Zinc pyrithione dimer | |
Names | |
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IUPAC name bis(2-pyridylthio)zinc 1,1'-dioxide | |
Other names ZnP, Pyrithione Zinc, Zinc OMADINE, ZnPT | |
Identifiers | |
3D model (JSmol) |
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ChEMBL | |
ChemSpider | |
ECHA InfoCard | 100.033.324 |
PubChem CID | |
UNII | |
CompTox Dashboard (EPA) | |
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Properties | |
C10H8N2O2S2Zn | |
Molar mass | 317.70 g/mol |
Appearance | colourless solid |
Melting point | 240 °C (464 °F; 513 K) (decomposition) [1] |
Boiling point | decomposes |
8 ppm (pH 7) | |
Pharmacology | |
D11AX12 ( WHO ) | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Zinc pyrithione (or pyrithione zinc) is a coordination complex of zinc. It has fungistatic (inhibiting the division of fungal cells) and bacteriostatic (inhibiting bacterial cell division) properties and is used in the treatment of seborrhoeic dermatitis [2] and dandruff.
The pyrithione ligands, which are formally monoanions, are chelated to Zn2+ via oxygen and sulfur centers. In the crystalline state, zinc pyrithione exists as a centrosymmetric dimer (see figure), where each zinc is bonded to two sulfur and three oxygen centers. [3] In solution, however, the dimers dissociate via scission of one Zn-O bond.[ citation needed ]
This compound was first described in the 1930s. [4]
Pyrithione is the conjugate base derived from 2-mercaptopyridine-N-oxide (CAS# 1121-31-9), a derivative of pyridine-N-oxide.[ citation needed ]
Zinc pyrithione can be used to treat dandruff and seborrhoeic dermatitis. [5] [6] [7] It also has antibacterial properties and is effective against many pathogens from the Streptococcus and Staphylococcus genera. [8] Its other medical applications include treatments of psoriasis, eczema, ringworm, fungus, athletes foot, dry skin, atopic dermatitis, tinea versicolor, [9] [8] and vitiligo.[ medical citation needed ]
Because of its low solubility in water (8 ppm at neutral pH), zinc pyrithione is suitable for use in outdoor paints and other products that protect against mildew and algae. It is an algaecide. It is chemically incompatible with paints relying on metal carboxylate curing agents. When it is used in latex paints with water containing much iron, a sequestering agent that preferentially binds the iron ions is needed. It is decomposed by ultraviolet light slowly, providing years of protection in direct sunlight.[ citation needed ]
Zinc pyrithione is an antibacterial treatment for household sponges, as used by the 3M Corporation. [10] [11]
A process to apply zinc pyrithione to cotton with washable results was patented in the United States in 1984. [12] Zinc pyrithione is used to prevent microbe growth in polyester. [13] Textiles with applied zinc pyrithione protect against odor-causing microorganisms. Export of antimicrobial textiles reached US$497.4 million in 2015. [14]
Zinc pyrithione is known to exhibit antibacterial activity by disrupting cell membrane integrity and essential metabolic functions in bacteria. [15]
Its antifungal effect is thought to derive from its ability to disrupt membrane transport by blocking the proton pump that energizes the transport mechanism. [16] A study from 2011 showed that antifungal effects of Zinc pyrithione work by copper toxicity mechanism that targets critical iron–sulphur proteins. [17]
Zinc pyrithione is approved for over-the-counter topical use in the United States as a treatment for dandruff and is the active ingredient in several anti-dandruff shampoos and body wash gels. In its industrial forms and strengths, it may be harmful by contact or ingestion. Zinc pyrithione can in the laboratory setting trigger a variety of responses, such as DNA damage in skin cells. [18]
Use of zinc pyrithione is prohibited within cosmetic products in the European Union since December 2021. [19] The substance was considered safe for use in rinse-off and leave-in products of different tested concentrations, but due to potential environmental toxicity consideration of the use of zinc pyrithione was made against potential alternative substance ingredients. Due to no industry submission to the regulators supporting the continued use of zinc pyrithione and/or an absence of indications that there were no suitable alternatives to the substance: the use of zinc pyrithione became automatically prohibited within cosmetic products as an intended ingredient. This was as a consequence of zinc pyrithione addition to the Cosmetic Product Regulation (EC) No 1223/2009 Annex II list. [19]
Zinc pyrithione concentration of up to 2% is allowed for products when they are formulated to be applied and then washed off after brief exposure. Alternatively, up to 0.25 percent when formulated to be left on the skin or scalp [20]
A large Swedish study shows that it is broken down in wastewater plants and does not release into waterways. [21] A Danish study shows that it biodegrades quickly, but that a risk of continuous leaching from boat paint may cause environmental toxicity. [22]
Dermatitis is a term used for different types of skin inflammation, typically characterized by itchiness, redness and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become thickened. The area of skin involved can vary from small to covering the entire body. Dermatitis is also called eczema but the same term is often used for the most common type of skin inflammation, atopic dermatitis.
Methylisothiazolinone, MIT, or MI, is the organic compound with the formula S(CH)2C(O)NCH3. It is a white solid. Isothiazolinones, a class of heterocycles, are used as biocides in numerous personal care products and other industrial applications. MIT and related compounds have attracted much attention for their allergenic properties, e.g. contact dermatitis.
Dandruff is a skin condition that mainly affects the scalp. Symptoms include flaking and sometimes mild itchiness. It can result in social or self-esteem problems. A more severe form of the condition, which includes inflammation of the skin, is known as seborrhoeic dermatitis.
Tinea versicolor is a condition characterized by a skin eruption on the trunk and proximal extremities. The majority of tinea versicolor is caused by the fungus Malassezia globosa, although Malassezia furfur is responsible for a small number of cases. These yeasts are normally found on the human skin and become troublesome only under certain conditions, such as a warm and humid environment, although the exact conditions that cause initiation of the disease process are poorly understood.
Seborrhoeic dermatitis is a long-term skin disorder. Symptoms include flaky, scaly, greasy, and occasionally itchy and inflamed skin. Areas of the skin rich in oil-producing glands are often affected including the scalp, face, and chest. It can result in social or self-esteem problems. In babies, when the scalp is primarily involved, it is called cradle cap. Mild seborrhoeic dermatitis of the scalp may be described in lay terms as dandruff due to the dry, flaky character of the skin. However, as dandruff may refer to any dryness or scaling of the scalp, not all dandruff is seborrhoeic dermatitis. Seborrhoeic dermatitis is sometimes inaccurately referred to as seborrhoea.
An antifungal medication, also known as an antimycotic medication, is a pharmaceutical fungicide or fungistatic used to treat and prevent mycosis such as athlete's foot, ringworm, candidiasis (thrush), serious systemic infections such as cryptococcal meningitis, and others. Such drugs are usually obtained by a doctor's prescription, but a few are available over the counter (OTC). The evolution of antifungal resistance is a growing threat to health globally.
Ketoconazole, sold under the brand name Nizoral, among others, is an antiandrogen, antifungal, and antiglucocorticoid medication used to treat a number of fungal infections. Applied to the skin it is used for fungal skin infections such as tinea, cutaneous candidiasis, pityriasis versicolor, dandruff, and seborrheic dermatitis. Taken by mouth it is a less preferred option and only recommended for severe infections when other agents cannot be used. Other uses include treatment of excessive male-patterned hair growth in women and Cushing's syndrome.
Malassezia is a genus of fungi.
Ciclopirox is a medication used for the treatment of moderate onychomycosis of fingernails and toenails, and for the treatment of seborrheic dermatitis.
Cradle cap is crusty or oily scaly patches on a baby's scalp. The condition is not painful or itchy, but it can cause thick white or yellow scales that are not easy to remove. Cradle cap most commonly begins sometime in the first three months but can occur in later years. Similar symptoms in older children are more likely to be dandruff than cradle cap. The rash is often prominent around the ear, the eyebrows or the eyelids. It may appear in other locations as well, where it is called infantile seborrhoeic dermatitis. Cradle cap is just a special—and more benign—case of this condition. The exact cause of cradle cap is not known. Cradle cap is not spread from person to person. It is also not caused by poor hygiene. It is not an allergy, and it is not dangerous. Cradle cap often lasts a few months. In some children, the condition can last until age 2 or 3.
Selenium disulfide, also known as selenium sulfide, is a chemical compound and medication used to treat seborrheic dermatitis, dandruff, and pityriasis versicolor. It is applied to the affected area as a lotion or shampoo. Symptoms frequently return if treatment is stopped.
Sulfacetamide is a sulfonamide antibiotic commonly used in the treatment of bacterial infections, particularly those affecting the eyes and skin. It functions by inhibiting the synthesis of folic acid in bacteria, which is essential for their growth and reproduction, thereby exerting a bacteriostatic effect. Available in various forms, including eye drops, topical solutions, and creams, sulfacetamide is often prescribed for conditions such as conjunctivitis, seborrheic dermatitis, and acne vulgaris. Its efficacy, coupled with a relatively low risk of side effects, makes it a widely utilized agent in both ophthalmic and dermatologic care.
Malassezia furfur is a species of yeast that is naturally found on the skin surfaces of humans and some other mammals. It is associated with a variety of dermatological conditions caused by fungal infections, notably seborrhoeic dermatitis and tinea versicolor. As an opportunistic pathogen, it has further been associated with dandruff, malassezia folliculitis, pityriasis versicolor (alba), and malassezia intertrigo, as well as catheter-related fungemia and pneumonia in patients receiving hematopoietic transplants.
Isothiazolinone (; sometimes isothiazolone) is an organic compound with the formula (CH)2SN(H)CO. A white solid, it is structurally related to isothiazole. Isothiazolone itself is of limited interest, but several of its derivatives are widely used preservatives and antimicrobials.
Shampoo is a hair care product, typically in the form of a viscous liquid, that is formulated to be used for cleaning (scalp) hair. Less commonly, it is available in solid bar format. Shampoo is used by applying it to wet hair, massaging the product in the hair, roots and scalp, and then rinsing it out. Some users may follow a shampooing with the use of hair conditioner.
Climbazole is a topical antifungal agent commonly used in the treatment of human fungal skin infections such as dandruff, seborrhoeic dermatitis and eczema. Climbazole has shown a high in vitro and in vivo efficacy against Malassezia spp. that appear to play an important role in the pathogenesis of dandruff. Its chemical structure and properties are similar to other azole fungicides such as ketoconazole, clotrimazole and miconazole.
Anti-seborrheics are drugs effective in seborrheic dermatitis. Selenium sulfide, zinc pyrithione, corticosteroids, imidazole antifungals, and salicylic acid are common anti-seborrheics.
Pyrithione is the common name of an organosulfur compound with molecular formula C
5H
5NOS, chosen as an abbreviation of pyridinethione, and found in the Persian shallot. It exists as a pair of tautomers, the major form being the thione 1-hydroxy-2(1H)-pyridinethione and the minor form being the thiol 2-mercaptopyridine N-oxide; it crystallises in the thione form. It is usually prepared from either 2-bromopyridine, 2-chloropyridine, or 2-chloropyridine N-oxide, and is commercially available as both the neutral compound and its sodium salt. It is used to prepare zinc pyrithione, which is used primarily to treat dandruff and seborrhoeic dermatitis in medicated shampoos, though is also an anti-fouling agent in paints.
Ethyl lauroyl arginate (LAE) is a food preservative, antimicrobial compound, and drug more commonly known as E243. It is used to treat dermatological disorders and is often provided in the form of its hydrochloride salt. LAE is an amino acid-based surfactant with broad-spectrum antimicrobial activity, high biodegradability and low toxicity. Due to these features, LAE is a preservative used in food and cosmetic formulations.
Topical antifungaldrugs are used to treat fungal infections on the skin, scalp, nails, vagina or inside the mouth. These medications come as creams, gels, lotions, ointments, powders, shampoos, tinctures and sprays. Most antifungal drugs induce fungal cell death by destroying the cell wall of the fungus. These drugs inhibit the production of ergosterol, which is a fundamental component of the fungal cell membrane and wall.