Aspartylphenylalanine

Alternatively, oxazolones have been used as reagents to activate and to couple N-protected dicarboxylic amino acids wherein the carboxylate moiety acts as the nucleophile. For example, 2,4-dimethyl-5(4//)-oxazolone 255 reacts with N-benzyloxycarbonyl-L-aspartic acid to give a mixture of the anhydrides 256 and 257. Subsequent reaction of 256 and 257 with phenylalanine methyl ester hydrochloride and A-methylmorpholine produces a mixture of the a-isomer 258 and p-isomer 259 of Al-benzyloxycarbonyl-aspartylphenylalanine methyl ester (Scheme 7.83). °... 

APM = aspartame, DKP = diketopiperazine, AP = aspartylphenylalanine, PMe = phenylalanine methyl ester. Phe = phenylalanine, PA = phenylalanine-aspartic acid, Asp = aspartic acid. 

Aspartame and its degradation products aspartylphenylalanine, aspartic acid, and phenylalanine can also be separated after reaction with naphthalene-2,3-dicarboxaldehyde (NDA) in the presence of cyanide (sodium or potassium cyanide) in borate buffer (50 mM, pH 8). This reaction affords highly fluorescent and stable l-cyano-2-substituted-benz[/]isoindole (CBI) derivatives that can be detected at 420 nm excitation and 490 nm emission. The CBI derivatives are separated on a TSK ODS-120T column using a gradient of 30-80% B (acetonitrile water, 9 1 v/v) in A (50 mM acetate buffer, pH 6.0) (75). 

K Hayakawa, T Schilpp, K Imai, T Higuchi, OS Wong. Determination of aspartic acid, phenylalanine and aspartylphenylalanine in aspartame-containing samples using a precolumn derivatization HPLC method. J Agric Food Chem 38(5) 1256-1260, 1990. 

Influence of Sweeteners on Bitterness. In model system studies, natural fruit juice sugars were observed to raise the limonin threshold (24). An expanded study of natural and artificial sweeteners (26) demonstrated that sucrose, neohesperidin dihydro-chalcone (NHD), hesperetin dihydrochalcone glucoside (HDG) and aspartylphenylalanine methyl ester (AP) all raise the limonin threshold. At low sweetness levels HDG was the most effective followed by AP and NHD. Sucrose was without effect up to the 2% level. At sweetness levels equivalent to 1% sucrose, HDG, AP and NHD raised the limonin threshold in water from 1.0 ppm to 3.2, 2.5 and 1.3 ppm, respectively. Because of its high sweetness intensity, the concentration of NHD (16 ppm) was considerably lower than HDG (80 ppm) and AP (90 ppm). At 3-10% sucrose sweetness equivalency, the effectiveness of NHD increased substantially, sucrose moderately and HDG slightly, while that of AP decreased. Therefore, the sweeteners HDG, AP and NHD can effectively suppress limonin bitterness at low concentrations. 

Leung SS, Grant DW. Solid state stability studies of model dipeptides aspartame and aspartylphenylalanine. J Pharm Sci 1997 86(1 ) 64 71. 

The impurities found in aspartame are typically those arising from degradation. These include 3-methylenecarboxyl-6-benzyl-2,5-diketopiperazine, phenylalanylaspartic acid, a-aspartylphenylalanine, aspartic acid, phenylalanine, (Z)-p-aspartyl-(Z,)-phenylalanine methyl ester). (Z,)-P-aspartyl-(Z,)-phenylalanine methyl ester may also be formed as a byproduct when aspartame is chemically synthesized. 

Figure 1. Desorption chemical ionization (DCI) mass spectrum of aspartylphenylalanine methyl ester.

During the synthesis of a gastrin tetrapeptide Schlatter et al. 237) made the incidental but extremely interesting discovery that the dipeptide aspartylphenylalanine methyl ester 112 (aspartame) is 100-200 times as sweet as sucrose. 

CARBOXYPHENETHYL)SUCCINAMIC ACID N-iMETHYL ESTER, stereoisomer ASPARTYLPHENYLALANINE METHYL ESTER N-l-a-ASPARTYL-1-PHENYLALANINE 1-METHYL ESTER (9CI) CANDEREL DIPEPTIDE SWEETENER EQUAL METHYT-ASPARTYLPHENYLALANATE 1-METHYL N-l-a-ASPARTYL-l-PHENYLALANINE NUTRASWEET SWEET DIPEPTIDE... 

ASPARTIC ACID, COMPD. WITH 18-DECARBOXY-40-DEMETHYL-3.7-DIDEOXO-N3)-((DIMETHYLAMINO) ACETYL)-18-(((2-(DIMETHYLAMINO)ETHYL)AMINO)CARBONYL)-3,7-DIHYDROXY-N -METHYL-5-OXOCANDICIDIN D, CYCUC 15,19-HEMIACETAL (2 1) see DOS400 ASPARTYLPHENYLALANINE METHYL ESTER see ARN825... 

Aspartame. [Nutrasweet]. (3-amino-n-(a-carboxyphenethyl)succinamic acid n-methyl ester, stereoisomer aspartylphenylalanine methyl ester n-l-a-aspartyl-l-phenylalanine 1-methyl ester canderel dipeptide sweetener Equal (TM) methyl aspartylphenylalanate 1-methyl n-l-a-as-partyl-l-phenylalanine Nutrasweet (TM) sweet dipeptide). C14H18N205. 

In fact, the very name of glycine comes from the greek word for sweet (yXoKocr). Figure 1 shows the molecular models of glycine and of I -tryptophan, the sweetest of R amino acids. In addition to simple amino acids, there are several sweet peptides most of them, although composed of natural amino acidic residues, are not natural and are related to aspartame, 1-aspartylphenylalanine methyl ester, the first sweet dipeptide, discovered... 

Amino-N-(a-methoxycarbonylphenethyl) succinamic acid 3-Amino-N-(a-carboxyphenethyl)succinamic acid N-methyl ester APM Asp-phe-ome Aspartam Aspartame Aspartame, L,L-a- Aspartamo Aspartamum Aspartylphenylalanine methyl ester L-Aspartyl-L-phenylalanine methyl ester Canderel CCRiS 5456 DIpeptide sweetener EINECS 245-261-3 Equal HSDB 3915 Methyl aspartylphenylalanate Methyl L-aspartyl-L-phenylalanine Methyl L-a-aspartyl-L-phenylalanate Methyl N-L-a-aspartyl-L-phenylalaninate 1-Methyl N-L-a-aspartyl-L-phenylalanate Nutrasweet L-Phenylalanine, L-a-aspartyl-, 2-methyl ester L-Phenylalanine, N-L-a-aspartyl-, 1-methyl ester SC 18862 Succinamic acid, 3-amino-N-(a-carboxyphenethyl)-, N-methyl ester, Sweet dipeptide Tri-sweet, A sweetening agent Crystals mp = 246-247° [a]8 = -2,3° (IN HCI). Searte 6.D. Co. 

Leung S S, Grant D J W (1997). Solid state stability studies of model dipeptides Aspartame and aspartylphenylalanine./. Pharm. Sci. 86 64-71. 

Aspartame, a dipeptide ester (aspartylphenylalanine methyl ester), is hydrolyzed to L-as-partate and L-phenylalanine. High levels of phenylalanine are harmful in phenylketonurics. 

Cyclamate and saccharin are rapidly excreted in the urine, mainly unchanged. Aspartame, a monomethyl ester of aspartylphenylalanine, is degraded by digestive enzymes into its constituent amino acids. Phenyl-ketonurics should limit their intake of aspartame due to its conversion to phenylalanine in the intestine. 

NUTRASWEET ASPARTYLPHENYLALANINE METHYL ESTER SWEET DIPEPTIDE... 

Figure 32 shows a control cationic analysis of a selected batch of artificial sweetener Aspartam (L-aspartylphenylalanine methyl ester hydrochloride). In one analysis both the main component and the admixtures from the technological... 

Convert the alcohol to a tosylate and displace with excess ammonia 24.42. aspartylphenylalanine methyl ester. 24.43. Phe-Ala-GIy-Met-Ala. 24.46. (a) C-terminal amide (CONH2), or amide (Gin) of Glu (b) The N-terminal Glu is a cyclic amide (a pyroglutamyl" group) that effectively blocks the N-terminus. The C-terminal Pro is an amide (c) cyclic pentapeptide. 24.49. Ornithine is H2N(CH2)3CH(NH2)C00H, a homolog of lysine, with a similar lEP. 24.51. Ala-Lys-Phe-Glu-Gly-Tyr-Arg-Ser-Leu-Ile. 

Synonyms 3-Amino-N-(a-carboxyphenethyl) succinamic acid N-methyl ester APM Aspartylphenylalanine methyl ester N-l-a-Aspartyl-l-phenylalanine l-methyl ester Methyl aspartylphenylalanate 1 -Methyl N-L-a-aspartyl-L-phenylalanine Classification Dipeptide Definition Consists of L-aspartic acid and the methyl ester of L-phenylalanine artificial sweetener... 

Aspartic acid, potassium salt L-Aspartic acid, potassium salt. See Potassium aspartate Aspartic acid sodium salt L-Aspartic acid sodium salt L-Aspartic acid sodium salt monohydrate. See Sodium aspartate Aspartic acid, zinc salt. See Zinc aspartate Aspartylphenylalanine methyl ester N-l-a-Aspartyl-l-phenylalanine l-methyl ester. See Aspartame... 

The annual world production of L-aspartate is estimated to be 7,0001. L-Aspartate is used as an enteral and parenteral nutrient, a food additive, and a starting material for the low-calorie sweetener aspartame (aspartylphenylalanine methyl ester). It is also used as a raw material to synthesize detergent and for chelating or water treatment agents. 

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