4-Hydroxybenzoic acid ethyl ester

Reference Standard 4-Hydroxybenzoic acid ethyl ester. Sample Solution A solution of 10 g of sample per liter of deionized water. 

Procedure (See Chromatography, Appendix IIA.) Use a high-performance liquid chromatograph capable of separating acesulfame potassium and 4-hydroxybenzoic acid ethyl ester with a resolution of 2. Use a chromatograph equipped with a UV or diode array (227 nm) detector and a 25-cm x 4.6-mm (id) stainless steel column, or equivalent, packed with 3 to 5 p,m of reversed phase C18 silica gel, or equivalent. The elution is isocratic. Use a 40 60 (v/v) solution of acetoni-trile 0.01 MlL tetrabutyl ammonium hydrogen sulfate (TBAHS) in water as the mobile phase, with a flow rate of about 1 mL/min. 

Donsbach [2] prepared 3,3-diarylpropylamines by hydroformylation/hydro-carbonylation followed by reductive amination using (acetylacetonate)dicar-bonylrhodium as illustrated below, beginning with 4-hydroxybenzoic acid, ethyl ester. 

Dietmhoxybenzoic acid, ethyl ester 3-Methoxy-4-hydroxybenzoic acid, ethyl ester... 

CAS 617-05-0 EINECS/ELINCS 210-503-9 Synonyms m-Anisic acid, 4-hydroxy-, ethyl ester Benzoic acid, 4-hydroxy-3-methoxy-, ethyl ester Ethyl 4-hydroxy-3-methoxybenzoate Ethyl 3-methoxy-4-hydroxybenzoate 3-Methoxy-4-hydroxybenzoic acid, ethyl ester... 

Hydroxybenzoic acid, ethyl ester, sodium salt. 

Synonyms Ethylparaben, sodium salt 4-Hydroxybenzoic acid, ethyl ester, sodium salt Sodium 4-ethoxycarbonylphenoxide Sodium ethyl 4-hydroxybenzoate Sodium ethyl p-hyd roxy benzoate... 

Synonyms ethyl-4-hydroxybenzoate ethylparaben ethyl p-hydroxybenzoate 4-hydroxybenzoic acid ethyl ester Nipagin A ethyl parasept Solbrol A p-hydroxybenzoic acid ethyl ester... 

Ethyl Salicylate. 2 Hydroxybenzoic acid ethyl ester Salicylic acid ethyl ester salicylic ether sal ethyl. C,H. Oj mol wt 166.17. C 65.05%, H 6.07%, O 28.88%. HOC4H4COOCjH5. 

Synonyms cas 90-2-8 salicylaldehyde salicylic aldehyde 2-formylphenol salicylal p-Hydroxybenzoic Acid Ethyl Ester... 

Among the derivates of HBAs, further compounds have been identified. GUntert et al. (1986) identified ethyl esters of vanillic acid and p-hydroxybenzoic acid, and methyl esters of vanillic acid and protocatechuic acid. Ethyl esters of protocatechuic acid and vanillic acid, as well as the glucose ester of vanillic acid, were isolated from a German Riesling wine (Baderschneider and Winterhalter 2001). Analytically, HBA are mostly determined as trimethylsilane derivatives by using... 

HYDROXYBENZOIC ACID see HJIIOO m-HYDROXYBENZOIC ACID see HJIIOO o-HYDROXYBEXZOIC ACID see SAIOOO p-HYDROXYBEXZOIC ACID ETHYL ESTER see HJLOOO... 

E214 ethyl p-hydroxybenzoate Ethyl parasept 4-hydroxy-benzoic acid ethyl ester Solbrol A-, Tegosept E. 

H.78) Benzoic acid, 2-hydroxy-, ethyl ester, ethyl 2-hydroxybenzoate, ethyl salicylate, salicylic acid ethyl ester [118-61-6] FEMA 2458... 

Beilstein Handbook Reference) AI3-00513 Benzoic acid, 2-hydroxy-, ethyl ester BRN 0907659 EINECS 204-265-5 o-(Ethoxycarbonyl)phenol Ethyl 2-hydroxybenzoate Ethyl o-hydroxybenzoate Ethyl salicylate PEMA No. 2458 Mesotol NSC 8209 Sal ether Sal ethyl Salicylic acid, ethyl ester Salicylic ether Salicylic ethyl ester Salotan. Used in perfumery has been used in veterinary medicine as a counter-irritant. Crystals mp = 45° bp = 231-234°, bpio = 150-151° d = 1,1326 Xm = 238, 305 nm (c = 13800, 6590, MeOH) insoluble in H2O, soluble in CCI4, very soluble in Et20, freely soluble in EtOH,... 

Benzoic acid ethyl ester. See Ethyl benzoate Benzoic acid, 4-(((ethylphenylamino) methylene) amino)-, ethyl ester. See N-(p-Ethoxycarbony I phenyl )-N -ethy l-N -phenylformamidine Benzoic acid, hexahydro-. See Cyclohexanecarboxylic acid Benzoic acid, hexyl ester. See Hexyl benzoate Benzoic acid, 4-hydroxy- Benzoic acid, p-hydroxy-. See 4-Hydroxybenzoic acid Benzoic acid, 2-hydroxy-, butyl ester. See Butyl salicylate... 

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 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). 

Liquid dosage forms which are disperse systems (colloidal, i.e., microspheres, nanoparticles, and micelles suspensions and emulsions) often contain preservatives which are methyl, ethyl, propyl, and butyl esters of para-hydroxybenzoic acid in various combinations. A typical example is the antacid suspensions which have high pH values which make the esters of the preservatives susceptible to hydrolysis. One way to circumvent this problem is to use several preservatives in combination with the hope that some quantities of the preservatives will remain to prevent the suspension from microbial attack. A report showing the assay of the four esters and the parent acid (one of the decomposition products) in drug products in which all the preservatives were used has been given [13]. 

These compounds include the methyl, ethyl, propyl, and butyl esters of para-hydroxybenzoic acid. In the United Slates and a number of other countries, the methyl and propyl esters are preferred, while European food processors favor the ethyl and butyl esters. The parabens were first described in 1924 as having antimicrobial activity and initially were used in cosmetic and pharmaceutical products. 

This part of the chapter describes HPLC techniques for the separation and determination of preservatives, as follows S02, postharvest preservatives (PPs), benzoic acid (BA), sorbic acid (SA), and the ethyl, methyl, propyl esters of 4-hydroxybenzoic acid (EsHBA) and 5-nitrofury-lacrylic acid (5-NFA). The propionic, lactic, acetic acids are discussed in the chapter on organic acids. 

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