O-Aminoisobutyric acid

A-[2-(1, 3-Dioxo-1,3-dihydro-27/-isoindol-2-yl)-2-methylpropanoyl]-o -aminoisobutyric acid iV -[2-(fert-butylperoxy)-2-propyl] amide (AHAPAA) 1.447 176.0 162... 

RS- P-Aminoisobutyric acid (a-methyl-P-alanine) [10569-72-9] M 103.1, m 176-178 , 178-180 , 181-182 , R -(-)- isomer [144-90-1] m 183 , [a] -21 (c 0.43, HjO), pKes,(,) 3.7, pKEst(2) 10.2. Colorless prisms from hot H O, were powdered and dried in vacuo. The purity is checked by paper chromatography (Whatman 1) using ninhydrin spray to visualise the amino acid Rp values in 95% MeOH and n-PrOH/5N HCOOH (8 2) are 0.36 and 0.50 respectively. [Kupiecki and Coon Biochem Prep 7 20 7960 Pollack J Am Chem Soc 65 1335 7943.] The R-enantiomer, isolated from iris bulbs or human urine was crystd from H2O and sublimed in vacuo [Asen et al. J Biol Chem 234 343 7959]. The RS-hydrochloride was recrystd from EtOH/Et20 m 128-129 , 130° [Bbhme et al. Chem Ber92 1258, 1260, 1261 7959]. 

Af- 2-(Methoxycarbonyl)benzoylJ-(o -aminoisobutyryl)-a-aminoisobutyric acid A7-[2-(tert-butylperoxy)-2-propyl]amide (AHANUS) 1.436 140.2 162... 

L8. Lindan, O., Paper chromatography of Gambian urines amino-acid pattern and excretion of 3-aminoisobutyric acid. Malnutrition in African mothers, infants and young children. Rep. 2nd Inter-african (C.C.T.A.) Conf. on Nutrition, Gambia, 1952 pp. 195-196 (1954). 

L-MeLan ] MC-LR 1115 Aba Aminoisobutyric acid ADMAdda O-Acetyl-O-demethylAdda Dha Dehydroalanine Dhb Dehydrobutyrine DMAdda O-DemethylAdda E(Ome) Glutamic acid methyl ester H4Y 1,2,3,4-tetrahydrotyrosine Har Homoarginine 1000 Microcystis spp. Hil Homoisoleucine Hph Homophenylalanine Hty Homotyrosine Hty Homotyrosine MeLan A -Metiiyllantiiionine M(0) Metiiionine S-oxide MeS er A -Methylserine NR Not Reported [152]... 

An in vitro study (Kukongviriyapan et al. 1990) suggests that tetrachloroethylene can directly affect hepatocytes. Vapor exposure of rat hepatocytes to tetrachloroethylene (2-4 pL) significantly decreased the hepatocyte uptake of taurocholate, ouabain, and 2-aminoisobutyric acid, all substances that require adenosine 5 -triphosphate (ATP) for uptake. The uptake of cadmium and 3-O-methyl-D-glucose, substances that do not require ATP, was not affected. Cellular ATP was decreased by tetrachloroethylene but only at cytotoxic levels. Tetrachloroethylene also decreased membrane ATPase activity leading the investigators (Kukongviriyapan et al. 1990) to hypothesize that the effect of tetrachloroethylene on transport may result from both a decrease in ATP levels and an inhibition of cell membrane ATPases. 

Fig. 2. The elution pattern of a standard mixture of OPA-derivatized primary amines, separated on a 5 (Jim Nucleosil C-18 column (200 X 4.6 mm id). The flow-rate was 1 mL/min employing the indicated gradient of metlianol and Na phosphate buffer (50 mA4, pH 5.25). Each peak represents 39 pmol except for those indicated below. 1, glutathione 2, cysteic acid 3, O-phosphoserine (19.5 pmol) 4, cysteine sulfinic acid 5, aspartic acid 6, asparagine (19.5 pmol) 7, glutamic acid 8, histidine 9, serine 10, glutamine 11, 3-methyl-histidine 12, a-aminoadipic acid (9.8 pmol) 13, citrulline (9.8 pmol) 14, carnosine 15, threonine,glycine 16, O-phosphoethanolamine 17, taurine (19.5 pmol) 18, p-alanine (19.5 pmol) 19, tyrosine 20, alanine 21, a-aminoisobutyric acid 22, aminoisobutyric acid 23, y-amino-ii-butyric acid 24, p-amino-u-butyric acid 25, a-amino-butyric acid 26, histamine 27, cystathione (19.5 pmol) 28, methionine 29, valine 30, phenylalanine 31, isoleucine 32, leucine 33, 5-hydroxytryptamine (5-H i ) 34, lysine. The chromatographic system consisted of a Varian LC 5000 chromatograph and a Schoeffel FS 970 fluorimeter.

Aminoethanol 2-Aminoisobutyric Acid Ammonia Ammonia Solution Ammonium Ammonium Acetate Ammonium Alum Ammonium Bicarbonate Ammonium Bichromate Ammonium Bifluoride Ammonium Bromide Ammonium Carbonate Ammonium Chloride Ammonium Dichromate Ammonium Fluoride Ammonium Glycolate Ammonium Hydrogen Carbonate Ammonium Hydrogen Fluoride Ammonium Hydrosulfide Ammonium Hydroxide Ammonium Hyposulfite Ammonium Iron Sulfate Ammonium Molybdate Ammonium m-Phosphate Ammonium Nitrate Ammonium o-Phosphate Ammonium Oxalate Ammonium Peroxydisulfate Ammonium Persulfate Ammonium Phosphate Ammonium Phosphate Dibasic Ammonium Rhodanide Ammonium Sulfamate Ammonium Sulfate Ammonium Sulfide Ammonium Thiocyanate Ammonium Thioglycolate Ammonium Thiosulfate... 

Biologically active molecules containing amide bonds suffer usually of pharmacokinetic liability. In order to increase their stability, bioisosteric transformation of the carboxamide have been performed and yielded a lot of successful examples especially in the area of petidomimetic. The isosteric replacements for peptidic bonds have been summarized by Spatola and by Fauchere. " The most used and well-established modihcations are iV-methylation, configuration change (o-conhguration at Ca), formation of a retroamide or an a-azapeptide, use of aminoisobutyric or dehydroamino acids, replacement of the amidic bond by an ester [depsipeptide], ketomethylene, hydroxyethyl-ene or thioamide functional group, carba replacement of the amidic carbonyl, and use of an olefinic double bond (Figure 15.33). 

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