Ethyl 3-hydroxybenzoate

Sodium Dithionite (test), 144 Sodium ethyl hydroxybenzoate, 603 Sodium fluoroacetate, 627... 

BP Ethyl hydroxybenzoate JP Ethyl parahydroxybenzoate PhEur Ethylis parahydroxybenzoas USPNF Ethylparaben... 

Synonyms E215 ethyl 4-hydroxybenzoate sodium salt sodium ethyl hydroxybenzoate. 

Synonyms ethyl 4-hydroxybenzoate potassium salt potassium ethyl hydroxybenzoate. 

Dichlorophenol Ethyl />-hydroxybenzoate with, e.g., S02C12 (2.2 moles) in 1.5 h on the water-bath affords a yield of about 85 % of ethyl 3,5-dichloro-4-hydroxybenzoate, which is hydrolysed by methanolic potassium hydroxide to 3,5-dichloro-4-hydroxybenzoic acid. This acid (1.2 moles) in dimethylaniline (575 g) is heated gradually to 190-200° and kept at this temperature until evolution of C02 ceases (about 2 h), giving 80-90% of 2,6-dichloro-phenol. For details see Organic Syntheses 451... 

Figure 8.26 DSC curves of ethyl -hydroxybenzoate and propyl p-hydroxybenzoate in nitrogen...

Perfumes, Flavors, Cosmetics, and Soap. Many naturally occurring esters in essential oils and some synthetic esters are important fragrance and flavor compounds (61,62). They are used in perfumes, flavors, cosmetics, soaps, detergents, and air fresheners. Benzyl, butyl, ethyl, methyl, and phenyl esters of benzoic acid are used as flavors, perfumes, and food preservatives. Glyceryl 4-aminobenzoate [136-44-7] and 2-ethyUiexyl 4-dimethylaminobenzoate [21245-02-3] are used in cosmetic sunscreen preparations. Alkyl esters of 4-hydroxybenzoic acid, called parabens, have been used under various names for fungus infections of the skin, and as preservatives in lotions and creams (101). Soap and cosmetic fragrances use large amounts of amyl and benzyl saHcylate. Benzyl saHcylate [118-58-1] is also used in deodorant sprays. 2-Ethylhexyl saHcylate [118-60-5] and 2-ethylhexyl 4-methoxycinnamate [5466-77-3] are used in sunscreen formulations (102). 

The influence of NH., and CO, on the chromatographic behaviour of benzoic acid and its derivatives (o-, m-, p-hydroxybenzoic, nitrobenzoic, aminobenzoic, chlorobenzoic acids) was studied. The work was carried out by means of upgoing TLC on Sorbfil plates. Isopropanol- and ethyl acetate-containing water-organic eluents were used as mobile phases in the absence or presence of gaseous modifiers in the MP. The novel modification of TLC has been found to separate benzoic acids with different values of their dissociation constants more effectively than water-organic mobile phases. 

This with potassium hydroxide in methanol forms de-OiV-dimethylarmepavine, m.p. 86-7°, (B. HCl, m.p. 229-30°) of which the methiodide, m.p. 233-4°, on treatment with alkali decomposes into trimetHylamine and a -p-anisyl-/3-(3 4-dimethoxy- 6 - vinylphenyl) -ethylene, m.p. 79°. The latter is oxidised by permanganate in acetone to anisic and m-hemipinic acids. With ethyl sulphate and alkali, armepavine gives 0-ethylarmepavine, an oil, which permanganate oxidises to p-ethoxybenzoic acid. Armepavine is similarly oxidised to p-hydroxybenzoic acid and l-keto-6 7-dimethoxy-2-methyl-1 2 3 4-tetiahydrowoquinoline and is therefore 6 7-dimethoxy-l-p-hydroxybenzyI-2-methyI-l 2 3 4-tetrahydrowoquinoline, i.e., it is laudanosine (p. 187) with MeO. at C replaced by H and MeO at C changed to HO. ... 

The mixture was heated under reflux and a solution of 0.2 g of ethyl iodide in 5 ml of dry tetrahydrofuran was allowed to flow into the reaction medium. When the reaction started, a solution of 6.2 g of 7heated under reflux until the complete disappearance of the magnesium turnings. The reaction medium was then cooled in an ice bath, after which there was added thereto a solution in 45 ml of tetrahydrofuran of 7 g of 6-oxo-benzo[b] -benzofurano[2,3-e] oxepin. The reaction mixture was allowed to stand for 20 hours at a temperature of 20°C, and was then poured into a saturated aqueous solution of ammonium chloride maintained at a temperature of 5°C. The mixture was extracted with ether and the organic portion was washed and dried over anhydrous sodium sulfate. After evaporation of the solvent, 9.4 g of crude product were obtained, which after recrystallization from isopropanol, provided 6.7 g of pure 6-(3-dimethylam nopropyl)-8-hydroxybenzo[b] benzofurano-[2,3-e] oxepin, melting point 160°C (yield, 71 %). 

Ethy I-2-(3-hydroxy-4-ami nophenyl) propio nate Benoxaprofen Ethyl p-hydroxybenzoate Cyclomethycaine... 

C21H25O4 23637-81-2) see Gestrinone ethyl 4-hydroxybenzoic acid (QjHiqOj 120-47-8) see Gabexate ethyl (2-hydroxybenzylamino)acetate (C H,5N03 57938-78-0) -see Caroxazone... 

Fig. 10.1 p-Hydroxybenzoates (R is methyl, ethyl, propyl, butyl or benzyl). 

The use of preservative eombinations may be used to extend the range and speetrum of preservation. Thus, in the series of alkyl esters of 4-hydroxybenzoic (/ -hydroxybenzoic) acid (parabens), water solubility deereases in the order methyl, ethyl, propyl and butyl ester. By eombining these produets it is possible to aehieve a situation where both the aqueous and oil phase of an emulsion are proteeted. 

C12 to C20, primarily Ci6 to ( is), used as surface lubricants in the manufacture of food-contact articles. The method, which uses ethyl palmitate (Eastman Chemicals No. 1575 Red Label) as an internal standard, has been validated at 200 ppm total FAME [185]. Other FAME standards (methyl palmitate, methyl stearate, methyl oleate, methyl linoleate and methyl linolenate) are available (Applied Science Laboratories) [116], Worked out examples of additive determinations are given in the Food Additives Analytical Manual [116], which also describes a great many of indirect food additives, such as BHA, BHT, TBHQ, l-chloro-2-propanol, DLTDP, fatty acid methyl esters, w-heptyl-p-hydroxybenzoate, propyl-gallate, sodium benzoate, sodium stearoyl-2-lactylate, sorbitol and phenolic antioxidants. EPA methods 606 and 8060 describe the CGC separation of phthalate esters (direct injection) (cf. Figure 4.2). 

Scheme 9. N-Ras peptide synthesis employing choline esters as C-terminal protecting group. EDC 1-ethyl-3 (dimethylamino)propyl-carbodiimide hydrochloride, HOBt 1-hydroxybenzo-tri azole...

There is a recent trend towards simultaneous CE separations of several classes of food additives. This has so far been applied to soft drinks and preserved fruits, but could also be used for other food products. An MEKC method was published (Lin et al., 2000) for simultaneous separation of intense sweeteners (dulcin, aspartame, saccharin and acesulfame K) and some preservatives (sorbic and benzoic acids, sodium dehydroacetate, methyl-, ethyl-, propyl- and isopropyl- p-hydroxybenzoates) in preserved fruits. Ion pair extraction and SPE cleanup were used prior to CE analysis. The average recovery of these various additives was 90% with good within-laboratory reproducibility of results. Another procedure was described by Frazier et al. (2000b) for separation of intense sweeteners, preservatives and colours as well as caffeine and caramel in soft drinks. Using the MEKC mode, separation was obtained in 15 min. The aqueous phase was 20 mM carbonate buffer at pH 9.5 and the micellar phase was 62 mM sodium dodecyl sulphate. A diode array detector was used for quantification in the range 190-600 nm, and limits of quantification of 0.01 mg/1 per analyte were reported. The authors observed that their procedure requires further validation for quantitative analysis. 

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