Methyl-butanoic acid

Chemical Name 2-[ [2-[3-(Acetylamino) -2,4,6-triiodophenoxy] ethoxy] methyl] -butanoic acid... 

Valine Val V 2-Amino-3-methyl-butanoic acid (C H jfeCH - C H(N H2) - COOH... 

Valine (Val or V) ((5)-2-amino-3-methyl-butanoic acid) is a nonpolar, neutral, aliphatic amino acid with the formula HOOCCH(NH2)CH(CH3)2. Along with Leu and He, Val is a branched-chain amino acid and is found in high concentrations in the muscles. Val is needed for muscle metabolism and coordination, tissue repair, and for the maintenance of proper nitrogen balance in the body. ° The steric hindrance present in Val and He (caused by branching) lowers the rate of coupling reactions, resulting in an increase in side reactions. ... 

Another interesting example of resolution through formation of diastereo-mers is the isolation of four stereoisomers of 3-amino-2-methyl-3-trifluoro-methyl butanoic acid [55]. In this process, the chemical-enzymatic method by the combination of chemical and enzymatic reaction is a very convenient. At first, -phenylacetyl derivatives 61a and 61b were prepared in excellent isolated yields via the Schotten-Baumann procedure. After these materials were hydrolysed with penicillin acylase (EC 3.5.1.11) from Escherichia coli until attainment of 50% conversion, enzymatically unconverted -phenylacetyl derivatives 62 a and 62 b (organic layer) and amino acids 63 b and 63 d (aqueous layer) were separated. Acidic hydrolysis of unconverted materials produced other stereoisomers 63 a and 63 c in high optical pure form. 

The simple herbacic acid (938) was isolated from Dysidea herbacea from the Great Barrier Reef, and may be a precursor to more complex trichloromethyl metabolites (990). Another collection of Dysidea sp. from Australia s Great Barrier Reef yielded five new metabolites (939-943) for which the absolute stereochemistry was determined by correlation with (-)-(.S )-4,4,4-trich loro-3-methyl butanoic acid (991). Dysidea herbacea from the Great Barrier Reef contains (-)-neodyside-nin (944), which is an isomer of the well-known and often isolated dysidenin. 

To a 5 L 3-neck round bottom flask with stir bar was added the crude N-(3-amino)-propyl)valine methyl ester (150 g, 0.8 mol) and dichloromethane (3.2 L). Carbonyldiimidazole (232 g, 1.44 mol) was added slowly in portions over 25 min. The solution was allowed to stir at ambient temperature for 40 hours. Water (200 mL) was added over 1 h with stirring until no more gas evolution occurred. A solution of 35% HCI was slowly added to the stirring solution until the solution became acidic. The solution was then partitioned and was washed with water. The organic layer was dried over sodium sulfate and was concentrated to yield 126 g (74%) of 2S-(l-tetrahydro-pyrimid-2-onyl)-3-methyl butanoic acid methyl ester as a colorless solid. 

To a 12 L 3-neck round bottom flask with stir bar was added 2S-(1-tetrahydro-pyrimid-2-onyl)-3-methyl butanoic acid methyl ester (126 g, 0.588 mol), water (1.3 L), and THF (3.9 L). The solution was cooled to 0°C in an ice-water bath and lithium hydroxide monohydrate (74 g, 1.76 mol) was added in one portion with rapid stirring. The solution was allowed to stir at 0°C for 14 hours. It was then acidified to pH 11 by slow addition of 50% aq. phosphoric acid and the THF was removed in vacuo. The aqueous phase was washed with isopropyl acetate (2 L) and was subsequently acidified to pH by slow addition of 35% aq. HCI. The aqueous layer was then extracted with ethyl acetate. The combined organic layers were concentrated to give the desired product (105 g) as a white solid. The compound was then purified by... 

The solution was cooled to 0°C and filtered to give 92 g (75%) of pure 2S-(1-tetrahydro-pyrimid-2-onyl)-3-methyl butanoic acid methyl ester. 

The mixture of (2S,3S,5S)-2-(2,6-dimethylphenoxyacetyl)amino-3-hydroxy-5-amino-l,6-diphenylhexane (100 g, 0.22 mol), 2S-(l-tetrahydro-pyrimid-2-onyl)-3-methyl butanoic acid methyl ester (44.8 g, 0.22 mol) and 750 ml DMF was cooled in an ice/water bath. N-Hydroxybenzotriazole (90.9 g, 0.67 mol), l-ethyl-3-[3-dimethylaminopropyl]carbodiimide (86 g, 0.45 mol) and triethylamine (62.5 ml, 0.45 mol) were added and the ice bath was removed, allowing the reaction mixture to stir with warming to room temperature for 5 hours. The mixture was diluted with 1000 ml of IPAC and quenched with 1000 ml of water. The mixture was shaken and separated, the aq. layer was extracted IPAC, the organics were washed with 10% HCI, solution of NaHC03 with 100 ml hexanes, then washed 500 ml water, and brine, dried over MgS04, filtered and concentrated to provide. (2S,3S,5S)-2-(2,6-dimethylphenoxyacetyl)amino-3-hydroxy-5-(2S-(l-tetrahydro-pyrimid-2-onyl)-3-methylbutanoyl)amino-l,6-diphenylhexane as a white foam. 

Butanol Pentanoic acid (80 %) 2-Methyl butanoic acid (20%) 0.1... 

As already mentioned, one of the products of action of hydroxyl radicals on proteins is protein hydroperoxides (G6). Valine and lysine residues are particu-larily susceptible to hydroperoxide formation. Reduction of hydroperoxides produces respective hydroxy derivatives of amino acids. Three valine hydroxides derived from hydroperoxides of this amino acid have been characterized structurally as p-hydroxyvaline [(2S)-2-amino-3-hydroxy-3-methyl-butanoic acid], (2S,3S)-y-hydroxyvaline [(2S,3S)-2-amino-3-hydroxymethyl-butanoic acid], and (2S,3R)-y -hydroxyvaline [(2S,3R)-2-amino-3-hydroxymethyl-butanoic acid (Fig. 12). They are suggested to be possible markers of protein peroxidation (F21). 

Wine contains a mixture of straight chain fatty acids, usually referred to as short chain (C2-C4), medium chain (Ce-Cio), long chain (C12-C18), and a group of branched-chain fatty acids that include 2-methyl propanoic, 2-methyl butanoic, and 3-methyl butanoic acids. Acetic acid is quantitatively and sensorially the most important volatile fatty acid produced during alcoholic fermentation. Accounting for more that 90% of the total wine volatile acidity, acetic acid plays the most important... 

Isovaleric acid (3-methyl butanoic acid) was found to be the dominant odorant in the "high Brett" wine as detected by CharmAnalysis. The odor described by the GCO sniffer was rancid the chemical identity of the odorant was confirmed by GC-MS. This acid is produced in wine by yeast as a metabolic byproduct of protein (99). Volatile phenolic compounds, such as 4-ethyl guaiacol, guaiacol, and 4-ethyl phenol, were also among the dominate odor active compounds in this wine however, the individual contribution by each of the three phenolics was half or less than the odor activity of isovaleric acid. 

METHYL-BUTANOIC ACID 2-PHENYLETHYL ESTER see PDF775... 

C5H10O2 3-methyl butanoic acid 503-74-2 -37.00 1.1060 1 5747 C5H11N03S DL-methionine sulfoxide 454-41-1 25.00 1.1832 2... 

Iso-valeric acid is one of the isomeric five carbon acids. It is 3-methyl butanoic acid. Valine is the alphchdimmo derivative of it. a-Amino Valeric Acid, CH3—CH2—CH2—CH(NH2)—COOH... 

For the asymmetric reduction of tiglic acid (21) to 2-methyl-butanoic acid (22), isopropanol can also be used as the hydrogen source. In the presence of H4Ru4(CO)8(f ,R-DIOP)2 at 120°C, 42% of 21 was converted after 227 hr, giving R-22 (catalytic turnover 210) with 5.4% optical purity (cf. Scheme 4) 133). 

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