N-Acetyl-L-tyrosine

The protease a-chymotrypsin has been used for transesterification reactions by two groups (Entries 7 and 8) [35, 36]. N-Acetyl-l-phenylalanine ethyl ester and N-acetyl-l-tyrosine ethyl ester were transformed into the corresponding propyl esters (Scheme 8.3-2). 

Standard 0.01 M N-acetyl-L-tyrosine in 1MHC1 40 mg/100 ml 1M HC1. Use only L-tyrosine (human form). Store at 4°C. 

N-Acetyl-L-tyrosine ethyl ester 7 xlO"4 1.43xl03 193 2.7x10s... 

Lehnig M (2001) N-15 Chemically induced dynamic nuclear polarization during reaction of N-acetyl-L-tyrosine with the nitrating systems nitrite/hydrogen peroxide/horseradish peroxidase and nitrite/hypochloric acid. Arch Biochem Biophys 393 245-254... 

In the first step, we showed by analytical studies that compound 28 was a donor substrate for transketolase in the presence of D-ribose-5-phosphate as acceptor substrate and that in the second step, the hydroxylated aldehyde released 29 led to the P-elimination of protected L-tyrosine. We showed that the free L-tyrosine can thus be obtained by enzymatic deprotection of N-acetyl-L-tyrosine ethyl ester using acylase and subtilisine. In this conditions, it should be possible to carry out this assay in vivo in the presence of host cells overexpressing transketolase and auxotrophic for L-tyrosin. This strategy should offer the first stereospecific selection test of transketolase mutants. The principle of this assay may be extended to other enzymes that can release aldehydes P-substituted by L-tyrosine. 

C11H12FN03 N-acetyl-2-fluoro-DL-phenylalanine 66574-84-3 25.00 1.2317 2 21998 C11H13N04 N-acetyl-L-tyrosine 537-55-3 22.50 1.1975 2... 

C-Methylated amino acids were prepared as follows N-Acetyl-L-tyrosine-amide, polylysine HBr, Gly-Leu, Ile-NH2, Ala-Ala, Phe-Gly-Gly, histidine amide, and cystine dimethylester dihydrochloride were methylated with iodomethane to serve as standards for the assignment of peak resonances in methylated proteins. 

Iborra and co-workers (Entry 8) examined the transesterification of N-acetyl-L-tyrosine ethyl ester in different ionic liquids and compared their stabilizing effect relative to that found with 1-propanol as solvent [36]. Despite the fact that the enzyme activity in the ionic liquids tested reached only 10 to 50 % of the value in 1-propanol, the increased stability resulted in higher final product concentrations. Fixed water contents were used in both studies. 

N-acetyl-L-phenylalanine ethyl ester Transesterification of N-acetyl-L-tyrosin ethyl 39... 

CAS 537-55-3 EINECS/ELINCS 208-671-3 Synonyms (S)-2-Acetamido-3-(4-hydroxyphenyl) propanoic acid N-Acetyl-L-tyrosine... 

N-Acetyl-L-tyrosine. See Acetyltyrosine N-Acetyl-d I-tyrosine, reaction prods, with methylsilanol, copper salts. See Copper acetyl tyrosinate methylsilanol Acetyl valeryl. See 2,3-Heptanedione Acetyl vanillin. See Vanillin acetate ACH-303, ACH-307, ACH-308, ACH-323, ACH-325, ACH-331. See Aluminum chlorohydrate Achillea millefolium Achillea millefolium extract. See Yarrow (Achillea millefolium) extract... 

Azuma, I., K. Kamisango, I. Saiki, Y. Tanio, S. Kobayashi, and Y. Yamamura Adjuvant activity of N-acetyl-muramyl dipeptides for the induction of delayed-type hypersensitivity to azobenzenearsonate-N-acetyl-L-tyrosine in guinea pigs. Infect. Immun. 29, 1193 (1980). 

A soln. of 2 moles of 2,4,6-tri-ferf-butylphenol in benzene stirred 2 hrs. at room temp, under Og-free Ng with an aq. soln. of K-ferricyanide and KOH, the alkaline layer removed, the organic layer washed 5 times with water, a suspension of N-acetyl-L-tyrosine in ethyl acetate added with stirring which is continued until a clear greenish yellow soln. results 4-[p-(2-acetylamino-2-carboxyethyl)phenoxy]-2,4,6-tri-ferf-butyl-2,5-cyclohexadien-l-one. Y 77%. F. e. s. T. Matsuura and A. Nishinaga, J. Org. Chem. 27, 3072 (1962). 

Stanca-Kaposta EC, farfabal P, Cocinero EJ, Hurtado P, Simons JP (2013) Carbohydrate-aromatic interactions vibrational spectroscopy and structural assignment of isolated monosaccharide complexes with p-hydroxy toluene and N-acetyl L-tyrosine Methylamide. J Phys ChemB 117 8135... 

C17H12N2O2, Cyclo-N-methyl-L-alanyl-L-alanyl, 42B, 366 C17H13NO1, Phthalylphenylalanine, 41B, 552 Cl7H17N3O5, N-Acetyl-L-tyrosine-p-nitroanilide, 42B, 367 C17H19BrN20eS, Glycyl-L-phenylalanine p-bromobenzenesulphonate, 38B, 498... 

C,3H,.N04 N-Acetyl-L-tyrosine ethyl ester N-Acety 1- L-tyrosi n-dthy I-ester- 30.002/00.262 Jl/4... 

Free and immobilized chymotrypsin were assayed using 2mM of N-acetyl-L-tyrosine ethyl ester (ATEE) in 0.05M PBS at pH 8.0. The absorbance of the solution or the supernatant at 256 nm was plotted against the enzyme weight in the reaction mixture. The initial slope of the curve was used to evaluate the activity. 

The enzymatic catalysis has converted the group d to e with enantiomer I, which acted as a good substrate. Enantiomer II is, however, a very poor substrate, so it is essentially unchanged. Such an approach has been used to separate (resolve) racemic mixtures of amino acids. For example, the N-acetyl L-tyrosine ester is available as a racemic mixture of the L-form and the D-form. If the enzyme chymotrypsin (CT) is used to catalyze the hydrolysis of this ester in two forms at pH = 8, 25 °C and 18% CH3OH solution, only the L-form is hydrolyzed to the acid (Jones and Beck, 1976) (see Figure 5.2.12). 

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