Alcohols naturally occurring

Ethanol (EtOH, alcohol ) naturally occurs in fruit in small quantities. Alcoholic drinks contain much higher concentrations. Their alcohol content is usually given as percent by volume. To estimate alcohol uptake and the blood alcohol level, it is useful to convert the amount to grams of ethanol (density 0.79 kg L ). For example, a bottle of beer (0.5 L at 4% v/v alcohol) contains 20 mb = 16 g of ethanol, while a bottle of wine (0.7 L at 12% v/v alcohol) contains 84 ml = 66 g ethanol. 

As a chiral alcohol, naturally occurring (-)-menthol was selected and esterified with racemic acid 3. It was surprising that the diastereomeric esters 47a and 47b formed were very easily separated by HPLC on silica gel (hexane/EtOAc =10 1) as illustrated in Fig. 9.10. The separation and resolution factors were extraordinarily high (a = 1.83, = 4.55), indicating that acid 3 has great ability to recognize... 

However, a source of the non-natural 9S isomer (2) was first required. The ready availability of natural crinitol made a racemization/resolution route, as illustrated in Scheme 1, attractive. Racemization was accomplished by Collins oxidation (16,25) to the dicarbonyl compound (14), followed by lithium aluminum hydride (LAH) reduction to give the racemic mixture (1 + 2). Resolution via diastereomeric derivatives seemed plausible. Esterification with enantiomerically pure a-methoxy-a-(trifluoromethyl) phenylacetic acid (MTPA) (17), followed by separation of diastereomers by recycle-HPLC (R-HPLC), had earlier been used to purify enantiomers of ipsenol and ipsdienol (26). A model system, the resolution of -3-nonen-2-ol, a secondary allylic alcohol naturally occurring in Rooibos tea (16,27), also worked satisfactorily. Therefore, the route using the bis-(MTPA) esters was selected for crinitol. 

Flavouring agent (No.) Most recent annual volume (kg) Intake pg/day pg/kg bw per day Intake of Annual volume in Consumption ratio alcohol naturally occurring equivalents foods (kg) (pg/kg bw per day) ... 

Pentitols C5- ugar alcohols. Naturally occurring P. are d- and L-arabitol, ribitol and xylitol. 

The fatty acids occur in nature chiefly as glycerides see fats), which constitute the most important part of the fats and oils, and as esters of other alcohols, the waxes. The naturally occurring fatty acids are mostly the normal straight-chain acids with an even number of carbon atoms. 

M.p. 283 C (decomp.). Soluble in water and alcohol. The naturally occurring substance is laevorotatory. Methionine is one of the natural sulphur-containing amino-acids, and is present in small quantities in the hydrolysis pro-... 

M.p. SS C, b.p. 2I0 C. Important fatty alcohol obtained from naturally occurring glycerides. Used in the pharmaceutical and cosmetics industries and as a gel stabilizer for greases. 

Miscellaneous Pharmaceutical Processes. Solvent extraction is used for the preparation of many products that ate either isolated from naturally occurring materials or purified during synthesis. Among these are sulfa dmgs, methaqualone [72-44-6] phenobarbital [50-06-6] antihistamines, cortisone [53-06-5] estrogens and other hormones (qv), and reserpine [50-55-5] and alkaloids (qv). Common solvents for these appHcations are chloroform, isoamyl alcohol, diethyl ether, and methylene chloride. Distribution coefficient data for dmg species are important for the design of solvent extraction procedures. These can be determined with a laboratory continuous extraction system (AKUEVE) (244). 

As solvents, the amyl alcohols are intermediate between hydrocarbon and the more water-miscible lower alcohol and ketone solvents. Eor example, they are good solvents and diluents for lacquers, hydrolytic fluids, dispersing agents in textile printing inks, industrial cleaning compounds, natural oils such as linseed and castor, synthetic resins such as alkyds, phenoHcs, urea —formaldehyde maleics, and adipates, and naturally occurring gums, such as shellac, paraffin waxes, rosin, and manila. In solvent mixtures they dissolve cellulose acetate, nitrocellulose, and ceUulosic ethers. 

Other processing aids utilized in tires are vegetable oils (fatty acids, fatty acid esters/alcohols, and metal salts of these oils), naturally occurring resins such as pine tar, hydrocarbon resins from petroleum stUlbottoms, and vulcanized vegetable oils (WOs). WOs were utilized heavily in the early 1900s, but are no longer used extensively in tires. 

Essential oils are obtained from fmits and flowers (61,62). Volatile esters of short- and medium-chain carboxyHc acids or aromatic carboxyHc acids with short- and medium-chain alcohols are primary constituents of essential oils, eg, ethyl acetate in wines, brandy, and in fmits such as pineapple ben2yl acetate in jasmine and gardenia methyl saHcylate in oils of wintergreen and sweet birch. Most of these naturally occurring esters in essential oils have pleasant odors, and either they or their synthetic counterparts are used in the confectionery, beverage, perfume, cosmetic, and soap industries (see Oils, essential). 

As many natural and synthetic /3-lactams bear 3-acylamino substituents, the corresponding free amines or protected forms thereof are versatile synthetic intermediates. They may be prepared in several ways, for example by deacylation of the 7-amido group in naturally occurring penicillins by enzymic or chemical means. Chemical degradation usually involves conversion of the amide to a chloroimidate followed by cleavage with aqueous alcohols (75S547 p. 560, 78T1731 p. 1753). 

Acids that are solids can be purified in this way, except that distillation is replaced by repeated crystallisation (preferable from at least two different solvents such as water, alcohol or aqueous alcohol, toluene, toluene/petroleum ether or acetic acid.) Water-insoluble acids can be partially purified by dissolution in N sodium hydroxide solution and precipitation with dilute mineral acid. If the acid is required to be free from sodium ions, then it is better to dissolve the acid in hot N ammonia, heat to ca 80°, adding slightly more than an equal volume of N formic acid and allowing to cool slowly for crystallisation. Any ammonia, formic acid or ammonium formate that adhere to the acid are removed when the acid is dried in a vacuum — they are volatile. The separation and purification of naturally occurring fatty acids, based on distillation, salt solubility and low temperature crystallisation, are described by K.S.Markley (Ed.), Fatty Acids, 2nd Edn, part 3, Chap. 20, Interscience, New York, 1964. 

It may also be mentioned that a number of commercial polymers are produced by chemical modification of other polymers, either natural or synthetic. Examples are cellulose acetate from the naturally occurring polymer cellulose, poly(vinyl alcohol) from polyfvinyl acetate) and chlorosulphonated polyethylene (Hypalon) from polyethylene. 

The naturally occurring fenchyl alcohol is optically inactive and melts at 33° to 35°, which agrees with the observations of Wallach, a mixture of the two optically active forms, each of which melted at 45°, melting at 33° to 35°. 

There exists in East Indian sandalwood oil an alcohol, of the formula CjHjgO, which has been named santelol, or santenone alcohol. It is closely allied to, and much resembles, the alcohol obtained by the hydration of the hydrocarbon, santene q.v.), and is probably stereo-isomeric with it. There is some difference of opinion as to the proper nomenclature of the two alcohols. According to Charabot, the naturally occurring alcohol, also obtainable by the reduction of santenone, is analogous to borneol, and should therefore be termed, if that analogy is... 

Preeclampsia, Viagra and, 164 Prelog, Vladimir, 181 Prepolymer, epoxy resins and, 673 Priestley, Joseph, 245 Primary alcohol, 600 Primary amine, 916 Primary carbon. 84 Primary hydrogen, 85 Primary structure (protein), 1038 Primer strand (DNA), 1108 pro-R prochiralitv center, 316 pro-S prochirality center, 316 Problems, how to work, 27 Procaine, structure of, 32 Prochirality, 315-317 assignment of, 315-316 naturally occurring molecules and, 316-317... 

S,3S)-(+)-Aziridine-2,3-dicarboxylic acid (234 Scheme 3.86), an example of a naturally occurring aziridinecarboxylic acid, is a metabolite of Streptomyces MD398-A1. This aziridine was prepared by treatment of diethyl (2i ,3K)-(-)-oxir-ane-2,3-dicarboxylate (231) with trimethylsilyl azide in EtOH/DMF to produced azido alcohol 232 [137], and treatment of this alcohol with triphenylphosphine afforded the aziridine dicarboxylate 233 in 71 % yield. Hydrolysis of 233 afforded the natural product 234 in 69% yield. 

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