SALICYLIC ACID
SALICYLIC ACID
Salicylic acid is a beta hydroxy acid (BHA) with the formula C7H6O3, known for its bacteriostatic, fungicidal, and keratolytic actions, making it a common ingredient in topical treatments for acne, psoriasis, and warts.
Salicylic acid is also a precursor to acetylsalicylic acid (aspirin), achieved by acetylating its phenolic hydroxyl group, and is widely used in the pharmaceutical industry for its analgesic and anti-inflammatory properties.
In plants, salicylic acid acts as a signaling molecule involved in defense mechanisms, enhancing resistance to pathogens and playing a role in systemic acquired resistance.
CAS Number: 69-72-7
EC Number: 200-712-3
Molecular Formula: C7H6O3
Molecular Weight: 138.12 g/mol
Synonyms: 2-Hydroxybenzoic acid, 2-HYDROXYBENZOIC ACID, ACIDUM SALICYLICUM, ACETYLSALISYLIC ACID IMP C, ACETYLSALICYLIC ACID IMPURITY C, FEMA 3985, SALICYCLIC ACID, SALICYLIC ACID, RETARDER TSA, salicylic acid, 2-Hydroxybenzoic acid, 69-72-7, o-hydroxybenzoic acid, 2-Carboxyphenol, o-Carboxyphenol, Rutranex, Salonil, Retarder W, Duoplant, Keralyt, Psoriacid-S-stift, Freezone, Saligel, Ionil, Salicylic acid soap, Stri-Dex, Verrugon, Salicylic acid collodion,
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Salicylic acid is an organic compound with the formula HOC6H4COOH.
Salicylic acid has bacteriostatic, fungicidal, and keratolytic actions.
Salicylic acid is odourless and is colourless.
Salicylic acid is a compound obtained from the bark of the white willow and wintergreen leaves, and also prepared synthetically.
Salicylic acid has bacteriostatic, fungicidal, and keratolytic actions.
Salicylic acid is a metabolite found in or produced by Escherichia coli
Salicylic acid is a beta hydroxy acid that occurs as a natural compound in plants.
Salicylic acid has direct activity as an anti-inflammatory agent and acts as a topical antibacterial agent due to its ability to promote exfoliation.
Salicylic acid is a compound obtained from the bark of the white willow and wintergreen leaves.
Salicylic acid has bacteriostatic, fungicidal, and keratolytic actions.
A colorless, bitter-tasting solid, Salicylic acid is a precursor to and a metabolite of aspirin (acetylsalicylic acid).
Salicylic acid is a plant hormone, and has been listed by the EPA Toxic Substances Control Act (TSCA) Chemical Substance Inventory as an experimental teratogen.
The name is from Latin salix for willow tree, from which Salicylic acid was initially identified and derived.
Salicylic acid is an ingredient in some anti-acne products.
Salts and esters of Salicylic acid are known as salicylates.
Salicylic acid is an odorless white to light tan solid.
Salicylic acid sinks and mixes slowly with water.
Salicylic acid is a useful phosphor in the vacuum ultraviolet spectral range, with nearly flat quantum efficiency for wavelengths between 10 and 100 nm.
Salicylic acid fluoresces in the blue at 420 nm.
Salicylic acid is easily prepared on a clean surface by spraying a saturated solution of the salt in methanol followed by evaporation.
Salicylic acid a monohydroxybenzoic acid that is benzoic acid with a hydroxy group at the ortho position.
Salicylic acid is obtained from the bark of the white willow and wintergreen leaves.
Salicylic acid has a role as an antiinfective agent, an antifungal agent, a keratolytic drug, an EC 1.11.1.11 (L-ascorbate peroxidase) inhibitor, a plant metabolite, an algal metabolite and a plant hormone.
Salicylic acid is a conjugate acid of a salicylate.
Salicylic acid is lipophilic monohydroxybenzoic acid.
Salicylic acid a type of phenolic acid and a beta-hydroxy acid (BHA).
Beta hydroxy acid is found as a natural compound in plants.
This colourless crystalline organic acid, Salicylic acid, is broadly in use in organic synthesis.
Salicylic acid is derived from the metabolism of salicin.
Salicylic acid is a crystalline organic carboxylic acid and has keratolytic, bacteriostatic and fungicidal properties.
Salicylic acid can be in use as an antiseptic and as a food preservative when consumed in small quantities.
Salicylic acid has a carboxyl group attached to it i.e., COOH.
Salicylic acid is odourless and is colourless.
Salicylic acid is probably known for its use as an important ingredient in topical anti-acne products.
The salts and esters of Salicylic acid are salicylates.
Salicylic acid is on the World Health Organization’s List of Essential Medicines.
Salicylic acid is the safest and most effective medicines needed in a health system.
Salicylic acid, also known as 2-Hydroxybenzoic Acid, 2-Carboxyphenol, and o-Hydroxybenzoic Acid has the chemical formula C7H6O3.
Salicylic acid appears as an odorless, white-colored to light tan solid with an acrid taste.
Salicylic acid is slightly soluble in Water, therefore, when added to Water, Salicylic acid sinks and slowly mixes with it at ambient conditions.
Salicylic acid is in use in the treatment of wart infections.
The mechanism of Salicylic acid by which professionals treats warts infection is similar to its keratolytic action.
Firstly, Salicylic acid dehydrates the skin cells that are affected by warts and thereby it gradually leads to its shedding off from the body.
Salicylic acid also activates the immune reaction of the body towards the viral wart infection by initiating a mild inflammatory reaction.
Salicylic acid is one of the major components of anti-dandruff shampoos.
Salicylic acid also helps in clearing away the dead and flaky skin cells from your scalp.
Salicylic acid is a monohydroxybenzoic acid, benzoic acid with a hydroxy group in the ortho position.
Salicylic acid is obtained from the bark of white willow and wintergreen leaves.
Salicylic acid has a role as antiinfective agent, antifungal agent, keratolytic drug, EC 1.11.1.11 (L-ascorbate peroxidase) inhibitor, plant metabolite, algal metabolite and plant hormone.
Salicylic acid is the conjugate acid of a salicylate.
Salicylic acid, also known as o-hydroxybenzoic acid, is a component with a structure similar to β-hydroxy acid, which can not only soften the stratum corneum, but also loosen the horn plugs to unclog pores, as well as certain antibacterial and anti-inflammatory effects.
Salicylic acid is not easily soluble in water, but is easily soluble in organic solvents such as ethanol, ether, propanol, and turpentine.
Salicylic acid exists in willow bark, white pearl leaves, and sweet birch in nature, and is the “anti-inflammatory drug” of plants.
Humans have long discovered the medicinal properties of willow plant extracts (natural Salicylic acid).
Ancient Sumerian clay tablets have records of using willow leaves to treat arthritis.
The oldest medical text in ancient Egypt, the Ebers Papyrus, records that the pain-relieving properties of dried willow leaves were known to the Egyptians at least more than 2,000 BC.
The ancient Greek physician Hippocrates documented the medicinal properties of willow bark in the 5th century BC.
This knowledge was repeatedly quoted by famous Greek and Roman physicians such as Galen.
These are ortho-hydroxylated benzoic acids.
Salicylic acid exists in all living species, ranging from bacteria to plants to humans.
Based on a literature review a significant number of articles have been published on Salicylic acid.
Salicylic acid, also called 2-hydrobenzoic or phenolic acid, is a colorless substance in the form of crystals or powder.
Salicylic acid is one of the most commonly used types of hydroxybenzoic acid.
Phenolic acid is highly soluble in polar solvents of organic origin, such as diethyl ether or ethanol, but slightly soluble in water and carbon disulfide.
The density of Salicylic acid is 1.44 g/cm³, melting occurs at 159°C, and boils at 211°C.
The production of Salicylic acid is based on the Kolbe-Schmitt reaction: the carboxylation of sodium phenolate when exposed to carbon dioxide with the creation of the required pressure and temperature for 8-10 hours.
Two grades of the product are produced: A – for the preparation of medicines, B – for other areas of application.
The chemical formula of Salicylic acid is C7H6O3.
Salicylic acid is a natural product extract from Willow bark, well known as an antiinflammatory and antinociceptive agent and a close structural relative to acetylsalicylic acid (aspirin).
Salicylic acid is a ubiquitous plant hormone with many regulatory functions involved in local disease resistance mechanisms and systemic acquired resistance.
The antiinflammatory and antinociceptive effects produced by Salicylic acid and its derivatives in animals are due to inhibition of COX-1 and COX-2 (cyclooxygenase) enzyme activity and suppression of prostaglandin biosynthesis.
Salicylic acid is also of interest as a starting material for the organic synthesis of more elaborate COX suppressors and other chemical structures.
Salicylic acid (from Latin salix, willow tree) is a monohydroxybenzoic acid, a type of phenolic acid and a beta hydroxy acid.
Salicylic acid has the formula C7H6O3.
In an early (1966) biosynthetic process, researchers at Kerr-McGee Oil Industries (now part of Andarko Petroleum) prepared Salicylic acid via the microbial degradation of naphthalene.
Salicylic acid is now commercially biosynthesized from phenylalanine.
Acetylsalicylic acid (aspirin), a prodrug to Salicylic acid, is made by an entirely different process.
Curiously, Salicylic acid is also a metabolite of aspirin.
Salicylic acid and its esters are used as food preservatives, in skin-care products and other cosmetics, and in topical medicines.
Salicylic Acid in Signal Transduction:
A number of proteins have been identified that interact with Salicylic acid in plants, especially Salicylic acid binding proteins (SABPs) and the NPR genes (nonexpressor of pathogenesis-related genes), which are putative receptors.
Salicylic acid is an effective inhibitor of COX-2 activity at concentrations far below those required to inhibit NF-κB (20 mg/mL) activation.
Salicylic acid inhibits prostaglandin E2 release when add together with interleukin 1β for 24 hr with an IC50 value of 5 μg/mL, an effect that is independent of NF-κB activation or COX-2 transcription or translation.
Salicylic acid acutely (30 min) also causes a concentration-dependent inhibition of COX-2 activity measured in the presence of 0, 1, or 10 μM exogenous arachidonic acid.
In contrast, when exogenous arachidonic acid is increased to 30 μM, Salicylic acid is a very weak inhibitor of COX-2 activity with an IC50 of >100 μg/mL.
When added together with IL-1β for 24 hr, Salicylic acid causes a concentration-dependent inhibition of PGE2 release with an apparent IC50 value of approximately 5 μg/mL.
The ability of Salicylic acid to directly inhibit COX-2 activity in A549 cells is tested after a 30-min exposure period, followed by the addition of different concentrations of exogenous arachidonic acid (1, 10, and 30 μM).
Salicylic acid causes a concentration-dependent inhibition of COX-2 activity in the absence of added arachidonic acid or in the presence of 1 or 10 μM exogenous substrate with an apparent IC50 value of approximately 5 μg/mL.
However, when the same experiments are performed using 30 μM arachidonic acid, Salicylic acid is an ineffective inhibitor of COX-2 activity, with an apparent IC50 value of more than 100 μg/mL, and achieves a maximal inhibition of less than 50%.
Salicylic Acid in Plant Hormone:
Salicylic acid is a phenolic phytohormone, and is found in plants with roles in plant growth and development, photosynthesis, transpiration, and ion uptake and transport.
Salicylic acid is involved in endogenous signaling, mediating plant defense against pathogens.
Salicylic acid plays a role in the resistance to pathogens (i.e. systemic acquired resistance) by inducing the production of pathogenesis-related proteins and other defensive metabolites.
Salicylic acid’s defense signaling role is most clearly demonstrated by experiments which do away with it: Delaney et al. 1994, Gaffney et al. 1993, Lawton et al. 1995, and Vernooij et al. 1994 each use Nicotiana tabacum or Arabidopsis expressing nahG, for salicylate hydroxylase.
Pathogen inoculation did not produce the customarily high Salicylic acid levels, SAR was not produced, and no PR genes were expressed in systemic leaves. Indeed, the subjects were more susceptible to virulent – and even normally avirulent – pathogens.
Exogenously, Salicylic acid can aid plant development via enhanced seed germination, bud flowering, and fruit ripening, though too high of a concentration of Salicylic acid can negatively regulate these developmental processes.
The volatile methyl ester of Salicylic acid, methyl salicylate, can also diffuse through the air, facilitating plant-plant communication.
Methyl salicylate is taken up by the stomata of the nearby plant, where it can induce an immune response after being converted back to Salicylic acid.
Uses of Salicylic Acid:
Salicylic acid is used as a food preservative, a bactericide, and an antiseptic.
Salicylic acid is used in the production of other pharmaceuticals, including 4-aminosalicylic acid, sandulpiride, and landetimide (via salethamide).
Salicylic acid has long been a key starting material for making acetylsalicylic acid (aspirin).
Aspirin (acetylsalicylic acid or ASA) is prepared by the esterification of the phenolic hydroxyl group of Salicylic acid with the acetyl group from acetic anhydride or acetyl chloride.
Acetylsalicylic acid is the standard to which all the other non-steroidal anti-inflammatory drugs (NSAIDs) are compared.
In veterinary medicine, this group of drugs is mainly used for treatment of inflammatory musculoskeletal disorders.
Bismuth subsalicylate, a salt of bismuth and Salicylic acid, “displays anti-inflammatory action (due to salicylic acid) and also acts as an antacid and mild antibiotic”.
Salicylic acid is the active ingredient in stomach-relief aids such as Pepto-Bismol and some formulations of Kaopectate.
Other derivatives include methyl salicylate used as a liniment to soothe joint and muscle pain and choline salicylate used topically to relieve the pain of mouth ulcers.
Aminosalicylic acid is used to induce remission in ulcerative colitis, and has been used as an antitubercular agent often administered in association with isoniazid.
Salicylic acid’s salts, the salicylates, are used as analgesics.
Salicylic acid is used in the following products: Fertilizers, cosmetics and personal care products, laboratory chemicals and medicines.
Salicylic acid is used in agriculture, forestry and fisheries, health care and scientific research and development
Salicylic acid is used in machine wash fluids/detergents, automotive care products, paints, coatings or adhesives, fragrances, air fresheners, coolants in refrigerators and oil-based electric heaters.
Salicylic acid is particularly in use in the pharmaceutical industry.
The most common use of Salicylic acid is in the preparation of an analgesic, aspirin, which is an acetylated derivative of Salicylic acid.
Another analgesic formed from it is methyl salicylate, an esterified product of Salicylic acid.
Both of these analgesics are in use to treat headache and other body aches.
Salicylic acid also in use as a mild antiseptic effect known as a bacteriostatic agent.
Salicylic acid does not kill the existing bacteria and hence not an antibacterial agent but prevent the growth of bacteria wherever applied.
Common Uses and Applications of Salicylic acid: Treatment for various minor skin conditions, Food preservative, Analytic reagent, Industries,Food & Beverage, Pharmaceutical, and R&D/Laboratory.
Salicylic acid is a white solid first isolated from the bark of willow trees (Salix spp.), from which it gets its name.
Salicylic acid is used semiconductors, nanoparticles, photoresists, lubricating oils, UV absorbers, adhesive, leather, cleaner, hair dye, soaps, cosmetics, pain medication, analgesics, antibacterial agent, treatment of dandruff, hyperpigmented skin, tinea pedis, onychomycosis, osteoporosis, beriberi, fungicidal skin disease, autoimmune disease.
In medicine, preparations based on Salicylic acid are used as an antipyretic, antiseptic, antirheumatic and anti-tuberculosis agent, which has an analgesic and anti-inflammatory effect.
These are aspirin, salicylamide, para-aminosalicylic acid, Lassar paste, preparations for the treatment of corns, ointments, powders.
At food enterprises, Salicylic acid is used as an antiseptic in the manufacture of canned foods.
Salicylic acid is added as a component to cosmetics.
Salicylic acid’s antibacterial and exfoliating properties make Salicylic acid possible to soften and remove the keratinized top layer of the skin.
Salicylic acid is used as a reagent and indicator in chemical reactions.
Salicylic acid is used ass a reference standard in salicylate quantification by reverse-phase high-performance liquid chromatography (RP-HPLC).
Both oil of wintergreen (methyl 2-hydroxybenzoate) and Salicylic acid (2-hydroxybenzoic acid) are widely used as pharmaceuticals.
The manufacture of aspirin from Salicylic acid is of major importance.
Industrially, Salicylic acid is manufactured at high temperature and pressure from the phenol sodium salt and carbon dioxide, with an annual worldwide production of about 50,000 tonnes.
Salicylic acid also occurs as the free acid or its esters in many plant species.
Salicylic acid can be made from methyl 2-hydroxybenzoate which is obtained as oil of wintergreen by distillation from the leaves of Gaultheria procunbers.
Medicine uses:
Salicylic acid as a medication is commonly used to remove the outer layer of the skin.
As such, Salicylic acid is used to treat warts, psoriasis, acne vulgaris, ringworm, dandruff, and ichthyosis.
Similar to other hydroxy acids, Salicylic acid is an ingredient in many skincare products for the treatment of seborrhoeic dermatitis, acne, psoriasis, calluses, corns, keratosis pilaris, acanthosis nigricans, ichthyosis, and warts.
Functions of Salicylic Acid:
Acne treatment, acne treatment:
Salicylic acid is fat-soluble, can penetrate deep into pores to dissolve oil and unclog sebaceous glands.
Salicylic acid’s acidity can dissolve hardened oil and keratin, so that the keratin plugs in the hair follicles can be loosened, and Salicylic acid also has mild anti-inflammatory properties.
Conditioning keratin and improving skin photoaging
Salicylic acid has a two-way keratin regulating effect and can remove old keratin, so some patients will experience slight scaling, but this is a manifestation of keratin renewal, and Salicylic acid is not suitable for immature keratinization.
On the contrary, the stratum corneum cells have the effect of promoting keratinization and maturation.
Long-term sunlight exposure can cause skin keratin thickening, skin hypertrophy, skin furrows deepen, skin ridges bulge, forming thick and deep wrinkles, so Salicylic acid can improve skin aging caused by sun exposure.
Anti-inflammatory and bactericidal:
Topical application of Salicylic acid has different degrees of anti-inflammatory, astringent and antipruritic effects on seborrheic dermatitis, papulopustular rosacea, and folliculitis.
The anti-inflammatory effect of aspirin comes from the Salicylic acid formed after being decomposed in the body; and Salicylic acid has a certain broad-spectrum bactericidal ability and is effective against many bacteria and fungi.
Whitening, Eliminate Pigmentation:
Salicylic acid penetrates into pores, dissolves aging keratinocytes, lightens pigmentation and enhances skin cell metabolism.
Salicylic acid can dissolve the connection between the skin cutin, make the cuticle fall off, remove the excessively thick cuticle, promote epidermal metabolism, rejuvenate and whiten the skin, prevent the generation of acne marks, remove the acne marks that have already occurred, and can prevent UV damage and photoaging.
Dietary Sources of Salicylic Acid:
Salicylic acid occurs in plants as free Salicylic acid and its carboxylated esters and phenolic glycosides.
Several studies suggest that humans metabolize Salicylic acid in measurable quantities from these plants.
High-salicylate beverages and foods include beer, coffee, tea, numerous fruits and vegetables, sweet potato, nuts, and olive oil.
Meat, poultry, fish, eggs, dairy products, sugar, breads and cereals have low salicylate content.
Some people with sensitivity to dietary salicylates may have symptoms of allergic reaction, such as bronchial asthma, rhinitis, gastrointestinal disorders, or diarrhea, so may need to adopt a low-salicylate diet.
Experimental Properties of Salicylic Acid:
Physical Properties:
Salicylic acid is a colourless, odourless and needle-shaped crystals at room temperature.
The taste of Salicylic acid is acrid.
The boiling point and melting point of Salicylic acid are 211oC and 315oC respectively.
The Salicylic acid molecule has two hydrogen bond donors and three hydrogen bond acceptors.
The flashpoint of Salicylic acid is 157oC.
Due to Salicylic acid’s lipophilic nature, its solubility in water is very poor i.e., 1.8 g/L at 25oC.
Salicylic acid is soluble in organic solvents like carbon tetrachloride, benzene, propanol, ethanol and acetone.
The density ofSalicylic acid is 1.44 at 20oC.
Salicylic acid’s vapour pressure is 8.2×105mmHg at 25oC.
Salicylic acid is a tendency to undergo discolouration when exposed to direct sunlight due to its photochemical degradation.
Salicylic acid’s heat of combustion is 3.026mj/mole at 25oC.
The pH of a saturated solution of Salicylic acid is 2.4.
Salicylic acid’s pka value i.e., dissociation constant is 2.97.
Chemical Properties:
Formation of aspirin:
In the pharmaceutical industry, the most important reaction associated with the use of Salicylic acid is the production of aspirin i.e., acetylsalicylic acid.
Salicylic acid is one of the most commonly used analgesics and blood-thinning agent.
In this reaction, Salicylic acid is reacting with acetic anhydride.
Salicylic acid leads to the acetylation of the hydroxyl group present in the Salicylic acid, thereby resulting in the production of acetylsalicylic acid i.e., aspirin.
Acetic acid is manufactured as a byproduct of this reaction.
This is also present as one of the impurities during large scale production of aspirin.
These impurities must be removed from the resulting product mixture by several refining processes.
Esterification Reaction:
Since Salicylic acid is an organic acid, it undergoes a reaction with organic alcohol groups to produce a new organic chemical class alike ester.
When Salicylic acid is reacting with methanol in an acidic medium preferably sulphuric acid in the presence of heat, a dehydration reaction occurs with the loss of water −OH− ion.
This ion is lost from the carboxylic acid functional group present in the Salicylic acid molecule and the H+ ion is lost from the deprotonation of the methanol molecule, resulting in the formation of methyl salicylate (an ester).
Preparation Methods of Salicylic Acid:
There are two most common methods in use for the preparation of Salicylic acid are as follows:
From Phenol:
When phenol is reacted with sodium hydroxide, Salicylic acid forms sodium phenoxide.
Sodium phenoxide then undergoes distillation and dehydration.
This process is followed by a carboxylation reaction with carbon dioxide, which results in the formation of sodium salicylate i.e., salt of Salicylic acid.
This salt then further reacted with an acid or hydronium ion or any species that denotes a proton to obtain the Salicylic acid.
From Methyl Salicylate:
Methyl salicylate also known as oil of wintergreen is commonly called analgesic in the pharmaceutical industry.
Salicylic acid is in use for the preparation of Salicylic acid.
In this reaction, methyl salicylate is reacted with sodium hydroxide (NaOH) to lead to the formation of a sodium salt intermediate of Salicylic acid.
Salicylic acid is named disodium salicylate, which upon undergoing further reaction with sulphuric acid leads to the formation of Salicylic acid.
Structure of Salicylic Acid:
The structural formula of Salicylic acid is C6H4(OH)COOH.
The chemical formula of Salicylic acid can also be written as C7H6O3 in the condensed form.
The IUPAC name of Salicylic acid is 2-hydroxybenzoic acid.
Salicylic acid has a hydroxyl group i.e., -OH group attached at the ortho position with respect to the carboxylic acid.
This COOH group is present on the benzene ring.
The molecular weight or molar mass of Salicylic acid is 138.12 g/mol.
All carbon atoms present in the benzene ring of Salicylic acid are sp2 hybridized.
Salicylic acid forms an intramolecular hydrogen bond.
In an aqueous solution, Salicylic acid dissociates to lose a proton from the carboxylic acid.
The resulting carboxylate ion i.e., −COO− undergoes intermolecular interaction with the hydrogen atom of the hydroxyl group i.e., -OH.
Salicylic acid leads to the formation of an intramolecular hydrogen bond.
Chemical Synthesis of Salicylic Acid:
Commercial vendors prepare sodium salicylate by treating sodium phenolate (the sodium salt of phenol) with carbon dioxide at high pressure (100 atm) and high temperature (115 °C) – a method known as the Kolbe-Schmitt reaction.
Acidifying the product with sulfuric acid gives Salicylic acid:
At the laboratory scale, Salicylic acid can also be prepared by the hydrolysis of aspirin (acetylsalicylic acid) or methyl salicylate (oil of wintergreen) with a strong acid or base; these reactions reverse those chemicals’ commercial syntheses.
Production and Chemical Reactions of Salicylic Acid:
Biosynthesis:
Salicylic acid is biosynthesized from the amino acid phenylalanine.
In Arabidopsis thaliana, Salicylic acid can be synthesized via a phenylalanine-independent pathway.
Reactions:
Upon heating, Salicylic acid converts to phenyl salicylate:
2 HOC6H4CO2H → C6H5O2C6H4OH + CO2 + H2O
Further heating gives xanthone.
Salicylic acid as its conjugate base is a chelating agent, with an affinity for iron(III).
Salicylic acid slowly degrades to phenol and carbon dioxide at 200–230 °C:
C6H4OH(CO2H) → C6H5OH + CO2
Action Mechanism of Salicylic Acid:
Salicylic acid modulates COX-1 enzymatic activity to decrease the formation of pro-inflammatory prostaglandins.
Salicylate may competitively inhibit prostaglandin formation.
Salicylate’s antirheumatic (nonsteroidal anti-inflammatory) actions are a result of its analgesic and anti-inflammatory mechanisms.
Salicylic acid, when applied to the skin surface, works by causing the cells of the epidermis to slough off more readily, preventing pores from clogging up, and allowing room for new cell growth.
Salicylic acid inhibits the oxidation of uridine-5-diphosphoglucose (UDPG) competitively with NADH and noncompetitively with UDPG.
Salicylic acid also competitively inhibits the transferring of glucuronyl group of uridine-5-phosphoglucuronic acid to the phenolic acceptor.
The wound-healing retardation action of salicylates is probably due mainly to Salicylic acid’s inhibitory action on mucopolysaccharide synthesis.
History of Salicylic Acid:
Willow has long been used for medicinal purposes.
Dioscorides, whose writings were highly influential for more than 1,500 years, used ‘Itea’ (which was possibly a species of willow) as a treatment for ‘painful intestinal obstructions,’ birth control, for ‘those who spit blood,’ to remove calluses and corns and, externally, as a ‘warm pack for gout.’
William Turner, in 1597, repeated this, saying that willow bark, ‘being burnt to ashes, and steeped in vinegar, takes away corns and other like risings in the feet and toes.’
Some of these cures may describe the action of Salicylic acid, which can be derived from the salicin present in willow.
Salicylic acid was used in Europe and China to treat these conditions.
This remedy is mentioned in texts from Ancient Egypt, Sumer, and Assyria.
The Cherokee and other Native Americans use an infusion of the bark for fever and other medicinal purposes.
In 2014, archaeologists identified traces of Salicylic acid on seventh-century pottery fragments found in east-central Colorado.
The Reverend Edward Stone, a vicar from Chipping Norton, Oxfordshire, England, reported in 1763 that the bark of the willow was effective in reducing a fever.
An extract of willow bark, called salicin, after the Latin name for the white willow (Salix alba), was isolated and named by German chemist Johann Andreas Buchner in 1828.
A larger amount of the substance was isolated in 1829 by Henri Leroux, a French pharmacist.
Raffaele Piria, an Italian chemist, was able to convert the substance into a sugar and a second component, which on oxidation becomes Salicylic acid.
Salicylic acid was also isolated from the herb meadowsweet (Filipendula ulmaria, formerly classified as Spiraea ulmaria) by German researchers in 1839.
Salicylic acid’s extract causes digestive problems such as gastric irritation, bleeding, diarrhea, and even death when consumed in high doses.
In 1874 the Scottish physician Thomas MacLagan experimented with salicin as a treatment for acute rheumatism, with considerable success, as he reported in The Lancet in 1876.
Meanwhile, German scientists tried sodium salicylate with less success and more severe side effects.
In 1979, salicylates were found to be involved in induced defenses of tobacco against tobacco mosaic virus.
In 1987, Salicylic acid was identified as the long-sought signal that causes thermogenic plants, such as the voodoo lily, Sauromatum guttatum, to produce heat.
Handling and Storage of Salicylic Acid:
Conditions for safe storage, including any incompatibilities:
Storage conditions:
Tightly closed.
Dry.
Store at Room Temperature.
Light sensitive
Stability and Reactivity of Salicylic Acid:
Chemical stability:
The product is chemically stable under standard ambient conditions (room temperature).
Incompatible materials:
No data available
First Aid Measures of Salicylic Acid:
General advice:
Show this material safety data sheet to the doctor in attendance.
If inhaled:
After inhalation:
Fresh air.
Call in physician.
In case of skin contact:
Take off immediately all contaminated clothing.
Rinse skin with water/ shower.
Consult a physician.
In case of eye contact:
After eye contact:
Rinse out with plenty of water.
Immediately call in ophthalmologist.
Remove contact lenses.
If swallowed:
After swallowing:
Immediately make victim drink water (two glasses at most).
Consult a physician.
Indication of any immediate medical attention and special treatment needed:
No data available
Fire Fighting Measures of Salicylic Acid:
Suitable extinguishing media:
Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.
Further information:
Prevent fire extinguishing water from contaminating surface water or the ground water system.
Accidental Release Measures of Salicylic Acid:
Environmental precautions:
Do not let product enter drains.
Methods and materials for containment and cleaning up:
Cover drains.
Collect, bind, and pump off spills.
Observe possible material restrictions.
Take up dry.
Dispose of properly.
Clean up affected area.
Exposure Controls/Personal Protection of Salicylic Acid:
Personal protective equipment:
Eye/face protection:
Use equipment for eye protection.
Tightly fitting safety goggles
Skin protection:
Full contact:
Material: Nitrile rubber
Minimum layer thickness: 0,11 mm
Break through time: 480 min
Splash contact:
Material: Nitrile rubber
Minimum layer thickness: 0,11 mm
Break through time: 480 min
Body Protection:
Protective clothing
Control of environmental exposure:
Do not let product enter drains.
Identifiers of Salicylic Acid:
Formula: C7H6O3
Molecular weight: 138,12 g/mol
CAS-No.: 69-72-7
EC-No.: 200-712-3
CAS number: 69-72-7
EC number: 200-712-3
Hill Formula: C₇H₆O₃
Chemical formula: HOC₆H₄COOH
Molar Mass: 138.12 g/mol
HS Code: 2918 21 10
Boiling point: 211 °C (1013 hPa)
Density: 1.44 g/cm3 (20 °C)
Flash point: 157 °C
Ignition temperature: 500 °C
Melting Point: 158 – 160 °C
pH value: 2.4 (H₂O, 20 °C) (saturated solution)
Vapor pressure: 1 hPa (114 °C)
Bulk density: 400 – 500 kg/m3
Solubility: 2 g/l
Chemical formula: C7H6O3
Molar mass: 138.122 g/mol
Appearance: Colorless to white crystals
CAS number: 69-72-7
EC number: 200-712-3
Hill Formula: C₇H₆O₃
Chemical formula: HOC₆H₄COOH
Molar Mass: 138.12 g/mol
HS Code: 2918 21 10
Boiling point: 211 °C (1013 hPa)
Density: 1.44 g/cm3 (20 °C)
Flash point: 157 °C
Ignition temperature: 500 °C
Melting Point: 158 – 160 °C
pH value: 2.4 (H₂O, 20 °C) (saturated solution)
Vapor pressure: 1 hPa (114 °C)
Bulk density: 400 – 500 kg/m3
Solubility: 2 g/l
CAS number: 69-72-7
Weight Average: 138.1207
Monoisotopic: 138.031694058
InChI Key: YGSDEFSMJLZEOE-UHFFFAOYSA-N
Properties of Salicylic Acid:
Physical state: powdercrystalline
Color: white
Odor: odorless
Melting point/freezing point:
Melting point/range: 158 – 160 °C
Initial boiling point and boiling range: 211 °C at 27 hPa
Flammability (solid, gas): No data available
Upper/lower flammability or explosive limits:
Lower explosion limit: 1,1 %(V)
Flash point 157 °C – closed cup
Autoignition temperature: No data available
Decomposition temperature: No data available
pH: 2,4 at 20 °C
Viscosity:
Viscosity, kinematic: No data available
Viscosity, dynamic: No data available
Water solubility: No data available
Partition coefficient: n-octanol/water:
log Pow: 2,25 at 25 °C – Bioaccumulation is not expected.
Vapor pressure: 1 hPa at 114 °C
Density: 1,44 g/cm3 at 20 °C
Relative density: No data available
Relative vapor density: No data available
Particle characteristics: No data available
Explosive properties: No data available
Oxidizing properties: none
Other safety information: No data available
Chemical Name : 2 – Hydroxybenzoic Acid
Molecular Formula : C7H6O3
Molecular Weight : 138.1
Description : White / colourless, crystalline powder / acicular crystals
Molecular Weight: 138.12 g/mol
XLogP3: 2.3
Hydrogen Bond Donor Count: 2
Hydrogen Bond Acceptor Count: 3
Rotatable Bond Count: 1
Exact Mass: 138.031694049 g/mol
Monoisotopic Mass: 138.031694049 g/mol
Topological Polar Surface Area: 57.5Ų
Heavy Atom Count: 10
Complexity: 133
Isotope Atom Count: 0
Defined Atom Stereocenter Count: 0
Undefined Atom Stereocenter Count: 0
Defined Bond Stereocenter Count: 0
Undefined Bond Stereocenter Count: 0
Covalently-Bonded Unit Count: 1
Compound Is Canonicalized: Yes
Odor: Odorless
Density: 1.443 g/cm3 (20 °C)
Melting point: 158.6 °C (317.5 °F; 431.8 K)
Boiling point: 211 °C (412 °F; 484 K) at 20 mmHg
Sublimation conditions: Sublimes at 76 °C
Solubility in water:
1.24 g/L (0 °C)
2.48 g/L (25 °C)
4.14 g/L (40 °C)
17.41 g/L (75 °C)
77.79 g/L (100 °C)
Solubility: Soluble in ether, CCl4, benzene, propanol,
acetone, ethanol, oil of turpentine, toluene
Solubility in benzene:
0.46 g/100 g (11.7 °C)
0.775 g/100 g (25 °C)
0.991 g/100 g (30.5 °C)
2.38 g/100 g (49.4 °C)
4.4 g/100 g (64.2 °C)
Thermochemistry of Salicylic Acid:
Std enthalpy of formation (ΔfH⦵298): −589.9 kJ/mol
Std enthalpy of combustion (ΔcH⦵298): -3.025 MJ/mol