This product is used as a polymerization inhibitor for styrene and polystyrene, and is also used for the preparation of metal colloidal solutions, shadow agents for film films, medicines and dyes. It is used as an oxygen absorber in gas analysis, and is used in cosmetic powders, hair conditioners, hair dyes, etc.
1. Application in Analysis The study found that pentavalent vanadium and Pyrogallol can form colored complexes in acetic acid buffer solution with pH value of 6.6, and the complexes can be adsorbed by anion exchange resin. On this basis, a method for the determination of vanadium by resin phase spectrophotometry was established. The relative standard deviation (RSD) (n = 5) of the assay results was less than 3%, and the recoveries ranged from 98.6% to 102.6%. When using liquid chlorine to synthesize hydrochloric acid, the lamp cap, sight glass short section and air cooling pipe of the hydrochloric acid synthesis furnace are seriously corroded. Analysis and research on liquid chlorine tail gas showed that it was caused by excessive oxygen content. During the analysis, potassium pyrogallate was used to determine the oxygen in the exhaust gas after sodium hydroxide absorption, and the maximum volume ratio of oxygen content could reach 20%. This helps a lot with antiseptics. The content of vitamin A, D3 and E in feed additives was determined simultaneously by filling nitrogen gas and leaving saponification overnight. Antioxidant Pyrogallol, ethanol and potassium hydroxide solution were added to the sample, then filled with nitrogen, placed under sealed and protected from light conditions for 24h for sufficient saponification, and then purified by high performance liquid chromatography for analysis. The method has the advantages of high recovery rate, good repeatability, accurate and reliable results, and relatively simple.
2. Applications in Synthesis The research uses Pyrogallol as raw material, which undergoes methyl etherification and Claisen rearrangement. The natural compound diarylbutane lignin was successfully synthesized by hydrogen iodide addition and Wurtz reaction, which was isolated from the stem of Porlieria Chilensis in Chile. substance. From the structure of Pyrogallol, it can be seen that it contains three electron-donating groups hydroxyl groups, which enhances the activity of the benzene ring and is easily acylated by an acylating agent. It is mainly used to synthesize polyhydroxybenzophenone products, which are an important class of organic intermediates and are widely used in plastics, resins, coatings, synthetic rubber, photosensitive materials, food, medicine and cosmetics. The application field and scope are also expanding, and the market demand is increasing rapidly. The representative products of polyhydroxybenzophenones that can be synthesized from pyrogallic acid are 2,3,4,4′-tetrahydroxybenzophenone, 2,3,4-trihydroxybenzophenone, Nanjing Longyuan Natural The polyphenol synthesis plant has industrialized the production of this product. Using Pyrogallol, monochloroethanol and sodium hydroxide as raw materials, using chloroform as solvent, and using ammonium tributylethyl sulfate as phase transfer catalyst, 1,2,3-tricarboxymethoxyl was synthesized benzene. The product is an excellent color developer with good selectivity. At present, the chemical products produced by Nanjing Longyuan Natural Polyphenol Synthesis Factory using Pyrogallol as raw materials include 1,2,3-trimethoxybenzene, 2,3,4-trimethoxybenzaldehyde, 2,3, 4-Trihydroxybenzaldehyde and other products. 2,3,4-Trimethoxybenzaldehyde is an important intermediate for the synthesis of lomerizine and other drugs for the treatment of cardiovascular diseases; 2,3,4-trihydroxybenzaldehyde is used for the synthesis of Parkinson’s syndrome An important intermediate of benserazide.
3. Applied medicine in medicine Pyrogallol is a strong reducing agent and has fungicidal effect. It is often formulated into ointment for the treatment of psoriasis, lupus vulgaris, various ringworms and other parasitic skin diseases. It is often made into 2% to 3%. Topical preparations for topical application. The adverse reaction is that a large area of skin or skin peeling surface is easily absorbed and poisoned, causing systemic poisoning. It is toxic to the kidneys and blood system, which can cause red blood cells to rupture, and a large amount of denatured hemoglobin is formed, and protein, red blood cells and casts appear in the urine. It is irritating to local skin and mucous membranes, and can be dyed brown after skin contact. When used, it should not be applied to large areas of skin and skin peeling surfaces to avoid absorption and poisoning. Not compatible with alkalis, heavy metal salts and oxidants.
4. Application in feed Pyrogallic acid has a significant effect on the feeding and growth and development of small silkworms, especially on the silkworm emergence rate and developmental uniformity of the third instar silkworm. After the oxygen in the atmosphere comes into contact with the feed, the fat, VA, VD, VE, VB, carotene, some amino acids, and proteins in the feed will be destroyed by oxygen to varying degrees, and trace amounts of copper, iron, zinc, and manganese in the feed will be destroyed. Elements will also accelerate oxidative rancidity, which will bring serious harm to the quality, nutritional value and safety of feed. The combination of citric acid, vitamin C and pyrogallic acid has strong antioxidant effect, has obvious growth-promoting effect on animals, is cheap, has no toxic side effects, and has great use value in feed.
5. Application in pesticides Rotenone is an insecticidal active substance extracted and isolated from Roten vines. It has excellent contact and stomach poisoning effects on pests, no pollution to the environment, and pests are not easy to develop resistance. It is an excellent insecticide. However, its efficacy is easily affected by environmental factors, is unstable in nature, and is prone to oxidative degradation and photolysis. The study found that using pyrogallic acid as an antioxidant and photoprotectant can prevent its degradation and prolong its efficacy, and the degradation rate is inversely proportional to the amount of Pyrogallol. It solves the problem that rotenone is unstable in the environment. Pyrogallol was reacted with 2,2-dimethylpropane, and then reacted with methyl isocyanate to prepare carboxycarb, and the total yield was 68%. Carbamate is a kind of carbamate heterocyclic insecticide which is used in health and agricultural production. It is a new variety of high-efficiency and low-residue pesticides. Resource pyrogallic acid, the process has high economic and social benefits.
6. Other applications The application of pyrogallic acid in other fields has also been reported. For example, Pyrogallol can be used as a raw material to synthesize liquid crystal ligands and some new imaging materials, and it is widely used as a flotation agent in metallurgy.