55836-70-9

Upstream product

• 63-91-2 L-phenylalanine 
• 100-52-7 benzaldehyde 
• 63570-52-5 N-Acetyl-DL-<α-²H>phenylalanine 
• 5874-61-3 4-benzyl-2-phenyl-2-oxazolin-5-one 
• 1255087-84-3 C₁₈H₁₈⁽²⁾HNO₃ 
• 156-06-9 2-oxo-3-(phenyl)propionic acid 
• 143673-68-1 (3R,6S)-<6-2H>-6-benzyl-3-isopropyl-2,5-dimethoxy-3,6-dihydropyrazine 
• 123074-14-6 tert-butyl (2R,5R)-5-benzyl-2-(tert-butyl)-3-methyl-4-oxo-1-imidazolidinecarboxylate 
• 100-39-0 benzyl bromide 
• 3775-01-7 5-benzylidenehydantoin 
• 114-76-1 sodium phenylphyruvate 
• 123052-94-8 tert-butyl (2R,5S)-5-benzyl-2-(tert-butyl)-5-deuterio-3-methyl-4-oxo-1-imidazolidinecarboxylate 

Downstream Products

• 1005482-89-2 N-Fmoc-L-[α-2H]phenylalanine 

Relevant academic research and scientific papers

Development and Scale-Up of Stereoretentive α-Deuteration of Amines

A stereoretentive deuteration of amino acids and amines has been developed using ruthenium on carbon catalyst, hydrogen gas at atmospheric pressure, and deuterium oxide as a source of deuterium. The process was successfully scaled-up, avoiding the use of expensive and sensitive catalyst and avoiding the use of deuterium gas under pressure. High deuterium incorporation and high yield of labeled compounds were obtained by a simple filtration process.

Asymmetric synthesis of α-deuterated α-amino acids

α-Deuterated-α-amino acids represent a very special class of stable isotopically labeled compounds, used in advanced biomedical research. Herein, we disclose a generalized approach for the preparation of α-2H-α-amino acids in enantiomerically pure form and with up to 99% deuteration. The reaction chemistry involved in this process is based on the dynamic kinetic resolution of racemates or (S)-(R) interconversion via the formation of intermediate Ni(ii) complexes derived from unprotected amino acids and recyclable tridentate ligands. Operationally convenient conditions, excellent chemical yields, diastereoselectivity and the degree of the deuteration bode well for the wide application of this methodology for the preparation of tailor-made α-2H-α-amino acids.

Enantioselective synthesis of α-deuterium labelled chiral α-amino acids via dynamic kinetic resolution of racemic azlactones

Catalytic dynamic kinetic resolution (DKR) of racemic azlactones with EtOD using squaramide-based dimeric cinchona alkaloid organocatalysts is shown to be a highly effective strategy for the preparation of enantiomerically pure α-deuterated chiral α-amino

Isotope effects in oxidative deamination of L-phenylalanine

The mechanism of reversible oxidative deamination of L-phenylalanine into phenylpyruvic acid catalyzed by enzyme L-Phenylalanine Dehydrogenase (EC 1.4.1.20) using kinetic and solvent isotope effects was studied. Copyright

A stereoselective synthesis of α-deuterium-labelled (S)-α-amino acids

An atom-efficient and stereoselective synthesis has been developed for the preparation of α-2H-labelled (S)-α-amino acids, starting from a novel chiral diketopi-perazine scaffold. Efficient mono-alkylation of the chiral template afforded the (S)-substituted adducts with the nature of the electrophile significantly effecting the stereochemical outcome. Subsequent alkylation was totally selective producing the 1, 4-cis adduct as the sole diastereoisomer. The deprotection was carried out using cerium ammonium nitrate followed by acid hydrolysis affording the enantipure α-amino acids. Springer-Verlag 2010.

Synthesis of isotopically labelled L-phenylalanine and L-tyrosine

A synthetic route to stable-isotope-substituted L-phenylalanine is presented, which allows the introduction of 13C, 15N, and deuterium labels at any position or combination of positions. For labelling of the aromatic ring, a synthetic route to ethyl benzoate (or benzonitrile) has been developed, based on the electrocyclic ring-closure of a 1,6-disubstituted hexatriene system, with in situ aromatization by elimination of one (amino) substituent. Several important (highly isotopically enriched) synthons have been prepared, namely benzonitrile, benzaldehyde, ethyl benzoate, and ethyl diphenyloxyacetate. Labelled L-phenylalanines have been synthesized from both aromatic precursors by initial conversion into sodium phenylpyruvate and subsequent transformation of this intermediate into the L-α-amino acid by an enzymatic reductive amination reaction. In this manner, highly enriched phenylalanines are obtained on the 10-gram scale and with high enantiomeric purities (≥ 99% ee). The method has been validated by the synthesis of [1'13C]-L-Phe and [2-D]-L-Phe. In addition, two methods are described for the introduction of isotopes into L-tyrosine starting from the isotopically enriched precursors benzonitrile and ethyl benzoate.

Stereospecific Synthesis of α-Deuteriated α-Amino Acids: Regiospecific Deuteriation of Chiral 3-Isopropyl-2,5-dimethoxy-3,6-dihydropyrazines

Base-catalysed deuteriation of (3R)- or (3S)-3-isopropyl-2,5-dimethoxy-3,6-dihydropyrazines in refluxing CH3O2H-2H2O gives the -isotopomer in excellent yields without disturbing the stereogenic centre at C-3.These compounds provide convenient and efficient access to a range of (R)- and (S)-α-deuteriated α-amino acids, including serine, aspartic acid, allylglycine and phenylalanine, via alkylation of the butyllithium generated C-6 anion.

Regiospecific Deuteriation of Chiral 3-Isopropyl-2,5-dimethoxy-3,6-dihydropyrazines in the Stereospecific Synthesis of α-Deuteriated α-Amino Acids

Base-catalysed deuteriation of (3R)- or (3S)-3-isopropyl-2,5-dimethoxy-3,6-dihydropyrazine in refluxing CH3O(2)H-(2)H2O gives the isotopomer in excellent yield without disturbing the stereogenic centre at C-3, and thus providing convenient and e

PREPARATION OF α-DEUTERATED L-AMINO ACIDS USING E. coli B/It7-A CELLS CONTAINING TRYPTOPHANASE

A convenient method of preparation of α-deuterated L-amino acids via stereospecific isotope exchange in D2O catalyzed by lyophilized E. coli B/It7-A cells abundant in tryptophanase is reported

Synthesis of Nonproteinogenic (R)- or (S)-Amino Acids. - Analogues of Phenylalanine, Isotopically Labelled and Cyclic Amino Acids from tert-Butyl 2-(tert-Butyl)-3-methyl-4-oxo-1-imidazolidinecarboxylate (Boc-BMI)

The enantiomerically pure glycine derivatives (R)- and (S)-Boc-BMI, commercially available on a kg scale, are used as starting materials (Scheme 1) for the preparation of (i) open-chain amino acids such as α-deuterio amino acids (4,5), β-arylalanines (2), aspartic acid derivatives (6, 7a, 8), or ω-halo amino acids (7b,c, 12, 13, 16, 17, 19, 22), (ii) of α-aminocycloalkanecarboxylic acids (9, 11), and (iii) of heterocyclic α-amino acids (14, 15, 18, 20) containing azetidine, pyrrolidine, piperidine or perhydroazepine rings.Inversion by deprotonation/protonation ordeuteration allows to prepare either enantiomer of an amino acid from the same Boc-BMI enantiomer (Scheme 5).Effects of additives such as the cyclic urea DMPU, lithium salts, or secondeary amines upon the reactivity of lithium enolates are discussed and, in part, exploited.