Acetyl-DL-tryptophan

Use Nutrition and research, medicine, dietary supplement, cereal enrichment. Available commercially in all three forms, as well as acetyl-DL-tryptophan. 

L-Tryptophan is the only substance converted to kynurenine by the liver enzyme system. Such closely related compounds as n-tryptophan and acetyl-DL-tryptophan are not attacked. The reaction proceeds with the uptake of 1 molecule of O2 and causes the liberation of 1 mole of formic acid and 1 of kynurenine but no CO2. 

C HuNA N-Acetyl-DL-tryptophan methyl N-Acetyl-DL-tryptophan-methyl- 42.000/40.962 Jl/1... 

Acetyl thiophene - 657 Acetyl dl tryptophan - 251 Acetyl dl valine - 251 Acetylene tetrabromide (see Tetrabromo-ethane)... 

C HpNsO, 133186-23-9) see Aciclovir iV-acetyl-S-benzyloxy-DL-tryptophan (C2, H2,N204 53017-51-9) see Oxitriptan iV-aeetyl-lV,0-bis(trimethylsilyl)cytosine... 

Die Prafixe werden in alien Derivaten vor den Nainen der Aminosaure gesetzt (z. B. Acetyl-L-tryptophan, 4-Oxy-L-prolin, Glycyl-DL-leucin, jedoch nicht Phenyl-L-alanin, sondern nach wie vor L-Phenylalanin). 

When a solution of DL-tryptophan was treated with acetyl chloride at room temperature, a yellow substance was isolated as main product and identified as 1-methyl-3,4-dihydro-(3-carboIine-3-carboxylic acid. Under similar conditions D- or L-tryptophan reacted analogously yielding the corresponding optically active p-carbolines. Minor products, corresponding to (179) and (181) were also isolated. The formation of the three compounds (179), (180) and (181) can be viewed as an acylation of a reactive ring and the general order of positional reactivity of the indole moiety can be deduced as 2 < 1 < 5. 

Recently, the structure of the first N- and C-protected tryptophan derivative, i.e., N-acetyl-L-tryptophan methyl ester, was solved by Cotrait and Barrans (97). There is one hydrogen bond NH. .. O = C of 2.86 A between the NH indole group and the acetyl C = O of different molecules. Molecular packing in the crystal is established by van der Waals forces between the two hydrophobic methyl groups and the aromatic ring. The conformation of the tryptophanyl side chain is very close to that of the L form of DL-tryptophan formate. Fig. 5 shows bond lengths and angles of N-acetyl-L-tryptophan methyl ester. 

Phenylalanine hydroxylase occurs only in mammalian liver (that is, in the rat, guinea-pig, rabbit, d<, chicken, and human) (see also 259). No activity has been observed in (rat) lung, kidney, brain, or muscle. The system is quite speciOc for L-phenylalanine. Tjrro-sine is not formed from n-phenylalanine, nor are the corresponding p-phenols formed from N-acetyl- or N-chloroacetyl-L-phenylalanine, L-phenylalanine ethyl ester, DL-phenylglycine, phenylserine, phenylpyruvic acid, phenylethylamine, benzoic acid, hippuric acid, cinnamic acid, or mandelic acid (768), or from aniline, acetanilide, tryptophan, kynurenine, anthranilic acid, or phenylacetate (557). This specificity is a distinguishing character of the enzyme, which occurs in the same tissue as the nonspecific aromatic hydroxylase described above. 

---