Glycine acetylation

Some amino-acids, e.g, glycine, can also be acetylated by this method. 

Azlactones (anhydrides of a-acylamino acids) are formed by the condensation of aromatic aldehydes with acyl derivatives of glycine in the presence of acetic anhydride and anhydrous sodium acetate. Thus beiizaldehyde and acetyl-... 

Technetium-99m mertiatide (A/-[Ai-[A/-[(benzoylthio)acetyl]glycyl]glycine) is a renal imaging agent. It is excreted by the kidneys via active tubular secretion and glomerular filtration. The kit vial is reconstituted by using 740—3700 MBq (20—100 mCi) of Tc pertechnetate and boiling for 10 minutes. 

Acetic anhydride, condensation with and acetylation of glycine, 46, 1 in cyclization of c-formylphenoxy-acetic acid to coumarone, 46, 28 in cyclization of hippuric acid to 2-phenyl-5-oxazolone, 47, 101 reaction with N-nitroso-N-phenyl-glycine to yield 3-phenylsydnone, 46,96... 

Glycine, N- ((1,3-dihydro-l, 3-dioxo-2//-isomdol-2-yl)acetyl] -, ethyl ester (2641-02-3], 93... 

The development of the aminoethylglycine polyamide (peptide) backbone oligomer with pendant nucleobases linked to the glycine nitrogen via an acetyl bridge now often referred to by PNA (peptide nucleic acid Fig. 4.1), was inspired... 

All of the carbons of glycine, serine, alanine, and cysteine and two carbons of threonine form pyruvate and subsequently acetyl-CoA. 

Figure 30-10. Conversion of threonine to glycine (see Figure 30-6) and acetyl-CoA.

Threonine. Threonine is cleaved to acetaldehyde and glycine. Oxidation of acetaldehyde to acetate is followed by formation of acetyl-CoA (Figure 30-10). Catabolism of glycine is discussed above. 

This enzyme catalyzes the conversion of pyruvate to formate and acetyl CoA and is a key enzyme in the anaerobic degradation of carbohydrates in some Enterobacteriaceae. Using an enzyme selectively C-labeled with glycine, it was shown by EPR that the reaction involves production of a free radical at C-2 of glycine (Wagner et al. 1992). This was confirmed by destruction of the radical with O2, and determination of part of the structure of the small protein that contained an oxalyl residue originating from gly-734. 

Arkowitz RA, RH Abeles (1989) Identification of acetyl phosphate as the product of clostridial glycine reductase evidence for an acyl enzyme intermediate. Biochemistry 28 4639-4644. 

Diethyl ether, methyl n-propyl ether, diethylamine, N-methyl-1 -propanamine, acetone, allyl alcohol, dimethylformamide, propanamide, 2-methylpropan-amide, 2,2-dimethylpropanamide, benzamide, dichloromethane, toluene, ethyl N-acetyl-glycinate, -alaninate, -methioninate, and -aspartate, ethyl acetate, tetrahydrofuran... 

Selectivity studies with DTU indicated marked discrimination in the clathrate formation 23,45). As in other types of clathrates, the steric factor is important in differentiation between compounds of similar functionality but different shape. For example, DTU forms crystalline complexes with some alcohols (methanol, ethanol, propanol, 1-butanol) but not with others (2-butanol). It complexes the ethyl esters of N-acetyl derivatives of glycine, alanine, methionine and aspartic acid, but not of proline, serine, phenylalanine and glutamic acid. 

Laurence, P. R., and C. Thomson. 1981. A Comparison of the Results of PCILO and Ab Initio SCF Calculations for the Molecules Glycine, Cysteine and N-Acetyl-Glycine. Theoret. Chim. Acta (Berl.) 58, 121-124. 

Fig. 7.19 Illustration of the additivity of conformational geometry functions for the -ro-tation in (CH3CO)(H)N-C(CH3)(H)(CONHCH3) (ALA). During the torsional motion about the N-C(a) bond of ALA, the interactions within the system are the same as those encountered during the N-C torsion in N-ethyl acetamide (NEA), plus those encountered during the N-C(a) torsion in N-acetyl N -methyl glycine amide offset by 120° as shown (GLY), minus those encountered during the N-C torsion in N-methyl acetamide (NMA).

Klimkowski, V. J., L. Schafer, F. A. Momany, and C. Van Alsenoy. 1985. Local Geometry Maps and Conformational Transitions Between Low-Energy Conformers of N-Acetyl-N -Methyl Glycine Amide An Ab Initio Study at the 4-21G Lever with Gradient Relaxed Geometries, J. Mol. Struct. (Theochem) 124, 143-153. 

Hunter and Nelson (41 Mil) attempted the preparation of 4(5)-aminoimidazole (25 R = H) from its acetyl derivative (28 R = H, R1 = Me), which they obtained by reduction of 4(5)-nitroimidazole (27 R = H) with tin(II) chloride in acetic anhydride. The authors noted that hydrolysis of compound (28 R = H, R = Me) with aqueous acids resulted in fission of the imidazole ring and formation of acetic acid, formic acid, ammonia, and glycine. Base hydrolysis gave similar results (41 Mil), although a trace of 4(5)-aminoimidazole (25 R = H) was detected. 

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