Salicylic acid (from the Latin Salix - willow, from the bark of which it was first isolated) - 2-hydroxybenzoic acid, C 6 H 4 (OH) COOH; colorless crystals, highly soluble in ethanol, diethyl ether and other polar organic solvents, poorly soluble in water (1.8 g/l at 20 °C).
Isolated from willow bark by the Italian chemist Rafael Piria and then synthesized by him.
Occurs in nature in plants in the form of derivatives - mainly in the form of a methyl ester glycoside (in particular, salicylic acid was first isolated from the bark of willow (Salix L.), hence the name), free salicylic acid along with salicylic aldehyde in small quantities found in essential oil extracted from the flowers of some species of spirea (Spiraea ulmaria, Spiraea digitata).
Physical properties
Salicylic acid is easily soluble in ethanol and diethyl ether, and slightly soluble in carbon disulfide.
Physiological role and action of salicylates.
Effect on humans and animals:
Salicylic acid and salicylates, as well as its esters (methyl salicylate) and other synthetic derivatives of salicylic acid (for example, acetylsalicylic acid - aspirin), have a pronounced anti-inflammatory effect.
Application in medicine:
Salicylic acid is the active component of willow bark. Back in the 19th century. it was used to treat rheumatism and uric acid diathesis, and today this substance is synthesized in large quantities, as it serves as the basis for the production of many drugs.
Salicylic acid has weak antiseptic, irritant and keratolytic (in high concentrations) properties and is used externally in medicine in ointments, pastes, powders and solutions in the treatment of skin diseases; is part of Lassara paste, galmanin powder, corn liquid and corn plaster preparations.
Salicylic acid derivatives are also used in medicine (sodium salicylate), its amide (salicylamide) and acetylsalicylic acid (aspirin) are used as antipyretic, antirheumatic, anti-inflammatory and analgesic agents; phenyl salicylate - as an antiseptic, para-aminosalicylic acid (structurally similar to para-aminobenzoic acid, necessary for tuberculous mycobacteria, and therefore metabolically competing with it) - as a specific anti-tuberculosis agent.
Other Applications
Due to its antiseptic effect, salicylic acid is used in food preservation; It is also used in the production of azo dyes, aromatic substances (salicylic acid esters), for the colorimetric determination of Fe and Cu, and for separating thorium from other elements.
Salicylic acid, its acidic properties.
Salicylic (o-hydroxybenzoic) acid is a phenolic acid. As a compound with ortho functional groups, it is easily decarboxylated when heated to form phenol. Salicylic acid is soluble in water and is a stronger acid than benzoic acid (pKa = 4.17). The increased stability of the salicylate ion is explained by the formation of an intramolecular hydrogen bond.
Salicylic acid gives intense coloration with iron (III) chloride, which is due to the presence of a free phenolic hydroxyl group.
It has antirheumatic, antipyretic and antifungal effects, but since it is a strong acid, it is used only externally. Its derivatives - salts or esters - are used internally.
The following salicylic acid derivatives find practical application:
Sodium salicylate has anti-inflammatory, antipyretic and analgesic effects.
Due to its irritating and toxic effects, methyl salicylate is used only externally; included in ointments and rubs.
Phenyl salicylate is not hydrolyzed in the acidic environment of the stomach, but decomposes only in the intestine. It is used as a disinfectant for intestinal diseases, and is also used as a material for the protective coatings of certain medications that are unstable in the acidic environment of the stomach.
Acetylsalicylic acid (aspirin) has anti-inflammatory, antipyretic and analgesic effects, and is also used as an antiplatelet agent (prevents platelet aggregation and thrombus formation).
MINISTRY OF EDUCATION AND SCIENCE OF THE RF
Federal State Autonomous Educational Institution of Higher Professional Education
"Immanuel Kant Baltic Federal University"
FACULTY OF MEDICINE General Medicine
Heterofunctional benzene derivatives as
medicines
Performed:
Alexandrovich Yulia Alexandrovna
1st year student, 4A group.
Checked:
Myamina Maria Alekseevna.
Kaliningrad
Heterofunctional benzene derivatives as drugs
The inextricable connection between chemistry and medicine is clearly manifested in the field of creation and use of medicines. Back in the 16th century. The founder of iatrochemistry, Paracelsus, argued that “the real purpose of chemistry is not to make gold, but to prepare medicines.” Since ancient times, biologically active organic compounds have been selected empirically, and the emergence of a number of drugs was often due to chance. Currently, all synthesized compounds must be tested for biological activity (biological screening). This is important for identifying general patterns of relationship between the structure of compounds and their biological activity. The “structure-property” problem serves as the foundation for the targeted creation of effective medicines.
In recent decades, many new drugs have emerged. However, some groups of previously known drugs remain of great importance, in particular those with a benzene ring as a structural basis.
Benzene itself can cause acute and chronic poisoning. It has an irritating effect on the skin; its vapors in high concentrations cause agitation and respiratory distress.
Monofunctional benzene derivatives in most cases also have pronounced toxic properties. Phenol, aniline, and aromatic halogen derivatives serve as starting or intermediate products of the large-scale chemical industry. In this regard, it is necessary to take into account their toxic effect.
Benzoic acid. It is used in the form of sodium salt as an expectorant. In free form, benzoic acid is found in some resins and balms, as well as in cranberries, lingonberries, but more often
found in bound form, for example as an N-benzoyl derivative of aminoacetic acid, called hippuric acid. This acid is formed in the liver from benzoic and aminoacetic (glycine) acids and is excreted in the urine. In clinical practice, the effectiveness of the neutralizing function of the liver is judged by the amount of hippuric acid in the urine of patients (after taking sodium benzoate).
OOPantothenic acid in the human and animal body is part of coenzyme A (coenzyme A), which takes part in such biochemical processes as oxidative decarboxylation of α-keto acids (pyruvate, α-ketoglutarate), β-oxidation and biosynthesis of higher fatty acids, synthesis steroid hormones, triacylglycerols, phospholipids, acetylcholine, hippuric acid, heme hemoglobin and others, acting as an intermediate acceptor and transporter of various acidic residues (acyls) and forming so-called acyl derivatives of coenzyme A (including acetyl-CoA - the key metabolite through which there is an interaction between protein, carbohydrate and lipid metabolism).
i-Aminophenol and its derivatives. As a heterofunctional compound, p-aminophenol can form derivatives of each functional group separately and simultaneously of two functional groups. P-aminophenol itself is poisonous; Of medical interest is its derivative, paracetamol, which has an analgesic (pain-relieving) and antipyretic effect.
The drug is used for headaches, myalgia, neuralgia, arthralgia, for pain in the postoperative period, for pain caused by malignant tumors, to reduce temperature during fever. It is well tolerated. In therapeutic doses it rarely causes side effects. Skin (paracetamol is included in many combination drugs (Coldrex, Solpadeine, Panadeine, Citramon-P, etc.)) allergic reactions are possible.
Unlike acetylsalicylic acid, it does not have a damaging effect on the gastric mucosa and does not affect platelet aggregation (since it does not inhibit COX-1). The main disadvantage of paracetamol is its small therapeutic range. Toxic doses exceed the maximum therapeutic doses by only 2-3 times. In case of acute paracetamol poisoning, serious damage to the liver and kidneys is possible. They are associated with the accumulation of a toxic metabolite - N-acetyl-p-benzoquinone imine. When taking therapeutic doses, this metabolite is inactivated due to conjugation with glutathione. At toxic doses, complete inactivation of the metabolite does not occur. The remaining part of the active metabolite interacts with cells and causes their death. This leads to necrosis of liver cells and renal tubules (24-48 hours after poisoning). Treatment of acute poisoning with paracetamol includes gastric lavage, the use of activated charcoal, as well as the administration of acetylcysteine (increases the formation of glutathione in the liver) and methionine (stimulates the conjugation process). The administration of acetylcysteine and methionine is effective in the first 12 hours after poisoning, until irreversible cell changes occur.
i-Aminobenzoic acid (PABA) and its derivatives . Esters of aromatic amino acids are capable of causing local anesthesia to varying degrees. This property is especially noticeable in para-derivatives. In medicine, anesthesin (PABA ethyl ester) and novocaine (PABA 2-diethylaminoethyl ester) are used. Novocaine is used in the form of a salt (hydrochloride), which is due to the need to increase its solubility in water.
Anestezin- one of the very first synthetic compounds used as local anesthetics. Despite its existence for more than 100 years (synthesized in 1890; used since the late 90s), it is still relatively widely used alone and in combination with other drugs. Recently, a new aerosol preparation "Amprovisol" containing anesthesin has been proposed.
Anestezin is an active superficial local anesthetic. Due to its poor solubility in water, the drug is not used parenterally and for pain relief during surgical operations. However, it is widely used in the form of ointments, powders and other dosage forms for urticaria, skin diseases accompanied by itching, as well as for pain relief on wounds and ulcers. Use 5 - 10% ointments or powders and ready-made medications (Menovazin, Amprovisol, etc.).
Novocaine(procaine hydrochloride) is an ester of diethylaminoethanol and para-aminobenzoic acid. In medical practice it is used in the form of hydrochloride. It has a fairly pronounced anesthetic activity, but is inferior in this regard to other drugs. The duration of infiltration anesthesia is 30 min-1 hour. The great advantage of novocaine is its low toxicity. This also applies to its metabolites. Novocaine passes through mucous membranes poorly, so it is rarely used for superficial anesthesia (sometimes for these purposes it is used in otorhinolaryngology in high concentrations - 10% solutions). Novocaine, unlike cocaine, does not constrict blood vessels. Their tone does not change or decreases slightly, so adrenergic agonists (for example, adrenaline) are often added to novocaine solutions. By constricting blood vessels and slowing down the absorption of novocaine, adrenergic agonists enhance and prolong its anesthetic effect, and also reduce its toxicity.
With its resorptive effect, novocaine has a predominantly inhibitory effect on the nervous system. Has moderate analgesic activity. In large doses, it can cause seizures.
The effect of novocaine on the cardiovascular system is manifested by a hypotensive effect (the result of the inhibitory effect of the drug on the central nervous system and sympathetic ganglia), as well as a short-term antiarrhythmic effect (the effective refractory period and conduction time through the conduction system of the heart increase, excitability and automaticity decrease).
In the body, novocaine is quite quickly hydrolyzed by plasma and tissue esterases. Its main metabolites are diethylaminoethanol and para-aminobenzoic acid. It should be taken into account that the latter is a competitive antagonist of antibacterial agents from the sulfonamide group. The transformation products of novocaine are excreted by the kidneys.
Salicylic acid and its derivatives. Salicylic acid belongs to the group of phenolic acids. As a compound with an ortho arrangement of functional groups, it decarboxylates when heated to form phenol.
Salicylic acid is moderately soluble in water, gives intense coloration with iron (III) chloride, on which the qualitative detection of the phenolic hydroxyl group is based. Salicylic acid exhibits antirheumatic, antipyretic and antifungal effects, but as a strong acid (pKa 3.0) it causes irritation of the gastrointestinal tract and is therefore used only externally. Its derivatives - salts or esters - are used internally.
Salicylic acid is capable of forming derivatives of each functional group. Of practical importance are sodium salicylate, esters on the carboxyl group - methyl salicylate, phenyl salicylate (salol), as well as on the hydroxyl group - acetylsalicylic acid (aspirin).
The listed derivatives (except salol) have analgesic, antipyretic and anti-inflammatory effects. Methyl salicylate is used externally in ointments due to its irritating effect. Salol is used as a disinfectant for intestinal diseases and is notable for the fact that it does not hydrolyze in the acidic environment of the stomach, but disintegrates only in the intestines. In this regard, salol is also used as a material for the protective shells of some drugs that are unstable in the acidic environment of the stomach.
Salicylic acid was first obtained by oxidizing salicylic aldehyde contained in the meadowsweet plant (genus Spireae). Hence its original name - spiric acid, from which the name aspirin is associated (the initial letter "a" stands for acetyl). Acetylsalicylic acid is not found in nature.
Among other salicylic acid derivatives, n-aminosalicylic acid (PAS) is of great importance as an anti-tuberculosis agent. PAS is an antagonist of p-aminobenzoic acid, which is necessary for the normal functioning of microorganisms.
Sulfanilic acid and its derivatives. Sulfanilic (p-aminobenzenesulfonic) acid exists as a dipolar ion.
Sulfanilic acid amide (sulfonamide), known as streptocide, is the founder of a group of drugs with antibacterial activity called sulfonamides.
All sulfonamides contain the sulfonamide group -SO2NH2. Replacing it with other groups leads to loss of antibacterial activity. It has been established that the amino group in the para position must remain unsubstituted, and additional substituents cannot be introduced into the benzene ring, since they reduce the antibacterial activity of the compound.
The bacteriostatic effect of sulfonamides is based on their structural similarity to para-aminobenzoic acid (PABA), which is necessary for the life of microorganisms. In environments where there is a lot of PABA (pus, a site of tissue decay), sulfonamides are ineffective. For the same reason, they have little effect in the presence of procaine (novocaine) and benzocaine (anesthesin), which hydrolyze to form PABA.
Streptocide is one of the first antimicrobial drugs with a sulfonamide structure, from which the name of this entire class comes. Currently not used due to low efficiency and toxicity.
In the search for effective antibacterial agents, more than 10 thousand sulfonamide derivatives were synthesized. However, only a few dozen of them have found practical application. Those derivatives in which the radical R is of a heterocyclic nature exhibit the greatest activity.
List of used literature and information:
Bioorganic chemistry: textbook N. A. Tyukavkina, Yu. I. Baukov.
Pathophysiology: textbook: in 2 volumes / ed. V.V. Novitsky, E.D. Goldberg, O.I. Urazova. - 4th ed.,
Pharmacology: textbook. - 10th ed., revised, revised. and additional - M.: GEOTAR-Media,
SULPHANAMIDES, L. S. Strachunsky, S. N. Kozlov. Guide for doctors
Salicylic (o-hydroxybenzoic acid) exhibits the properties of carboxylic acids and phenols. It is a stronger acid than benzoic acid. Salicylic acid exhibits an antipyretic and antirheumatic effect, but as a strong acid it has an irritating effect on the gastrointestinal tract and is not used for internal use.
The increased acidic properties of salicylic acid are associated with the stability of its anion, stabilized by the formation of an intramolecular hydrogen bond:
Salicylic acid forms salts when reacting with alkalis and sodium bicarbonate:
To obtain phenyl salicylate, the carboxyl group of salicylic acid is pre-activated (phenols are not acylated by carboxylic acids due to their reduced nucleophilicity):
Acetylsalicylic acid has antipyretic and anti-inflammatory effects.
If stored improperly (high humidity and temperature), acetylsalicylic acid can hydrolyze, i.e. an admixture of free salicylic acid appears in the drug.
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This drug cannot be used, because salicylic acid irritates the gastrointestinal mucosa and has an ulcerogenic effect. The good quality of acetylsalicylic acid (i.e., the absence of salicylic acid impurities in it) can be determined using a qualitative reaction to phenolic hydroxyl. If a violet color appears upon interaction with iron (III) chloride, the drug is of poor quality.
Of the salicylic acid derivatives, p-aminosa- is also used in medicine.
licylic acid (PAS). It is used in the treatment of tuberculosis and acts as a p-aminobenzoic acid antagonist (see page 129).
Salicylic acid
Chemical formula of the product: C 7 H 6 O 3 / HOC 6 H 4 COOH
Product trade names:
O-Hydroxybenzoic acid
Phenol-2-carboxylic acid
Salonil
2-Hydroxybenzoic acid
2-Hydroxybenzenecarboxylic acid
2-Carboxyphenol
O-Carboxyphenol
Product Description:
Salicylic acid - white crystalline powder or needle-shaped crystals with a sweetish taste; Soluble in acetone, ether, alcohol, boiling water, benzene and turpentine, rarely soluble in chloroformbenzene, slightly soluble in water; Melts at 158°C. Form sodium salt (sodium salicylate) is a common one, obtained mainly from sodium phenolate with carbon dioxide under heat and pressure. Salicylic acid contains both a hydroxyl and a carboxyl group, which react with either acid or alcohol. The carboxyl group forms esters with alcohols; For example, methyl salicylate is formed with methanol, which is used in food flavorings and preservatives; Menthyl salicylate is formed with methanol, which is used in tanning lotions. The hydroxyl group reacts with acetic acid to form acetylsalicylic acid(so-called aspirin), which is the most common antiseptic and antipyretic agent. Phenyl salicylate (called salol) is formed by phenol, which is also used as an antiseptic and antipyretic. Sodium salt (sodium salicylate), a shiny white powder, used for antiseptic preparations and as a preservative. In addition to its analgesic and antipyretic properties, salicylic acid has keratinolytic properties and fungicidal properties. It and its derivatives are used in the treatment of hyperkeratosis, dandruff, ichthyosis and psoriasis, as well as in the treatment of fungal skin infections such as herpes zoster. Para-aminosalicylic acid (abbreviated PAS and PASA) is an analogue of para-aminobenzoic acid (abbreviated PABA), which inhibits the synthesis of folic acid in Mycobacterium tuberculosis and is bacteriostatic, inhibiting the growth and reproduction of tubercle bacilli. Para-aminosalicylic acid and its sodium salt (sodium p-aminosalicylate) are bacteriostatic against mycobacteria and are used to treat tuberculosis; Orally. Aminosalicylic acids are pharmaceutically active ingredients, including anti-infectives against colds, flu and other viral infections. Mesalamine (5-aminosalicylic acid, abbreviated 5-ASA) is an active metabolite of sulfasalazine used to treat inflammation of the rectum and lower colon, proctosigmoiditis, mild to moderate ulcerative colitis, and proctitis. Para-aminosalicylic acid (4-hydroxybenzoic acid) is used as a bacteriostatic intermediate, especially for arabens (alkyl esters of p-hydroxybenzoic acid), which are used in food and personal care products as a preservative. It is used in the production of liquid crystal polymers. It is also used as an intermediate in dyes, insecticides, pharmaceuticals, pesticides and other chemical compounds. Salicylic acid and its derivatives are important for the preparation of other pharmaceutical products, dyes, flavors and preservatives. Topical keratolytic agents are beta hydroxy acids such as salicylic acid.
If you have heard about salicylic acid, chances are you know it as the main ingredient in aspirin. The chemical got its name from the Latin term for willow, salix, because it was first made from a complex carbohydrate found in willow bark. There are some companies that make acne care products claiming to contain salicylic acid from willow bark, but the compound is not found in tree bark. Powdered bark must be treated with oxidizing agents and filtered to obtain acid. Salicylic acid is a very useful pain reliever. For a while, researchers even speculated that it might be a vitamin, which they called vitamin C. Inside the Body salicylic acid relieves pain and improves blood circulation. When applied to the skin, it breaks down oily compounds such as oily sebum that can clog pores. In fact, it is so good at breaking down fats and oil-like compounds in the skin that it is generally believed that more than 2% is used on the face. salicylic acid, with 98% of the lotion being a neutral carrier. Until 3% salicylic acid can be used on other parts of the body, and 10% to 30% will dissolve warts. Using a soft solution salicylic acid directly on the skin offers many of the benefits of cleansing, without the risk of tearing pores or damaging tiny blood vessels. However, treatment salicylic acid has many benefits that a simple cleaning procedure does not. Gently removing dead skin does more than just open pores. Salicylic acid increases cell turnover. This causes the skin to grow faster, opening up the pores. It increases collagen production, filling cavities in the skin and making it less “flexible.” It removes discoloration from skin, although it is often too strong to use on dark skin. Salicylic acid is the only beta hydroxy acid used in skin care. It performs the same skin care tasks as alpha hydroxy acids such as lactic acid and glycolic acid, but is used in a much weaker concentration. Acne care products can contain up to 30% alpha hydroxy acids, but the same effect is achieved with 0.5% to 2% salicylic acid. Similar to benzoyl peroxide salicylic acid It is most effective only when used continuously even after the acne has cleared. In the absence of exfoliating and cleansing action salicylic acid pores can become clogged again, causing acne to return. Salicylic acid also used in many acne treatments as combination therapy at low concentrations. The exfoliating effect of the acid helps enhance the effectiveness of other active ingredients. Because salicylic acid is effective at low concentrations, it is significantly less irritating than other products.
Chemical peeling is a safe, effective and economical procedure for treating various skin diseases and improving appearance. Principle peeling involves controlled chemical damage to the skin to induce skin rejuvenation, resulting in smoother skin and improved surface texture. Chemical peeling can be classified in different ways. A useful approach is to classify them according to the degree of skin damage, which determines the indications they can be used for treatment. Respectively, chemical peeling can be divided into three broad categories, i.e. superficial, mid-depth and deep. Superficial peelings cause damage to the epidermis and are therefore used to treat superficial conditions, including melasma, acne and dyschromia. Medium depth peels penetrate the papillary dermis and are useful in the treatment of solar keratoses, dyschromia and pigment disorders. Deep peels cause necrosis down to the level of the reticular dermis, so they are indicated for deep wrinkles, severe photoaging and deep scars. Salicylic acid is part of a group of compounds known as hydroxy acids, which are widely used for a number of cosmetic indications due to their many important properties. Its mechanism of action is desmolytic rather than a true keratolytic and is safe in dark-skinned individuals. Chemical peeling is the process of causing controlled chemical damage to the skin (partial or complete epidermis with or without dermis) by applying a chemical peel that causes the superficial layers of the skin to peel off, resulting in the removal of superficial lesions followed by the regeneration of new epidermal and dermal tissues. Salicylic acid is generally a safe compound when used in appropriate concentrations for the treatment of acne. However, one thing you may notice with salicylic acid based acne products is that they can sometimes leave your skin a little dry. So, it goes without saying that you should avoid any harsh cleansers or astringents when using salicylic acid products. It's important to make sure you have a balanced acne treatment regimen, especially if you're using salicylic acid-based products. Make sure you moisturize your skin regularly and use soothing products when using salicylic acid. Also, make sure you don't apply salicylic acid For large areas of your skin, stick to areas that have acne. If your skin is damaged, swollen, red, or infected, avoid using salicylic acid-based products.
Physico-chemical properties Salicylic acid.
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Indicators |
Meaning |
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State of aggregation Salicylic acid |
crystalline powder |
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Color Salicylic acid |
White to pale yellow |
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Melting point Salicylic acid |
158-161 ° C |
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Boiling point Salicylic acid |
211°C |
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Density Salicylic acid |
1,44 |
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Vapor Density Salicylic acid |
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Vapor pressure Salicylic acid |
1 mmHg Art. (114°C) |
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Solubility: ethanol: 1 M at 20°C |
transparent, colorless |
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Solubility in water |
1.8 g/l (20 °C) |
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pH level Salicylic acid |
Storage and transportation Salicylic acid.
Salicylic acid has the ability to destroy lipids in the skin, causing symptoms ranging from dryness and irritation at low concentrations to mild acid burns at higher concentrations. If ingested in large quantities, it can cause salicylate toxicity, which can lead to very serious side effects.
No special storage is required; salicylic acid can be stored in any clean container. Keep closed. Keep away from heat. Keep away from sources of ignition. Empty containers pose a fire hazard; evaporate residues using a hood. Ground all equipment containing the material. Do not swallow. Do not inhale dust. Wear appropriate protective clothing. In case of insufficient ventilation, wear suitable respiratory equipment. If swallowed, seek immediate medical attention and show container or label. Avoid contact with skin and eyes. Keep away from incompatible substances such as oxidizing agents, moisture.
Product Application Areas .
Salicic acid used as an anti-aging agent
Salicic acid It is used as a remedy for poisoning by certain poisons.
Salicic acid used as a means to remove warts and other skin defects.
Salicic acid used as a cosmetic biocide.
Salicic acid used as denatured alcohol.
Salicic acid used as an exfoliant.
Salicic acid used as an external analgesic.
Salicic acid used as a flavoring agent.
Salicic acid Used as a skin conditioner.
Salicic acid used as a preservative.
Salicic acid used as an agent in hair conditioning products.
Salicic acid used as a solvent.
Salicic acid used as an agent in sun protection creams.
Salicic acid used in the production of ultraviolet light absorption products.
Salicylic acid group drugs are classic antirheumatic drugs. In addition to anti-inflammatory, they have a pronounced antipyretic and analgesic effect. The anti-inflammatory effect of salicylic drugs is not associated with an antimicrobial effect, but perhaps depends on their ability to stimulate the release of adrenocorticotropic hormone by the anterior pituitary gland. This hormone, in turn, enhances the secretion of hormones from the adrenal cortex, which have a powerful anti-inflammatory effect.
Salicylic acid- orthohydroxybenzoic acid - C 6 H 4 (OH) COOH - has a pronounced antimicrobial (antiseptic) effect (see Antiseptics). When exposed to the skin, it has a keratoplastic effect in low concentrations, and a keratolytic effect in high concentrations. The keratolytic effect refers to the ability of a substance to loosen the stratum corneum of the epidermis and cause its rejection. The keratoplasty effect is to stimulate the growth of the skin epithelium. When applied externally, salicylic acid reduces sweat secretion. The local effect of salicylic acid on the skin is used in the treatment of various skin diseases, in particular to combat hyperkeratosis (calluses) and excessive sweating. When taken orally, salicylic acid causes irritation of the gastric mucosa, so it is often used in the form of a sodium salt. Salicylic acid is well absorbed from the gastrointestinal tract and has antipyretic, analgesic and anti-inflammatory effects. Salicylic acid is quickly released from the body. Most of it is released during the first day. Salicylic acid is released through the kidneys and sweat glands. When excreted through the kidneys, salicylic acid causes increased urination and the excretion of uric acid in the urine.
Salicylic acid and its salts have low toxicity and are quite well tolerated by patients. However, due to the fact that in the treatment of rheumatism, salicylates are prescribed in very large quantities, they can still cause poisoning phenomena: tinnitus, hearing loss, intoxication, shortness of breath, and sometimes skin rashes. These phenomena easily go away when you stop using salicylates.
Aspirin- acetylsalicylic acid - C6H4(OCOCH3)COOH - is widely used as an antipyretic and analgesic. In some countries it is widely used for the treatment of rheumatism. In the gastrointestinal tract, aspirin is partially saponified to form salicylic and acetic acids. Part of it is absorbed unchanged.
Methyl salicylate- salicylic acid methyl ester - - is a liquid that is well absorbed by the skin. It is used as an external rub for the treatment of rheumatic and neuralgic pain, often in combination with other remedies. Methyl salicylate has both local and resorptive effects.
Drugs
Phenacetin(Phenacetinum), FVIII. White crystalline powder or scaly crystals, odorless, slightly bitter in taste, almost insoluble in water. It is used orally in powders or tablets of 0.25-0.5 g per dose 1-3 times a day, depending on the indications. Often combined with other antipyretics or sedatives, as well as caffeine.
Antipyrine(Antipyrmum), FVIII (B). White crystalline powder, odorless, slightly bitter taste, highly soluble in water. It is used orally in powders or tablets of 0.25-0.5 g 1-3 times a day. Often used in combination with other agents. To stop bleeding, it is used externally in 10-20% solutions.
Higher doses: 1 g (3 g).
Pyramidon(Pyramidonum), FVIII (B). White crystalline powder, odorless, bitter taste, soluble in water. It is used orally in powders and tablets of 0.25-0.5 g 1-3 times a day. Often combined with other drugs. Its combination with veronal (1 mol: 2 mol) is called verodona.
Higher doses: 0.5 g (1.5 g).
Analgin(Analginum), FVIII (B). White crystalline powder, odorless and tasteless, highly soluble in water. Analgin solutions are unstable during storage. It is used orally in powders or tablets of 0.3-0.5 g and parenterally (subcutaneously, intramuscularly or intravenously) 0.5 g 1-3 times a day.
Higher doses: 1 g (3 g).
Butadion(Butadionum) (B). White crystalline powder with a weak aromatic odor and slightly bitter taste, almost insoluble in water, soluble in alkalis. It is used orally in powders or tablets of 0.15 g 4 times a day during the main course of treatment. Maintenance doses are 0.1-0.2 g per day. Butadione sodium salt can be used for intramuscular injections, although they are somewhat painful. A solution containing sodium salt of butadione and pyramidone in equal quantities is convenient for injection.
Sodium salicylate(Natrium salicylicum), FVIII. White crystalline powder or flakes, odorless, sweetish-salty taste, highly soluble in water. The drug is taken orally in powders, tablets or solutions, and is also administered intravenously in 10-15% solutions. A single dose of sodium salicylate is 0.5-1 g, the daily dose in the initial period of treatment of rheumatism can be 8-10 g. Subsequently, the dose is reduced. The total duration of treatment varies.
Aspirin(Aspirinum), FVIII. White needle-shaped or plate-shaped crystals, slightly sour taste, slightly soluble in water. Taken orally in powders and tablets, 0.3-0.5 g per dose 2-4 times a day.
Methyl salicylate(Methylium salicylicum), FVIII. A colorless or yellowish liquid with a characteristic aromatic odor, insoluble in water, miscible in all respects with common organic solvents. Apply externally for rubbing, per se or in liniments.
