Name | 3,4-Dihydroxybenzoic acid |
Synonyms | AKOS 220-70 Hypogallic acid Protocatechuic aci RARECHEM AL BO 0347 Protocatechuic acid 3,4-dihydroxybenzoate Carbohydroquinonic acid 3,4-DIHYDROBENZOIC ACID 3,4-Dihydroxybenzoic acid 3,4-Dihydroxy benzoic acid CATECHOL-4-CARBOXYLIC ACID PROTOCATECHUIC ACID N-HYDRATE 3,4-Dihydroxybenzoic acid N-HYDRATE cyclohexa-1,5-diene-1-carboxylic acid Protocatechuic acid, 4-Carboxybenzene-1,2-diol, 4-Carboxycatechol |
CAS | 99-50-3 |
EINECS | 202-760-0 |
InChI | InChI=1/C7H6O4/c8-5-2-1-4(7(10)11)3-6(5)9/h1-3,8-9H,(H,10,11)/p-1 |
InChIKey | YQUVCSBJEUQKSH-UHFFFAOYSA-N |
Molecular Formula | C7H6O4 |
Molar Mass | 154.12 |
Density | 1.54 |
Melting Point | 197-200 °C (dec.) (lit.) |
Boling Point | 237.46°C (rough estimate) |
Flash Point | 216.3°C |
Water Solubility | Soluble in hot alcohol and ether. Slightly soluble in water. |
Solubility | Soluble in water, ethanol, ether, acetone, slightly soluble in benzene and chloroform, insoluble in petroleum ether. |
Vapor Presure | 1.75E-07mmHg at 25°C |
Appearance | White to brown crystalline powder, discolored in air |
Color | Beige to brown |
Merck | 14,7894 |
BRN | 1448841 |
pKa | 4.48(at 25℃) |
PH | 3.78(1 mM solution);3.25(10 mM solution);2.74(100 mM solution) |
Storage Condition | Store below +30°C. |
Stability | Stable. Incompatible with strong oxidizing agents, strong bases. |
Sensitive | Air Sensitive |
Refractive Index | 1.6400 (estimate) |
MDL | MFCD00002509 |
Physical and Chemical Properties | Melting Point: 198-202°C |
Use | Used as a dye, pharmaceutical intermediates |
Hazard Symbols | Xi - Irritant |
Risk Codes | 36/37/38 - Irritating to eyes, respiratory system and skin. |
Safety Description | S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S36 - Wear suitable protective clothing. S37/39 - Wear suitable gloves and eye/face protection |
WGK Germany | 3 |
RTECS | UL0560000 |
HS Code | 29182990 |
light yellow to light brown amorphous powder. Stable to heat. d, l two isomers, mixed melting point 132. Soluble in water, ethanol, propylene glycol, glycerol and other strong polar organic solvents, insoluble in oil. It is easily oxidized in alkaline medium. The l-form has a melting point of 175 to 177 ° C. And a specific optical rotation [Alto is -16.8.
The stems and leaves of camellia, the leaves of Camellia sinensis and catechu were distilled, extracted with water or ethanol, and then refined.
can be used as an antioxidant. With vitamin E, sorbic acid, L-ascorbic acid has a synergistic antioxidant effect. It should be used in combination.
FEMA | 4430 | 3,4-DIHYDROXYBENZOIC ACID |
EPA chemical substance information | information provided by: ofmpeb.epa.gov (external link) |
Introduction | protocatechuic acid (PCA) is 3, 4-dihydroxybenzoic acid. Is a simple phenolic acid, which is a precursor for the synthesis of other complex molecules, such as anthocyanins 3-o-β-d-glucoside and vanillin. It is found in edible vegetables, fruits, nuts, brown rice, pecans, tea, hibiscus, and some herbal medicines. |
Application | protocatechuic acid has a variety of biological activities for different molecular targets, which has antibacterial, antioxidant, anti-inflammatory, antihyperglycaemic and neuroprotective effects, in addition to protocatechuic acid has a potential chemical protective effect, it can inhibit chemical carcinogens in vitro and in different aspects of pro-apoptotic and anti-proliferative effects. So at present in the clinical for Burns, children Pneumonia, bacillary dysentery, acute pyelonephritis, acute pancreatitis and some ulcer disease treatment. |
pharmacological action | protocatechuic acid is a metabolic product of complex polyphenols, such as anthocyanins and proanthocyanidins, they are high in plants and fruits and can be absorbed by animals and humans. It is estimated that the daily intake of anthocyanins is higher than other polyphenols, so the nutritional value of protocatechuic acid is more and more recognized. A large number of experiments have proved that protocatechuic acid has a variety of biological activities against different molecular targets, which has antibacterial, antioxidant, anti-inflammatory, anti-hyperglycemia and neuroprotective effects, in addition, protocatechuic acid has a potential chemical protective effect, which can inhibit chemical carcinogens in vitro and produce apoptosis-promoting and anti-proliferative effects in different aspects. |
efficacy and function | protocatechuic acid has a variety of biological activities for different molecular targets, which has antibacterial, antioxidant, anti-inflammatory, anti-hyperglycemic and neuroprotective effects, it is capable of inhibiting chemical carcinogens in vitro and producing pro-apoptotic and anti-proliferative effects in different ways. |
preparation method | using piperonal aldehyde as raw material, using potassium permanganate oxidation to prepare pepper acid, and then by aluminum trichloride hydrolysis to prepare protocatechuic acid, the synthetic route is as follows: FIG. 1 is the synthetic route 1 of protocatechuic acid. Preparation of pepper acid 12 g of piperonal and 300 ml of water were added to a 1000 ml three-necked flask, heated to 70~80 °c, with vigorous stirring, 5% potassium permanganate aqueous solution (18g of potassium permanganate plus 360 ml of water) was added dropwise for about 30 min. After the addition, stirring was continued until the purple color fades, filtration was performed while hot, and the filter cake was washed. The mother liquor was acidified and filtered to obtain pepper acid. The product was naturally dried 12.4g, with a yield of 94% and a melting point of 228~231 ℃. 2. Preparation of protocatechuic acid 4 g of aluminum trichloride was added to 150 of nitrobenzene, stirred and dissolved, 10 g of pepper acid was added in batches, stirred for 3-5 h at room temperature, the reaction solution was poured into 100 ml of water, the aqueous layer was separated, sulfur dioxide was introduced into the aqueous solution, and protocatechuic acid was precipitated. Dry weight 7.5g, melting point 200~201 deg C, the yield of 81%. |
extraction method | extraction of protocatechuic acid from clove leaves:(1) sample pretreatment. The original medicinal materials of clove leaves were dried and the seeds and various impurities were removed by selection, and crushed by a pulverizer to obtain a fine powder. (2) extraction of protocatechuic acid. 2.0g of clove leaf powder with 40 mesh sieve was weighed and extracted with anhydrous ethanol under the set process conditions. The extract was filtered, the dregs were discarded, and the ethanol was recovered to obtain the crude extract. Add 50ml ether and 3ml 0.1mol/L hydrochloric acid to the crude extract, shake it to dissolve it, transfer it to a separatory funnel, and extract it three times with 0.1mol/L sodium hydroxide solution, 50ml each time, after each extraction, the sodium hydroxide solution was washed with 10ml of ether, then 3ml of 1mol/L hydrochloric acid was added, the sodium hydroxide solution was combined, and then extracted with 50ml of ether for 3 times, the ether layers extracted three times were washed with 10ml of water, combined with ether solution, adjusted to pH 6.0, and evaporated to dryness to give almost white powdery crystals. |
Use | protocatechuic acid can be used as a dye, a pharmaceutical intermediate. It is used as an intermediate for dyes, pharmaceuticals, and Analytical reagents (assay iron). protocatechuic acid can be used to study the effects of 4-coumaric acid and 3, 4-dihydroxybenzoic acid on oxidative DNA damage in rat colonic mucosa in vivo. It can be used for derivatization of chitosan resin. |
production method | protocatechuic acid can be obtained from vanillin by alkali fusion and acidification. |