Pyrithiones

Medicated Dandruff Shampoos. Dandmff is a scalp condition characterized by the production of excessive cellular material (18). A number of shampoos have been marketed which are designed to control and alleviate this condition, and many additives have been included in shampoo compositions to classify them as treatment products for dandmff. These additives include antimicrobial additives, eg, quaternary ammonium salts keratolytic agents, eg, saUcychc acid and sulfur heavy metals, eg, cadmium sulfide coal tar resorcinol and many others. More recent (ca 1993) systems use selenium sulfide [7488-56-4] or zinc pyrithione [13463-41 -7] as active antidandmff shampoo additives. Both of these additives are classified as dmgs, but can be found in over-the-counter products. A stronger version, incorporating the use of higher levels of selenium sulfide in a shampoo, is available but requires a prescription for purchase. 

Textile Finishing. Polyethyleneimine-A/-methylolurea derivatives improve the crease and wear resistance of cotton (429,430). The adhesion between individual wool fibers is improved by pretreatment with amines, which leads to improved shrink resistance (431). An antimicrobial finish can be appHed to cotton by using a combination of PEI and ureas to bind zinc pyrithione to the fabric (432). After wool has been provided with a flameproof finish using fluorozirconate or fluorotitanate, the wool can be neutralized with PEI (433). Conventional neutralizing agents caimot be used for this purpose since they impair the flameproof characteristics of the impregnated fabric. 

Chloropyridine N-oxide reacts with sodium hydrosulfide to give pyrithione [1121-31-9] (45), the zinc salt of which is used as an... 

Pyridine A Oxides. Analgesic and antiinflammatory dmgs niflumic acid [4394-00-7] (68) and pranoprofen [52549-17-4] (69) are manufactured from nicotinic acid N-oxide [2398-81 -4]. The antiulcer dmg omeprazole (66) is produced from 2,3,5-trimethylpyridine N-oxide [74409-42-0]. Zinc pyrithione, the zinc salt of pyrithione (45), is a fungicide derived from 2-chloropyridine N-oxide (45). 

Mercaptopyridine iV-oxide sodium salt (pyridinethione or pyrithione sodium salt) [3811-73-2] M 149.1, m 250°(dec), pK] -1.95, pK2 4.65. When recrystd from water it assayed as 98.7% based on AgNO titration [Krivis et al. Anal Chem 35 966 1963, see also Krivis et al. Anal Chem 4 1001 1976 and Barton and Crich J Chem Soc. Perkin Trans I 1603, 1613 1986]. 

C5H4CIN 109-09-1) see Brompheniramine Chlorphenamine Disopyramide Methylphenidate Pheniramine Pyrithione zinc Rosiglitazone Trazodone 4-chloropyridine... 

C7H,j05S 97-05-2) see Domiodol 3-sulfo-2-thiophenecarboxylic acid (C5H4O5S2 59337-95-0) see Tenoxicam sulfuric acid zinc salt (1 1) heptahydrate (H 405SZn 7446-20-0) see Pyrithione zinc... 

The other major fungicide used in metalworking fluids is sodium pyrithione (Figure 9). 

Sodium potassium tripolyphosphate (SKTP), 28 846 Sodium production, 9 640 Sodium pyrithione... 

Isomerization calciferol chlorprothixene cholecalciferol clomiphene clopenthixol pyrithione reserpine sulpyrine tetracycline... 

Reduction chloramphenicol cinchonidine cinchonine nitrazepam physostigmine pyrithione quinidine quinine benzoxaprofen chlortetracycline demeclocycline dithranol menadione mercaptopurine methotrexate nalidixic acid oxolinic acid... 

In spite of these disadvantages, some of which appear to be already overcome (Anderson et al., 2003), many successful case-stories of the use of foul-release coatings are available on fast-moving vessels and propellers (Anderson et al., 2003). However, the existence of powerful broad-spectrum synthetic biocides with satisfactory degradation profiles in sea water (e.g. Sea-Nine 211, Zn- and Cu- pyrithiones Yebra et al., 2004) means that chemically-active antifouling coatings will probably dominate the bulk market of AF paints for seagoing vessels for many years to come (Yebra et al., 2004). 

In this example the TON was not optimized. However, the catalytic reaction [Eq.(28) ] seems to offer an easy entry into the pyrithione systems. The classical access to this is given in Eq.(29). 

Zinc is used for a variety of indications. Zinc acetate (8.102) or, rarely, zinc sulfate (8.103) have been used orally to treat Wilson s disease, a recessively inherited disorder of copper metabolism, characterized by brain and liver dysfunction arising from excessive deposits of copper. Zinc pyrithione (8.104) is used in shampoos to treat seborrhea. Zinc propionate (8.105) and zinc caprylate (8.106) have been used as topical antifungal agents. 

Pyrithione zinc, 1-2% shampoo, apply once or twice weekly Denorex Daily, Head Shoulders, Sebulon, various generic Both selenium sulfide and zinc pyrithione are cytostatic agents that decrease epidermal turnover rates. Massage into wet scalp for 2-3 minutes. Rinse thoroughly and repeat application. Selenium sulfide can be irritating to the eyes and skin. 

Pyrithione (zinc salt of) is used as a component of antidandruff shampoos and as a bactericide in soap and detergent formulations. This compound (2-mercaptopyridine N-oxide) exists in equilibrium with N-hydroxy-2-pyridinethione and is a fungicide and bactericide, prepared by reaction of 2-chloropyridine N-oxide with sodium hydrosulfide and sodium sulfide. This compound is also known as Omadine, Its formula is shown below. 

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