N-Acetyl-L-glutamine

A mixture of 37.6 g of N-acetyl-L-glutamine and 1.000 ml of water is heated to 40°C, and 900 ml of an isopropanol solution containing 40 g of aluminum isopropoxide isadded to the warm mixture with stirring. The stirring is continued for 10 minutes. The reaction mixture is filtered and the filtrate is concentrated under reduced pressure. Isopropanol is added to the aqueous solution and the salt precipitates in the solution. The precipitates are collected by filtration and upon drying, 48.5 g of the crystalline-like aluminum salt of N-acetyl-L-glutamine are obtained. 

Ethchlorvynol Ethinylestradiol Fluroxene Hydroquinone Mestranol Moxestrol Noreth indrone Norethynodrel 3-Acetyl-2-fluorobiphenyl Flurbiprofen N-Acetyl-L-glutamine... 

Additional information <3, 11> (<3> N-acetyl-L-glutamate and L-glutamine have no influence on activity [3] <11,13> not inhibitory adenosine-5 -tri-phospho(5 )adenosine, phosphate, phosphonoformate [14]) [3, 14]... 

D-Fructose 6-phosphate and ammonia interact to produce hexosamine when they are added to a fraction of pig-kidney protein together with catalytic amounts of A -acetyl-n-glucosamine 6-phosphate. Neither L-glutamine nor L-asparagine can replace ammonium sulfate as a nitrogen source in this system, and D-fructose 6-phosphate cannot be replaced by D-fructose, n-xylose, n-glucose, or D-ribose. The presence of N-acetyl-D-glucosamine is also essential for this reaction. 

Figure 47-SO The major metabolic pathways for the use of ammonia by the hepatocyte. Solid bars indicate the sites of primary enzyme defects in various metabolic disorders associated with hyperammonemia /) carbamyl phosphate synthetase I, (2) ornithine transcarbamylase, (3) argininosuccinate synthetase, (4) argininosuccinate lyase, (5) arginase, (6) mitochondrial ornithine transport, (7) propionyi CoA carboxylase, (fi) methylmalonyl CoA mutase, (9) L-lysine dehydrogenase, and (10) N-acetyl glutamine synthetase. Dotted lines indicate the site of pathway activation (+) or inhibition ( ). (From Flannery OB, Hsia YE, Wolf 6. Current status of /lyperommofiemjo syndromes. Hepatology 1982 2 495-506,)...

For preparing ( C-alanine)-MDP, a modified synthesis has been described using 4,6-0-anisylidene-N-acetyl-muramyl- C-L-alanyl-D-iso-glutamine (55) which can be deprotected by mild acid treatment. 

The synthesis of the a-methyl ester of N-acetyl-muramyl-L-alanyl-D-glutamic acid (21) 45) and the ot-methyl ester of N-acetylmuramyl-L-alanyl-D-glutamine (22) 47), starts with the preparation of BOC-L-Ala-D-Glu(OBzl) and Z-L-Ala-D-Gln respectively which were esterified by means of diazomethane. 

Adam, A., M. Dews, V. Souvannavong, P. Lefrancier, J. Choay, and E. Lederer Correlation of structure and adjuvant activity of N-acetyl-muramyl-L-alanyl-D-iso-glutamine (MDP), its derivatives and analogues. Anti-adjuvant and competition properties of stereoisomers. Biochem. Biophys. Res. Comm. 72, 339 (1976). 

This compound is unstable and has not been isolated in a pure state directly from naturally-occurring material. The structure determination was carried out on material produced by enzymatic oxidation of N -(4-hydroxyphenyl)-L-glutamine and was based on elementary analysis, UV-spectroscopy, IR-spectroscopy of two acetylated derivatives, and acid hydrolysis to give glutamic acid (369). 

The N-acetyl derivative of DON (N-acetyl-6-diazo-5-oxo-L-norleu-cine) has been found to cause a drastic reduction of the UDP-N-acetyl-glucosamine concentration in rat liver (Bates et al., 1966). This effect results from an irreversible inactivation of the amidotransferase which may be demonstrated in vitro on incubation of the crude or partially purified enzyme with the inhibitor (Bates and Handschumacher, 1969). The inactivation could be prevented by the addition of glutamine or UDP-N-acetylglucosamine, and the presence of both compounds afforded better protection than either alone. Evidence was obtained for the binding of... 

DCE = 1,2-dichloroethane L = leucine NANML = N acetyl-A/ -methyl-L-leucylamide NANMQ = A -acetyl-A -me thyl-L-glutamylamide Q = glutamine. 

Data are taken from [59,60]. Single letter codes for amino acids are used as Table 4 and as follows T, threonine Q, glutamine S, serine V, valine L, leucine N, asparagine. Tba and Ac are abbreviations for t-butylacetic acid and acetyl, respectively. 

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