Butyrate esters

Low viscosity cellulose propionate butyrate esters containing 3—5% butyryl, 40—50% propionyl, and 2—3% hydroxyl groups have excellent compatibihty with oil-modified alkyd resins (qv) and are used in wood furniture coatings (155). Acetate butyrate esters have been used in such varied apphcations as hot-melt adhesive formulations (156), electrostatically spray-coated powders for fusible, non-cratering coatings on metal surfaces (157—159), contact lenses (qv) with improved oxygen permeabiUty and excellent wear characteristics (160—162), and as reverse-osmosis membranes for desalination of water (163). 

Activity is also retained when the hydroxyl group at the 21 position is replaced by chlorine. Reaction of corticoid 44 with methanesulfonyl chloride proceeds preferentially at the 21-hydroxyl (45) due to the hindered nature of the 11-alcohol. Replacement of the mesylate by means of lithium chloride in DMF affords clobetasol propionate (46) a similar sequence starting with the 17- butyrate ester 47, via mesylate 48, should give clobetasone butyrate, (49) [11]. 

Ethyl Butyrate.—The butyric ester of ethyl alcohol has the formula... 

Linalyl Butyrate.—The butyric ester of linalol has the formula, CiflHjjOOC, CH2. CHjCHj. It resembles geranyl butyrate in odour, but is somewhat heavier. It is most useful for imparting fruity odours to flower perfumes. It is prepared by condensing the alcohol and the acid by means of sulphuric acid. 

Buttersaure, /. butyric acid, -ather, tn. ethyl butyrate pi. butyric esters, -ganing, /, butyric fermentation. pilz, tn. butyric acid bacteria. 

For the cyclization of the keto esters from 7-naphthyl-butyric esters it is advisable to use 80 per cent sulphuric acid, and to heat the mixture, with stirring, at 70-80° for one-half hour. 

Further insight into the mechanism of these complicated polymerizations is provided by studies of oligomers derived from the metallated iso-butyric ester,... 

Synthesis of the (/ )-Butyrate Esters of Secondary Alcohols hy Dynamic Kinetic Resolution Employing a Bis(tetrafluorosuccinato)-hridged Ru(II) Complex... 

A mammal may emit many volatile compounds. Humans, for instance, give off hundreds of volatiles, many of them chemically identified (Ellin etal., 1974). The volatiles include many classes of compound such as acids (gerbil), ketones, lactones, sulfides (golden hamster), phenolics (beaver, elephant), acetates (mouse), terpenes (elephant), butyrate esters (tamarins), among others. The human samples mentioned before contained hydrocarbons, unsaturated hydrocarbons, alcohols, acids, ketones, aldehydes, esters, nitriles, aromatics, heterocyclics, sulfur compounds, ethers, and halogenated hydrocarbons. Sulfur compounds are found in carnivores, such as foxes, coyotes, or mustelids. The major volatile compound in urine of female coyotes, Canis latrans, is methyl 3-methylhut-3-enyl sulfide, which accounts for at least 50% of all urinary volatiles (Schultz etal, 1988). 

For mammals, if not vertebrates in general, multicomponent pheromones appear to be the rule. Such mixtures can comprise compounds of a wide range of volatility. They have been variously termed odor profile, pattern, odor image (Albone, 1984), gestalt (Evans ct al., 1978), or mosaic (Johnston, 2005). One of the best-investigated odor profiles is that of the scent mark of the saddle-back tamarin, S. fuscicoUis, (Smith et al, 1985). Here, not even the 16 butyrate esters are sufficient for subspecies recognition. Additional volatiles are also required. 

The resolution of racemic FTC butyrate (34) was required for the synthesis of the antiviral drug emtricitabine (Emtriva) (Scheme 7.15) a nucleoside reverse transcriptase inhibitor targeted for treatment of human immunodeficiency virus (HIV) and hepatitis infections [35]. The racemic FTC butyrate ester (34) was treated with immobilized cholesterol esterase, which cleaved the required isomer to the corresponding alcohol (-) 35 with 91% and 52% conversion [36]. The product was isolated as the hydrochloride salt to give 31% yield (98% ) from the 8 kg demonstration. The esterase was immobilized by precipitation onto an accurel polypropylene support using acetone followed by cross linking with glutaralde-... 

Cellulose Acetate, Propionate, and Butyrate. Cellulose acetate is prepared by hydrolyzing the triester to remove some of the acetyl groups the plastic-grade resin contains 38-40% acetyl. The propionate and butyrate esters are made by substituting propionic acid and its anhydride (or butyric acid and its anhydride) for some of the acetic acid and acetic anhydride. Plastic grades of cellulose-acetate-propionate resin contain 39-47% propionyl and 2-9% acetyl cellulose-acetate-butyrate resins contain 26-39% butyryl and 12-15% acetyl. 

Moreno, Jose M. Samoza, A. del Campo, Carmen Liama, Emilio F. Sinisterra, Jose V. Organic reactions catalyzed by immobilized lipases. Part I. Hydrolysis of 2-aryl propionic and 2-aryl butyric esters with immobilized Candida cylindracea lipase. J. Mol. Catalysis A Chemical 1995, 95, 179-92. 

Propionic and butyric esters undergo the same type of condensation ... 

Other examples in which finely divided silvor is used, are, the preparation of suberic ester from y-brom-butyric ester, aud di-isopropyl succinic ester from a-brom-isovaleric ester 2... 

Butyric acid Ethyl alcohol Ethyl butyrate (Ester)... 

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