detection of hypochlorite ion in water, etc.

The invention discloses a fireproof flame-retardant fiber and a preparation method thereof, and relates to the technical field of fibers. When the fireproof and flame-retardant fiber is prepared, luteolin and 3-chloro-1-propylene are subjected to a reaction, and modified luteolin is prepared; the modified luteolin and zinc acetate are subjected to a reaction, and a luteolin complex is prepared; the preparation method comprises the following steps: reacting pyridinium salt dimethyl pimelate, dimethyl terephthalate, 1, 6-hexanediol and dihydroxy DOPO (9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide) to obtain copolyester; acrylic acid is polymerized and coated on the surface of magnesium hydroxide to prepare modified magnesium hydroxide; and uniformly mixing the modified magnesium hydroxide, a luteolin complex and copolyester, carrying out melt spinning, and treating with azodiisobutyronitrile to obtain the fireproof flame-retardant fiber. The fireproof flame-retardant fiber prepared by the invention has excellent flame retardance, antibacterial property and mechanical strength.

The present invention discloses a temperature-responsive two-photon MOF-based fluorescent probe, its preparation method, and application, relating to the field of fluorescent probe technology. MOF-199 is used as a nanocarrier, simultaneously loaded with a photothermal agent, gold nanorods (Au NRs), and a temperature-responsive pyridinium salt molecule (B). MOF-199 can degrade in the acidic tumor microenvironment, and the released copper ions react with overexpressed H2O2 through a Fenton-like reaction to generate ·OH, inducing tumor cell apoptosis and achieving chemodynamic therapy. Au NRs, with high photothermal conversion efficiency, can achieve photothermal therapy under near-infrared light irradiation, and local hyperthermia can further accelerate ·OH generation, thereby accelerating the chemodynamic therapy process. B, with its two-photon response characteristics, can achieve real-time temperature monitoring under near-infrared light irradiation, and the coated phase change material film can effectively prevent B leakage, achieving temperature-controlled release.

The invention provides a high-voltage quick charge binder and a preparation method thereof, positive electrode slurry, a positive electrode plate and a battery, and relates to the field of binders. The high-voltage quick charge binder comprises poly (4-cyano-2-butenoic acid N-cyano-2-trifluoropropyl pyridinium salt), and a binding agent, the structural formula of the poly (4-cyano-2-butenoic acid N-cyano-2-trifluoropropyl pyridinium salt) is shown in the specification. The high-voltage quick charge binder can effectively improve the voltage window of the binder, so that the stability of a high-voltage positive electrode system is improved.

The application provides a monovalent ionic liquid fiber membrane, a preparation method and application in recovery of palladium, and belongs to the technical field of adsorbing materials, and comprises the following steps: mixing dichloromethane and acetic acid to obtain a first solution; dissolving cellulose acetate and ionic liquid in the first solution to obtain a second solution; the ionic liquid is any one of an alkenyl imidazole salt, a quaternary ammonium salt containing an alkenyl group, a quaternary phosphonium salt containing an alkenyl group, a pyridine salt containing an alkenyl group or a morpholine salt containing an alkenyl group; N,N'-methylene bisacrylamide and benzoyl peroxide are added into the second solution, heated, stirred and warmed to obtain a third solution, and the third solution is subjected to high-pressure electrospinning to obtain the monovalent ionic liquid fiber membrane; or the second solution is subjected to high-pressure electrospinning and then irradiation to obtain the monovalent ionic liquid fiber membrane. The monovalent ionic liquid fiber membrane prepared by the application can realize rapid adsorption and easy regeneration and desorption, and can efficiently and selectively adsorb and recover palladium from a complex acidic solution.

The application provides a light conversion agent, a preparation method and application thereof, and a light conversion film, and belongs to the technical field of chemical synthesis. The light conversion agent is an organic salt ion-rare earth Eu (III) anion type, is an ion pair type light conversion agent, has absorption of organic and inorganic complexes, has stronger ultraviolet absorption capacity, and is synthesized by introducing an electron-donating group N,N-dimethyl into a para position of a pyridine nitrogen and introducing a bromohexyl group to form a corresponding electron-withdrawing pyridine group to synthesize a pyridine salt, and is synthesized by taking 2-thiophene formyl trifluoroacetylacetone as a ligand to synthesize a rare earth anion complex Eu (HTTA) 4 ‑ By ion exchange, bromine ions in the pyridine salt are replaced by the complex anions, and by electrostatic interaction between the pyridine cation and the anion complex, sensitization of rare earth luminescence is realized, and the ultraviolet absorption capacity is improved. Moreover, the light conversion agent has a long alkyl flexible chain, can be better blended with LLDPE, and enhances the stability and dispersibility of the light conversion agent in resin.

The invention relates to an epsilon-alkyl alpha, beta-gamma, delta-diunsaturated ester compound, and belongs to the field of organic synthesis, the epsilon-alkyl alpha, beta-gamma, delta-diunsaturated ester compound has the following structural general formula: the compound structurally has multiple reaction sites, and has wide application in multiple fields due to reaction activity and structural diversity; a series of epsilon-alkyl alpha, beta-gamma, delta-diunsaturated ester compounds can be prepared by taking gamma-functionalized olefine aldehyde and pyridinium salt as starting raw materials under the synergistic catalysis of light and carbene, and a target compound can be subjected to certain chemical conversion; the compound can be used for synthesizing complex natural products, drug intermediates and the like as a dienophile in the fields of organic synthesis and fine chemical engineering. Besides, the substance also has wide application prospects in the aspects of polymer science and materials, and can be used as a comonomer to be used in the fields of coatings, adhesives, hydrogels and the like.

The alkyl pyridine salt compound disclosed by the invention has good nematicidal activity on Bursaphelenchus xylophilus and Meloidogyne incongnita, and the alkyl pyridine salt compound has the value of being further researched and developed into a nematicidal agent, and can be used for preparing the nematicidal agent. Compound with structural formula as follows: # imgabs0 #

The invention discloses a preparation method of a deuterated pyridinium salt participated photo-induced bicyclo [1.1. 1] pentane derivative, which comprises the following steps: putting a compound shown in a formula 1 and a compound shown in a formula 2 into an organic solvent, and carrying out illumination reaction on the compound shown in the formula 1 and the compound shown in the formula 2 and a bicyclo [1.1. 1] pentane compound shown in a formula 3 in an alkaline environment to obtain the deuterated pyridinium salt fragment-containing bicyclo [1.1. 1] pentane derivative shown in a formula 4, the reaction process is as follows: a substituent R1 is selected from an ester group or substituted amide, a substituent R2 is selected from phenyl or substituted phenyl, and the substituent of the substituted phenyl is methyl, methoxyl, cyano, an ester group, phenyl, halogen, tertiary butyl, phenoxyl, trifluoromethoxyl or trifluoromethyl. The method has the advantages of mild reaction conditions, no need of a catalyst, complete reaction at room temperature, economy, practicability, environmental friendliness and no generation of harmful substances; the efficiency is high after reaction amplification.

This patent application discloses a benzophenone-modified triphenylamine pyridinium salt organic photosensitizer, its preparation method, and its application. This photosensitizer is a triphenylamine-based compound, specifically synthesized into four compounds: CHO-TPAP-BP, CHO-pTPAP-BP, CHO-eTPAP-BP, and 2CN-eTPAP-BP. This organic photosensitizer combines the strong electron-withdrawing ability of pyridinium salts with the electron-donating properties of triphenylamine, resulting in greater separation of the HOMO-LUMO orbitals in the molecule. This is beneficial for reducing ΔE. ST Secondly, by utilizing the strong intersystem crossing ability of benzophenone, orbital spin coupling (SOC) can be enhanced, thereby increasing the efficiency of reactive oxygen species production and thus improving the photodynamic therapy effect; furthermore, it is hoped that anthracene and singlet oxygen ( 1 The characteristics of O2 reaction to generate internal peroxides and controllable release of oxygen under thermal conditions alleviate hypoxia during photodynamic therapy; at the same time, the multi-rotor structure and the multiple rotations and vibrations of bonds in the molecules are conducive to the construction of a photothermal conversion platform, thereby realizing multimodal synergistic therapy of tumors.

The invention provides a method for preparing 1, 2-disubstituted 1, 2-dihydro-3H-pyrazol-3-ketone, which comprises the following steps: by taking 1, 2-disubstituted pyrazol-3-ketone as an initial raw material, 1, 2-dichloroethane as a reaction solvent and pyridinium chlorochromate as an oxidizing agent, carrying out dehydroaromatization reaction on the 1, 2-disubstituted pyrazol-3-ketone to obtain the 1, 2-disubstituted 1, 2-dihydro-3H-pyrazol-3-ketone, and reacting the 1, 2-disubstituted 1, 2-dihydro-3H-pyrazol-3-ketone with 1, 2-dichloroethane to obtain the 1, 2-disubstituted 1, 2-dihydro-3H-pyrazol-3-ketone. The synthesis method comprises the following steps: preparing 1, 2-dihydro-3H-pyrazole-3-ketone. According to the present invention, the 1, 2-disubstituted 1, 2-dihydro-3H-pyrazole-3-ketone can be prepared, the reaction conditions are mild, the process is simple, the yield of the product 1, 2-disubstituted 1, 2-dihydro-3H-pyrazole-3-ketone is high, and the method is suitable for industrial production.

Chemical compounds that include a pyridinium-based compound functionalized by including a sulfur-containing substituent are provided. Also provided are materials and formulations including such pyridinium-based compounds. Also provided are corrosion-resistant substrates and films including such pyridinium-based compounds. Also provided are processes for inhibiting corrosion of a metallic surface using the formulations and processes of acidizing a subsurface formation using the pyridinium-based compounds.

A process for inhibiting microbial growth comprising administering a formulation comprising a pyridinium chloride compound of Formula (I), described herein, wherein R1-R6, independently comprise hydrogen, substituted or unsubstituted C1 to C24 alkyl, substituted or unsubstituted alkylaryl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, sulfonate, aryl sulfonate, C1 to C24 alkyl sulfonate, taurine, carboxylate, amine, alkylamine, arylamine, alkylammonium, arylammonium, sulfonamide, halogen, hydroxy, amide, nitro, cyano, azide, O-alkyl, S-alkyl, silyl, trialkylsilyl, O-silyl, haloalkyl, alkylsulfhydryl, trifluoromethyl, hydrazide, substituted or unsubstituted aryl, heteroaryl, or heterocyclic alkynyl, carboxyalkyl, aminoalkyl, haloalkyl, azidoalkyl, amide, amino acid, or peptide; and X and Y independently comprise a heteroatom selected from oxygen, nitrogen, or sulfur, or a heterocarbyl comprising one or heteroatoms selected from oxygen, nitrogen, or sulfur.

The invention discloses a pyridinium fluorescent probe compound as well as a preparation method and application thereof in cell mitochondrial staining, and belongs to the technical field of biomedical detection. The compound is formed by combining a 5-cyano indanone derivative and pyridinium salt, and the synthesis method is simple. The compound Y1OPy has large Stokes shift and low cytotoxicity, can specifically target living cell mitochondria, presents clear mitochondrial network structure fluorescence imaging, and does not have specific targeting to fixed cells, and the probe is suitable for real-time, dynamic and high-resolution fluorescence imaging of living cell mitochondria, and has wide application prospects. The method has a wide application prospect in the field of biomedical research.

The present invention discloses a photosensitizer based on a triphenylamine structure, its synthesis method and application, belonging to the technical field of small molecule photosensitizers. The present invention uses triphenylamine as an electron donor and pyridinium salt as an electron acceptor to synthesize a series of organic photosensitizers based on the triphenylamine structure. This organic photosensitizer is synthesized for the first time in the present invention, and this organic photosensitizer has the ability to quickly enter cells, rapidly generate ROS under white light irradiation, and can target mitochondria to efficiently kill tumor cells. At the same time, it can also induce the death of cancer cells by inducing the expression of apoptosis factors.

This invention discloses a pyran salt-catalyzed alcohol deoxygenation preparation method. 18 This invention relates to a method for labeling ketones with O, belonging to the field of organic synthesis technology. The process uses tertiary benzyl alcohol as a raw material and triphenylpyran salt as a catalyst, under visible light irradiation, with H2... 18 O is 18 O source, can be obtained in high yield 18 O-labeled ketones. This invention does not require acids or high temperatures, and avoids the residue of transition metals. It uses a novel, inexpensive organic photocatalyst to catalyze the oxidation of alcohols to ketones under mild reaction conditions. 18 O mark.

The application discloses an alkyl pyridine salt type aggregation-induced emission compound, a preparation method and application thereof, a molecular structural formula of the alkyl pyridine salt type aggregation-induced emission compound is as follows: the preparation method comprises the following steps: stirring and refluxing raw material D, 1,4-dimethyl pyridine-1-iodide, anhydrous ethanol and piperidine overnight, after the reaction mixture is cooled, vacuum concentration is carried out, and the crude product is purified by elution, so that the alkyl pyridine salt type aggregation-induced emission compound is obtained. The alkyl pyridine salt type aggregation-induced emission compound provided by the application can simultaneously and efficiently kill gram-positive bacteria and gram-negative bacteria.

The invention discloses a synthesis method of P-(1-ethoxyethoxy) styrene, which comprises the following steps: S1, reacting 4-acetoxystyrene with alkaline metal salt in an organic solvent system under the protection of inert gas, the reaction time in the S1 is 1-3 hours, the molar ratio of the 4-acetoxystyrene to the alkaline metal salt is 1: (2.2-2.8), and the reaction time in the S2 is 1-3 hours; adjusting the pH value of the reaction liquid, concentrating under reduced pressure, extracting and drying to obtain an intermediate p-hydroxystyrene; s2, in a mixed solvent system of dichloromethane containing a polymerization inhibitor and lower alcohol, p-hydroxystyrene and ethyl vinyl ether react under the catalytic action of pyridinium toluenesulfonate to obtain P-(1-ethyoxyl ethyoxyl) styrene; according to the present invention, the first step reaction is researched, the reaction condition is mild, the energy and the production cost are saved, the reaction time is short, the reaction process is simple, and the yield of the step is improved to be close to 100% so as to improve the total yield of the product.

The application discloses a kind of chitosan double pyridyl group acid-resistant adsorbents and its preparation method and application, belong to electroplating sludge processing technical field.The application selects chitosan as matrix, and carries out amine group and pyridyl group grafting on its basis, and the adsorbent containing amine group and pyridyl group is prepared, the problem that the hydroxyl group and amine group on chitosan body are protonated in acidic solution and the ability of chelating metal cation is poor is solved, and heavy metal in acidic solution cannot be effectively separated.The substitution reaction of amine group and the reagent 2-chloromethyl pyridine hydrochloride (2-CPD) with lower price is used in the application, compared with existing M4195 commercial resin, production cost is reduced, and it is suitable for wide range of popularization and application.

The invention discloses a method for preparing an ionic enamine compound from a pyridinium-alkyne monomer and application of the ionic enamine compound, belongs to the technical field of organic synthesis, and particularly relates to a method for preparing the ionic enamine compound by taking the pyridinium-alkyne monomer and an amine monomer as raw materials and carrying out alkyne-amine hydroamination reaction. The method can be carried out at room temperature without the action of a catalyst, the reaction efficiency is high, excellent regioselectivity and stereoselectivity are achieved, no by-product is generated in the reaction process, the atom economy is high, and the prepared ionic enamine compound contains ionic groups, is good in water solubility, contains heteroatoms and benzene rings in the structure, and can be used for preparing the ionic enamine compound. The compound has rich electrons, has a good application prospect in preparation of photodynamic drugs, photosensitizers, photodynamic antibacterial agents or biological imaging reagents, and can also be used as an effective synthon, that is, a nucleophilic reaction is further carried out, and compounds with more diversified structures are synthesized.

The invention provides a degradation agent for target protein degradation and a preparation method thereof, and relates to the field of target protein degradation. The degradation agent for target protein degradation is prepared from the following components in parts by weight: 1 to 2 parts of ZDHHC20 ligand, 1 to 2 parts of E3 ligase ligand, 2 to 4 parts of linker, 0.8 to 1.2 parts of halogenated hydrocarbon, 0.8 to 1.5 parts of Lewis acid, 1 to 2 parts of pyridinium chlorochromate, 2 to 3 parts of acetonitrile, 0.6 to 0.8 part of primary alcohol, 2 to 3 parts of alkali and 1 to 2 parts of aromatic compound. According to the degradation agent for target protein degradation provided by the invention, the pyridinium chlorochromate, the aromatic compound and the halogenated hydrocarbon are combined for use, so that basic chemical modification and comprehensive coverage of characteristics of a final product can be realized, firstly, carboxyl with relatively high activity is introduced through the pyridinium chlorochromate; the preparation method comprises the following steps: firstly, preparing the ZDHHC20, then improving the stability and targeting ability of molecules through an aromatic compound, finally completing a key chemical bond forming step by virtue of halogenated hydrocarbon and lewis acid, and indirectly recovering the functions of the cancer suppressor proteins and promoting cancer cells to enter an apoptosis procedure by degrading the ZDHHC20 or adjusting the activity of the ZDHHC20.

The invention discloses a polypeptide or protein modification method for photopromoting cysteine desulfurization, which comprises the following steps: by taking a naked peptide containing cysteine or a protein containing solvent-exposed cysteine as a raw material, taking a free radical receptor as another raw material, taking pyridinium as an activating reagent, taking a buffer solution as a reaction solvent, and carrying out photolysis reaction to obtain the polypeptide or protein. In the presence of a reducing agent and an additive and under the irradiation of visible light, cysteine desulfurization of polypeptide or protein is realized to form a stereoscopically retained C-X bond, and the free radical receptor is any one of electron-deficient olefin, acrylamide, acrylate, an organic selenium compound, 2, 2, 6, 6-tetramethylpiperidine-N-oxygen free radical or N-heterouracil. The invention relates to a method for constructing a C-X bond, which is promoted by visible light, stereoscopically retains a modification site and is compatible with a disulfide bond under a biocompatible condition, and can be used for site selective accurate modification of polypeptide and protein.