Acid Butyric

Ethylacetic Acid Butanoic Acid Propylformic Acid 

Critical temperature Critical denaity Diiaociation conatant at 25 C Electrical conductivity at 25 C Flaah point (ASTM open cup) Heat of combuation Heat of fuaion Heat of vaporixation Melting point 

Uniquely, milk fat of ruminants contains butyric acid, which is an important anti-cancer agent. Butyric acid is best known for its action in the colon where it is generated, along with other short-chain acids, by bacterial fermentation of dietary fiber and starch. Colonocytes utilize a portion of this butyric acid as a primary energy source, with the remainder delivered to the portal circulation and transported to the liver where it is metabolized rapidly. 

A number of animal studies have shown that dietary fibers, which liberate a constant and elevated supply of butyrate to the colon, are the most effective for prevention of chemically induced colon tumors. Moreover, the level of butyric acid in the colonic lumen of patients with colorectal cancer and adenomas was found to be lower than that in healthy individuals (Parodi, 2004). 

There are a number of studies that show synergism between butyrate and other dietary components and common drugs in reducing cancer cell growth. This could result in lower plasma butyrate requirements for anticancer action (Parodi, 2004). In summary  

portions of carbon tetrachloride. Keep the carbon tetrachloride extract (A). 

To obtain a maximum yield of the acid it is necessary to hydrolyse the by-product, isoamyl isovalerate this is most economically effected with methyl alcoholic sodium hydroxide. Place a mixture of 20 g. of sodium hydroxide pellets, 25 ml. of water and 225 ml. of methyl alcohol in a 500 ml. round-bottomed flask fitted with a reflux (double surface) condenser, warm until the sodium hydroxide dissolves, add the ester layer and reflux the mixture for a period of 15 minutes. Rearrange the flask for distillation (Fig. II, 13, 3) and distil off the methyl alcohol until the residue becomes pasty. Then add about 200 ml. of water and continue the distillation until the temperature reaches 98-100°. Pour the residue in the flask, consisting of an aqueous solution of sodium tsovalerate, into a 600 ml. beaker and add sufficient water to dissolve any solid which separates. Add slowly, with stirring, a solution of 15 ml. of concentrated sulphuric acid in 50 ml. of water, and extract the liberated acid with 25 ml. of carbon tetrachloride. Combine this extract with extract (A), dry with a little anhydrous magnesium or calcium sulphate, and distil off the carbon tetrachloride (Fig. II, 13, 4 150 ml. distilling or Claisen flask), and then distil the residue. Collect the isovaleric acid 172-176°. The yield is 56 g. 

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MCPB, 4-(4-chloro-2-methylphenoxy)-butyric acid, CiiHisClOj. A compound in itself harmless to plants, but when absorbed and translocated in the cells, CnHuClOs is converted to a powerful herbicide, and results in the death of the plant. Acts as a selective weedkiller. Other butyric acid derivatives used commercially are 2,4-Dg and 2,4,5-Tb, the butyric acid analogues of 2,4-D and 2,4,5-T. ... 

All the amino-acids of physiological importance are a-amino-acids, e.g. (in addition to the above compounds), alanine or a-amino-propionk acid, CHaCH(NH,)COOH, and leucine or a-amino-Y-dimethyl-rt-butyric acid, (CH,)aCHCH,CH(NHa)COOH, and naturally occurring samples (except glycine) are therefore optically active. 

Let us consider a specific example, viz., the extraction of a solution of 4 Og. of n-butyric acid in 100 ml. of water at 15° with 100 ml. of benzene at 15°. The partition coefficient of the acid between benzene and water may be taken as 3 (or J between water and benzene) at 15°. For a single extraction with benzene, we have ... 

Hence one extraction with 100 ml. of benzene removes 3 0 g. (or 75 per cent.) of the n-butyric acid, whilst three extractions remove 3 5 g. (or 87-5 per cent.) of the total acid. This clearly shows the greater efficiency of extraction obtainable with several extractions when the total volume of solvent is the same. Moreover, the smaller the distribution coefficient between the organic solvent and the water, the larger the number of extractions that will be necessary. 

Ethyl n-butyrate. Use a mixture of 88 g. (92 ml.) of n-butyric acid, 23 g. (29 ml.) of ethanol and 9 g. (5 ml.) of concentrated sulphuric acid. Reflux for 14 hours. Pour into excess of water, wash several times with water, followed by saturated sodium bicarbonate solution until all the acid is removed, and finally with water. Dry with anhydrous magnesium sulphate, and distU. The ethyl n-but3rrate passes over at 119 5-120-5°, Yield 40 g. An improved yield can be obtained by distilhng the reaction mixture through an efficient fractionating column until the temperature rises to 125°, and purifying the crude ester as detailed above under methyl acetate. 

The ketones are readily prepared, for example, acetophenone from benzene, acetyl chloride (or acetic anhydride) and aluminium chloride by the Friedel and Crafts reaction ethyl benzyl ketones by passing a mixture of phenylacetic acid and propionic acid over thoria at 450° and n-propyl- p-phenylethylketone by circulating a mixture of hydrocinnamic acid and n-butyric acid over thoria (for further details, see under Aromatic Ketones, Sections IV,136, IV,137 and IV,141). 

Although turnover of the catalyst is low, even unreactive cyclohexane[526] and its derivatives are oxidatively carbonylated to cyclohexanecarboxylic acid using KiS Og as a reoxidant in 565% yield based on Pd(II)[527]. Similarly, methane and propane are converted into acetic acid in 1520% yield based on Pd(II) and butyric acid in 5500% yield [528],... 

It IS hard to find a class of compounds in which the common names of its members have influenced organic nomenclature more than carboxylic acids Not only are the common names of carboxylic acids themselves abundant and widely used but the names of many other compounds are derived from them Benzene took its name from benzoic acid and propane from propionic acid not the other way around The name butane comes from butyric acid present m rancid butter The common names of most aldehydes are derived from the common names of carboxylic acids—valeraldehyde from valeric acid for exam pie Many carboxylic acids are better known by common names than by their systematic ones and the framers of the lUPAC rules have taken a liberal view toward accepting these common names as permissible alternatives to the systematic ones Table 19 1 lists both common and systematic names for a number of important carboxylic acids... 

Water Formic acid Butyric acid Water Formic acid Propionic acid Water... 

In a chromatographic analysis of low-molecular-weight acids, butyric acid elutes with a retention time of 7.63 min. The column s void time is 0.31 min. Calculate the capacity factor for butyric acid. 

In the same chromatographic analysis for low-molecular-weight acids considered in Example 12.2, the retention time for isobutyric acid is 5.98 min. What is the selectivity factor for isobutyric acid and butyric acid ... 

One of the most sensitive tests of the dependence of chemical reactivity on the size of the reacting molecules is the comparison of the rates of reaction for compounds which are members of a homologous series with different chain lengths. Studies by Flory and others on the rates of esterification and saponification of esters were the first investigations conducted to clarify the dependence of reactivity on molecular size. The rate constants for these reactions are observed to converge quite rapidly to a constant value which is independent of molecular size, after an initial dependence on molecular size for small molecules. The effect is reminiscent of the discussion on the uniqueness of end groups in connection with Example 1.1. In the esterification of carboxylic acids, for example, the rate constants are different for acetic, propionic, and butyric acids, but constant for carboxyUc acids with 4-18 carbon atoms. This observation on nonpolymeric compounds has been generalized to apply to polymerization reactions as well. The latter are subject to several complications which are not involved in the study of simple model compounds, but when these complications are properly considered, the independence of reactivity on molecular size has been repeatedly verified. 

INSULIN AND OTTiER ANTIDIABETIC AGENTS] (Vol 14) a-Keto-butyric acid [600-18-0]... 

Butane-Naphtha Catalytic Liquid-Phase Oxidation. Direct Hquid-phase oxidation ofbutane and/or naphtha [8030-30-6] was once the most favored worldwide route to acetic acid because of the low cost of these hydrocarbons. Butane [106-97-8] in the presence of metallic ions, eg, cobalt, chromium, or manganese, undergoes simple air oxidation in acetic acid solvent (48). The peroxidic intermediates are decomposed by high temperature, by mechanical agitation, and by action of the metallic catalysts, to form acetic acid and a comparatively small suite of other compounds (49). Ethyl acetate and butanone are produced, and the process can be altered to provide larger quantities of these valuable materials. Ethanol is thought to be an important intermediate (50) acetone forms through a minor pathway from isobutane present in the hydrocarbon feed. Formic acid, propionic acid, and minor quantities of butyric acid are also formed. 

The common method of naming aldehydes corresponds very closely to that of the related acids (see Carboxylic acids), in that the term aldehyde is added to the base name of the acid. For example, formaldehyde (qv) comes from formic acid, acetaldehyde (qv) from acetic acid, and butyraldehyde (qv) from butyric acid. If the compound contains more than two aldehyde groups, or is cycHc, the name is formed using carbaldehyde to indicate the functionaUty. The lUPAC system of aldehyde nomenclature drops the final e from the name of the parent acycHc hydrocarbon and adds al If two aldehyde functional groups are present, the suffix -dialis used. The prefix formjlis used with polyfunctional compounds. Examples of nomenclature types are shown in Table 1. 

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