63-91-2

Basic information

• Product Name: L-Phenylalanine
• Synonyms: L(-)-PHENYLALANINE;L-PHENYLALANINE;L-PHE;BETA-PHENYLALANINE;DL-2-AMINO-3-PHENYLPROPANOIC ACID;L-ALPHA-AMINO-BETA-PHENYLPROPIONIC ACID;L-BETA-PHENYLALANINE;L-2-AMINO-3-PHENYLPROPANOIC ACID
• CAS NO: 63-91-2
• Molecular Formula: C₉H₁₁NO₂
• Molecular Weight: 165.19
• EINECS: 200-568-1
• Product Categories: Food and Feed Additive;Amino ACIDS SERIES;API intermediates;Phenylalanine [Phe, F];Amino Acids and Derivatives;Amino Acids 13C, 2H, 15N;alpha-Amino Acids;Amino Acids;Biochemistry;Nutritional Supplements;L-Amino Acids;Amino Acids;Amino Acids & Derivatives;amino
• Mol File: 63-91-2.mol

Chemical Properties

• Melting Point: 270-275 °C (dec.)(lit.)
• Boiling Point: 293.03°C (rough estimate)
• Flash Point: 139.8 °C
• Appearance: White to off-white/powder
• Density: 1.29
• Vapor Pressure: 7.09E-05mmHg at 25°C
• Refractive Index: -34 ° (C=2, H2O)
• Storage Temp.: Store at RT.
• Solubility: H2O: 0.1 M at 20 °C, clear, colorless
• PKA: 2.2(at 25℃)
• Water Solubility: 1-5 g/100 mL at 25 ºC
• Stability: Stable. Incompatible with strong oxidizing agents.
• Merck: 14,7271
• BRN: 1910408
• CAS DataBase Reference: L-Phenylalanine(CAS DataBase Reference)
• NIST Chemistry Reference: L-Phenylalanine(63-91-2)
• EPA Substance Registry System: L-Phenylalanine(63-91-2)

Safety Data

• Hazard Codes: C
• Statements: 36/37/38-34
• Safety Statements: 22-24/25-37/39-45-36/37/39-27-26
• WGK Germany: 3
• RTECS: AY7535000
• F: 10
• TSCA: Yes
• Hazardous Substances Data: 63-91-2(Hazardous Substances Data)

Usage

Uses

1. Hair Care Industry:
L-Phenylalanine is used as a conditioning agent, with greater application in hair care than in skin care preparations. It helps improve the overall health and appearance of hair.
2. Suntan Products:
L-Phenylalanine is also used in suntan products, where it may enhance the effect of UVA radiation for people with vitiligo, potentially leading to darkening or repigmentation of white patches, particularly on the face.
3. Medical, Feed, and Nutritional Applications:
L-Phenylalanine is produced for various applications, including the preparation of Aspartame, a low-calorie artificial sweetener. It is also used as a nutritional supplement for its reputed analgesic and antidepressant effects.
4. Pharmaceutical Industry:
L-Phenylalanine is suggested as an intermediate for anti-cancer drugs, and a few small studies have shown promise in using it to manage alcohol withdrawal and ease PMS symptoms.
5. Food and Drink Industry:
L-Phenylalanine is used in the manufacture of food and drink products, as it affects neurotransmitters that help reduce hunger, improve memory, lessen the symptoms of ADHD and Parkinson's disease, and ease chronic pain.
6. Cocoa Substitute Industry:
According to FEMA, L-Phenylalanine is used in the cocoa substitute industry, where its chemical properties contribute to the overall flavor and quality of the product.

References

[1] http://www.umm.edu/health/medical/altmed/supplement/phenylalanine [2] Xueqin Song , Philip L. Lorenzi , Christopher P. Landowski , Balvinder S. Vig , John M. Hilfinger , Gordon L. Amidon (2005) Amino Acid Ester Prodrugs of the Anticancer Agent Gemcitabine:? Synthesis, Bioconversion, Metabolic Bioevasion, and hPEPT1-Mediated Transport, 2, 157-167.

Preparation

From PTS-negative Escherichia coli bioengineered strains.

Synthesis Reference(s)

Canadian Journal of Chemistry, 29, p. 427, 1951 DOI: 10.1139/v51-051The Journal of Organic Chemistry, 30, p. 3414, 1965 DOI: 10.1021/jo01021a035Tetrahedron Letters, 26, p. 2449, 1985 DOI: 10.1016/S0040-4039(00)94850-0

Air & Water Reactions

Water soluble. Aqueous solutions are weak acids.

Reactivity Profile

L-Phenylalanine may be light sensitive. Act as weak acids in solution.

Health Hazard

ACUTE/CHRONIC HAZARDS: When heated to decomposition L-Phenylalanine emits toxic fumes of nitrogen oxides.

Fire Hazard

Flash point data for L-Phenylalanine are not available; however, L-Phenylalanine is probably combustible.

Biochem/physiol Actions

L-Phenylalanine is an essential amino acid. It is significantly involved in the synthesis of neurotransmitters such as dopamine, epinephrine, norepinephrine, l-DOPA (Dihydroxyphenylalanine), melanin and thyroxine. L-Phenylalanine metabolism also results in phenylethylamine, that brings about effect of a stimulant in the brain and enhances mood.

Purification Methods

Likely impurities are leucine, valine, methionine and tyrosine. Crystallise L-phenylalanine from water by adding 4volumes of EtOH. Dry it in vacuo over P2O5. Also crystallise it from saturated refluxing aqueous solutions at neutral pH, or 1:1 (v/v) EtOH/water solution, or conc HCl. It sublimes at 176-184o/0.3mm with 98.7% recovery and unracemised [Gross & Gradsky J Am Chem Soc 77 1678 1955]. [Greenstein & Winitz The Chemistry of the Amino Acids J. Wiley, Vol 3 pp 2156-2175 1961, Beilstein 14 IV 1552.]

InChI:InChI:1S/C9H11NO2/c10-8(9(11)12)6-7-4-2-1-3-5-7/h1-5,8H,6,10H2,(H,11,12)

Synthetic route

methyl (2S)-2-amino-3-phenylpropanoate (2577-90-4) → L-phenylalanine (63-91-2)

Conditions	Yield
With ammonium bicarbonate; water In dichloromethane for 48h; α-chymotrypsin;	100%
With sodium hydroxide In water; ethyl acetate pH=9 - 10;	93%
at 25℃; for 0.833333h; enzyme alcalase from Bacillus licheniforms; pH 8.2;

N-Cbz-L-Phe (1161-13-3) → L-phenylalanine (63-91-2)

Conditions	Yield
With cell extract of Sphingomonas paucimobilis SC 16113 In water at 42℃; for 20h; Enzymatic reaction;	100%
With hydrogen In ethanol for 0.5h;	100%
With palladium on activated charcoal In methanol; ethyl acetate	99%

H-Phe-OEt (3081-24-1) → L-phenylalanine (63-91-2)

Conditions	Yield
With ammonium bicarbonate; water In dichloromethane for 36h; α-chymotrypsin;	100%
With Tris buffer; water at 50℃; Rate constant;
With human valacyclovirase; water at 37℃; pH=7.4; Kinetics; Time; HEPES buffer; Enzymatic reaction;

((prop-2-yn-1-yloxy)carbonyl)-L-phenylalanine (439912-45-5) → L-phenylalanine (63-91-2)

Conditions	Yield
With resin bound tetrathiomolybdate In methanol at 28℃; for 1.5h; ultrasonic bath;	100%

2-oxo-3-(phenyl)propionic acid (156-06-9) → L-phenylalanine (63-91-2)

Conditions	Yield
With formate dehydrogenase; NAD; ammonium formate at 30℃; for 24h; PheDH;	99%
With A-(modified B6)-B-<ω-amino(ethylamino)>-β-cyclodextrin In water at 30℃; for 5h; pH 8.0 (phosphate buffer); Yield given;
With formate dehydrogenase; NAD; ammonium formate at 30℃; for 24h; Mechanism; buffer (pH 8.5); other oxo-acids; PheDH;

phenylalanine amide hydrochloride (108321-83-1) → L-phenylalanine (63-91-2)

Conditions	Yield
With pyridoxal 5'-phosphate monohydrate; cobalt(II) chloride In aq. buffer at 40℃; for 4h; pH=7.0; Enzymatic reaction;	99%

(S)-2-acetylamino-3-phenylpropanoic acid (2018-61-3) → L-phenylalanine (63-91-2)

Conditions	Yield
With pepsin immobilized on terephthalaldehyde functionalized chitosan magnetic nanoparticle In acetonitrile at 20℃; for 48h; pH=2;	98%
With hydrogenchloride
With hydrogen bromide

phenylpyruvate- (620-76-8) → L-phenylalanine (63-91-2)

Conditions	Yield
With ammonium formate; tris hydrochloride; nicotinamide adenine dinucleotide; formate dehydrogenase; phenylalanine dehydrogenase In water at 30℃; for 24h;	98%
With ammonium formate; tris hydrochloride; nicotinamide adenine dinucleotide; phenylalanine and formate dehydrogenase In water at 30℃; for 24h; Equilibrium constant; pH = 8.5;	98%
With L-glutamic acid; pyridoxal 5'-phosphate In water at 40℃; for 12h; E.coli Aspartate transaminase, pH 8;	84%
With L-glutamic acid; E.coli Aspartate transaminase; pyridoxal 5'-phosphate at 40℃; for 12h; enzyme kinetics; pH 8; Miachaelis constant (Km); maximum velocity constant (vmax); further α-keto acids;	84%
With L-glutamine; human glutamine transaminase K at 37℃; pH=7.4; aq. phosphate buffer; Enzymatic reaction;

((S)-1-Cyano-2-phenyl-ethyl)-carbamic acid methyl ester (631921-67-0) → L-phenylalanine (63-91-2)

Conditions	Yield
With hydrogenchloride In water for 7h; Heating;	98%

(S)-2-hydrazinyl-3-phenylpropanoic acid (1202-31-9) → L-phenylalanine (63-91-2)

Conditions	Yield
With hydrogen; nickel In water; acetic acid under 25857.4 Torr;	97%

(S)-2-{1-[4-Nitro-1,3-dioxo-indan-(2E)-ylidene]-ethylamino}-3-phenyl-propionic acid → L-phenylalanine (63-91-2) + 2-[1-Hydrazino-eth-(E)-ylidene]-4-nitro-indan-1,3-dione

Conditions	Yield
With hydrazine hydrate In ethanol for 3h; Ambient temperature;	A n/a B 97%

Phenylalanine (150-30-1) → L-phenylalanine (63-91-2)

Conditions	Yield
With D-amino acid oxidase; E. coli branched-chain amino acid aminotransferase In water at 37℃; for 72h; Tris buffer, pH 8.5, 1mM EDTA, monosodium glutamate, bovine serum albumin, catalase, pyridoxal 5'-phosphate;	96%
With porcine kidney D-amino acid oxidase (EC 1.4.3.3.); sodium cyanoborohydride; flavin adenine dinucleotide In phosphate buffer at 37℃;	82%
With sodium hydroxide; oxygen at 30℃; for 24h; pH=7.3; aq. buffer; Enzymatic reaction; optical yield given as %ee; enantioselective reaction;	44%

N-allyloxycarbonyl-(S)-phenylalanate (90508-20-6) → L-phenylalanine (63-91-2)

Conditions	Yield
With tri-n-butyl-tin hydride; bis-triphenylphosphine-palladium(II) chloride In dichloromethane Ambient temperature;	95%

N-tert-butoxycarbonyl-L-phenylalanine (13734-34-4) → L-phenylalanine (63-91-2)

Conditions	Yield
With tetradecyl(trihexyl)phosphonium bistriflamide; trifluoroacetic acid at 130℃; for 0.166667h; Ionic liquid;	95%
With methanol; tetrachloromethane at 20℃; for 12h; UV-irradiation;	91%
With trifluoroacetic acid
With ethylenediaminetetraacetic acid; phenylmethylsulphonyl fluoride; water In aq. phosphate buffer at 30℃; Kinetics; Reagent/catalyst; Microbiological reaction; Enzymatic reaction;
With trifluoroacetic acid at 20℃; for 0.25h;

benzyl bromide (100-39-0) → L-phenylalanine (63-91-2)

Conditions	Yield
	95%
Multi-step reaction with 2 steps 1: 1.) LDA / 1.) THF, hexane, from -78 deg C to -20 deg C; 2.) THF, from -78 deg C to -20 deg C, 24 h 2: 92 percent / 1 N aq. HCl / 4 h / Heating View Scheme
Multi-step reaction with 3 steps 1: 1.) sodium bis(trimethylsilyl)amide / 1.) THF, -82 deg C, 40 min, 2.) THF, -82 deg C, 1.5 h 2: 80 percent / trifluoroacetic acid / CH2Cl2 / 4 h 3: 76 percent / H2 / PdCl2 / tetrahydrofuran; ethanol / 29 h / 2172.02 Torr View Scheme
Multi-step reaction with 2 steps 1: 1.) LDA / 1.) THF, -78 deg C, 2.) THF, -78 deg C 2: 85 percent / 6N HCl / 6 h / Heating View Scheme
Multi-step reaction with 2 steps 1: 77 percent / NaN(Si(CH3)3)2 / tetrahydrofuran / 0.67 h / -100 °C 2: 1) TFA; 2) H2 / 2) Pd / 1) CH2Cl2 View Scheme

N-Fmoc L-Phe (35661-40-6) → L-phenylalanine (63-91-2)

Conditions	Yield
With sodium azide In N,N-dimethyl-formamide at 50℃; for 1h; Temperature; Time; Solvent;	95%
Stage #1: N-Fmoc L-Phe With N-ethyl-N,N-diisopropylamine In dichloromethane for 1h; 2-chlorotrityl chloride resin; Stage #2: With piperidine In N,N-dimethyl-formamide for 0.166667h; 2-chlorotrityl chloride resin; Stage #3: With trifluoroacetic acid In dichloromethane for 0.166667h;
With piperidine In N,N-dimethyl-formamide for 0.0333333h; Solvent;

C34H29Cl2N3NiO3 → L-phenylalanine (63-91-2) + (S)-1-benzyl-N-[4-chloro-2-(2-chlorobenzoyl)phenyl]pyrrolidine-2-carboxamide (1616841-99-6)

Conditions	Yield
Stage #1: C34H29Cl2N3NiO3 With hydrogenchloride In 1,4-dioxane; methanol; water at 60℃; Stage #2: In 1,4-dioxane; methanol; water enantioselective reaction;	A 72% B 95%

D-Phenylalaninamide (5241-58-7, 5241-59-8, 17193-31-6, 60058-39-1) + butan-1-ol (71-36-3) → L-phenylalanine (63-91-2)

Conditions	Yield
	94%

(3S,6S,8S,8aS)-3-benzyl-7,7,8a-trimethyl-3,5,6,7,8,8a-hexahydro-2H-6,8-methanobenzo[b][1,4]oxazin-2-one (141895-40-1) → L-phenylalanine (63-91-2)

Conditions	Yield
With hydrogenchloride In tetrahydrofuran at 70℃; for 3h;	93%

(S)-4'-benzyl-9λ4-boraspiro[bicyclo[3.3.1]nonane-9,2'-[1,3,2]oxazaborolidin]-5'-one → L-phenylalanine (63-91-2)

Conditions	Yield
With tetrabutyl ammonium fluoride In tetrahydrofuran; water at 20℃; for 1h; Reagent/catalyst; Temperature; Solvent;	93%
With peracetic acid; disodium hydrogenphosphate In dichloromethane at 20℃; Reagent/catalyst;

Upstream product

• 4289-95-6 N-formyl-phenylalanine 
• 2018-61-3 (S)-2-acetylamino-3-phenylpropanoic acid 
• 29618-30-2 (S)-N-benzoyl-phenylalanine anilide 
• 7765-11-9 N-chloroacetyl-DL-phenylalanine 
• 2566-22-5 DL-N-benzoylphenylalanine 
• 127984-21-8 D-mandelic acid-L-phenylalanine 
• 108321-83-1 phenylalanine amide hydrochloride 
• 93379-76-1 L-phenylalanine hydrazide; dihydrochloride 
• 40099-50-1 N-p-biphenylisopropoxycarbonyl-phenylalanine (Bpoc-Phe-OH) 
• 2280-44-6 D-Glucose 
• 111-26-2 hexan-1-amine 
• 92782-35-9 (S)-2-(3,5-Dinitro-4-oxo-4H-pyridin-1-yl)-3-phenyl-propionic acid 
• 150-30-1 Phenylalanine 
• 82704-14-1 (S)-2-{(N-benzyl-2-pyrrolidinyl)carbonylamino}benzaldehyde 

Downstream Products

• 100610-68-2 (S)-2-(1,1-dioxo-1λ⁶-thiomorpholino)-3-phenyl-propionic acid 
• 17274-89-4 (S)-2-(nicotinamido)-3-phenylpropanoic acid 
• 7524-50-7 methyl (2S)-2-amino-3-phenylpropanoate hydrochloride 
• 14825-82-2 L-phenylalanine-N-carboxyanhydride 
• 96789-63-8 N-(o-carboxybenzoyl)-L-phenylalanine 
• 5123-55-7 Nα-phthaloyl-L-phenylalanine 
• 2566-30-5 N-Methyl-L-phenylalanine 
• 17469-89-5 (2S)-2-(dimethylamino)-3-phenylpropanoic acid 
• 38969-81-2 N-dichloroacetyl-L-phenylalanine 
• 31105-03-0 N-(1-deoxy-D-fructos-1-yl)-L-phenylalanine monohydrate 
• 112072-85-2 N-D-glucose-2-yl-L-phenylalanine 
• 13734-34-4 N-tert-butoxycarbonyl-L-phenylalanine 
• 78087-68-0 N-(α-acetylamino-cinnamoyl)-L-phenylalanine 
• 3081-24-1 H-Phe-OEt 

Relevant articles and documents

Recreating the natural evolutionary trend in key microdomains provides an effective strategy for engineering of a thermomicrobial N-demethylase

N-demethylases have been reported to remove the methyl groups on primary or secondary amines, which could further affect the properties and functions of biomacromolecules or chemical compounds; however, the substrate scope and the robustness of N-demethylases have not been systematically investigated. Here we report the recreation of natural evolution in key microdomains of the Thermomicrobium roseum sarcosine oxidase (TrSOX), an N-demethylase with marked stability (melting temperature over 100 C) and enantioselectivity, for enhanced substrate scope and catalytic efficiency on -C-N-bonds. We obtained the structure of TrSOX by crystallization and X-ray diffraction (XRD) for the initial framework. The natural evolution in the nonconserved residues of key microdomains—including the catalytic loop, coenzyme pocket, substrate pocket, and entrance site—was then identified using ancestral sequence reconstruction (ASR), and the substitutions that accrued during natural evolution were recreated by site-directed mutagenesis. The single and double substitution variants catalyzed the N-demethylation of N-methyl-L-amino acids up to 1800- and 6000-fold faster than the wild type, respectively. Additionally, these single substitution variants catalyzed the terminal N-demethylation of non-amino-acid compounds and the oxidation of the main chain -C-N- bond to a -C=N- bond in the nitrogen-containing heterocycle. Notably, these variants retained the enantioselectivity and stability of the initial framework. We conclude that the variants of TrSOX are of great potential use in N-methyl enantiomer resolution, main-chain Schiff base synthesis, and alkaloid modification or degradation.

Enhanced carboxypeptidase efficacies and differentiation of peptide epimers

Carboxypeptidases enzymatically cleave the peptide bond of C-terminal amino acids. In humans, it is involved in enzymatic synthesis and maturation of proteins and peptides. Carboxypeptidases A and Y have difficulty hydrolyzing the peptide bond of dipeptides and some other amino acid sequences. Early investigations into different N-blocking groups concluded that larger moieties increased substrate susceptibility to peptide bond hydrolysis with carboxypeptidases. This study conclusively demonstrates that 6-aminoquinoline-N-hydroxysuccimidyl carbamate (AQC) as an N-blocking group greatly enhances substrate hydrolysis with carboxypeptidase. AQC addition to the N-terminus of amino acids and peptides also improves chromatographic peak shapes and sensitivities via mass spectrometry detection. These enzymes have been used for amino acid sequence determination prior to the advent of modern proteomics. However, most modern proteomic methods assume that all peptides are comprised of L-amino acids and therefore cannot distinguish L-from D-amino acids within the peptide sequence. The majority of existing methods that allow for chiral differentiation either require synthetic standards or incur racemization in the process. This study highlights the resistance of D-amino acids within peptides to enzymatic hydrolysis by Carboxypeptidase Y. This stereoselectivity may be advantageous when screening for low abundance peptide stereoisomers.

A novel phenylalanine ammonia-lyase from Pseudozyma antarctica for stereoselective biotransformations of unnatural amino acids

A novel phenylalanine ammonia-lyase of the psychrophilic yeast Pseudozyma antarctica (PzaPAL) was identified by screening microbial genomes against known PAL sequences. PzaPAL has a significantly different substrate binding pocket with an extended loop (26 aa long) connected to the aromatic ring binding region of the active site as compared to the known PALs from eukaryotes. The general properties of recombinant PzaPAL expressed in E. coli were characterized including kinetic features of this novel PAL with L-phenylalanine (S)-1a and further racemic substituted phenylalanines rac-1b-g,k. In most cases, PzaPAL revealed significantly higher turnover numbers than the PAL from Petroselinum crispum (PcPAL). Finally, the biocatalytic performance of PzaPAL and PcPAL was compared in the kinetic resolutions of racemic phenylalanine derivatives (rac-1a-s) by enzymatic ammonia elimination and also in the enantiotope selective ammonia addition reactions to cinnamic acid derivatives (2a-s). The enantiotope selectivity of PzaPAL with o-, m-, p-fluoro-, o-, p-chloro- and o-, m-bromo-substituted cinnamic acids proved to be higher than that of PcPAL.

Highly Stable Zr(IV)-Based Metal-Organic Frameworks for Chiral Separation in Reversed-Phase Liquid Chromatography

Separation of racemic mixtures is of great importance and interest in chemistry and pharmacology. Porous materials including metal-organic frameworks (MOFs) have been widely explored as chiral stationary phases (CSPs) in chiral resolution. However, it remains a challenge to develop new CSPs for reversed-phase high-performance liquid chromatography (RP-HPLC), which is the most popular chromatographic mode and accounts for over 90% of all separations. Here we demonstrated for the first time that highly stable Zr-based MOFs can be efficient CSPs for RP-HPLC. By elaborately designing and synthesizing three tetracarboxylate ligands of enantiopure 1,1′-biphenyl-20-crown-6, we prepared three chiral porous Zr(IV)-MOFs with the framework formula [Zr6O4(OH)8(H2O)4(L)2]. They share the same flu topological structure but channels of different sizes and display excellent tolerance to water, acid, and base. Chiral crown ether moieties are periodically aligned within the framework channels, allowing for stereoselective recognition of guest molecules via supramolecular interactions. Under acidic aqueous eluent conditions, the Zr-MOF-packed HPLC columns provide high resolution, selectivity, and durability for the separation of a variety of model racemates, including unprotected and protected amino acids and N-containing drugs, which are comparable to or even superior to several commercial chiral columns for HPLC separation. DFT calculations suggest that the Zr-MOF provides a confined microenvironment for chiral crown ethers that dictates the separation selectivity.

Investigation of Taniaphos as a chiral selector in chiral extraction of amino acid enantiomers

Finding chiral selector with high stereoselectivity to a variety of amino acid enantiomers remains a challenge and warrants further research. In this work, Taniaphos, a chiral ligand with rotatable spatial configuration, was employed as a chiral extractant to enantioseparate various amino acid enantiomers. Phenylalanine (Phe), homophenylalanine (Hphe), 4-nitrophenylalanine (Nphe), and 3-chloro-phenylglycine (Cpheg) were used as substrates to evaluate the extraction efficiency. The results revealed that Taniaphos-Cu exhibited good abilities to enantioseparate Phe, Hphe, Nphe, and Cpheg with the highest separation factors (α) of 3.13, 2.10, 2.32, and 2.14, respectively. Taniaphos-Cu is more conducive to combine with D-amino acid in extraction. The influences of pH, Taniaphos-Cu, and concentration and extraction temperature on extraction were comprehensively evaluated. The highest performance factors (pf) for Phe, Hphe, Nphe, and Cpheg at optimal extraction conditions were 0.08892, 0.1250, 0.09621, and 0.08021, respectively. The recognition mechanism between Taniaphos-Cu and amino acid enantiomers was discussed. The coordination interaction between Taniaphos-Cu and -COO?, π-π interaction between Taniaphos-Cu and amino acid enantiomers are important acting forces in chiral extraction. The steric-hindrance between -NH2 and -OH lead to Taniaphos-Cu-D-Phe is more stable than Taniaphos-Cu-L-Phe. This work provided a chiral extractant that has good abilities to enantioseparate various amino acid enantiomers.

Reconstruction of Hyper-Thermostable Ancestral L-Amino Acid Oxidase to Perform Deracemization to D-Amino Acids

L-amino acid oxidases (LAAOs) with broad substrate specificity can be used in the deracemization of D,L-amino acids (D,L-AAs) to their D-enantiomers. Hyper-thermostable LAAO (HTAncLAAO) was designed through a combination of manual sequence data mining and ancestral sequence reconstruction. Soluble expression of HTAncLAAO (>50 mg/L) can be achieved using an E. coli system. HTAncLAAO, which recognizes seven L-AAs as substrates, exhibits extremely high thermal stability and long-term stability; the t1/2 value was 95 °C and 99 % ee, D-enantiomer). These results suggest that HTAncLAAO is an excellent biocatalyst to perform this deracemization.

Method for photolysis of amido bonds

The invention discloses a method for photo-splitting amido bonds, wherein the method is mild in reaction condition and can realize splitting of amido bonds by using illumination. The method for photo-splitting the amido bonds comprises the following steps: reacting 2,4-dinitrofluorobenzene with an amino group of a substance which contains alpha amino acid at the tail end and is shown as a structural formula I to generate a compound 1 represented by a structural formula II; and under light irradiation, carrying out amido bond cleavage reaction on the compound 1, wherein R1 is a side chain group of alpha-amino acid, and R2 is aryl, aliphatic hydrocarbon, -CH(R)-COOH or polypeptide.

Powerful Steroid-Based Chiral Selector for High-Throughput Enantiomeric Separation of α-Amino Acids Utilizing Ion Mobility-Mass Spectrometry

Stereospecific recognition of amino acids (AAs) plays a crucial role in chiral biomarker-based diagnosis and prognosis. Separation of AA enantiomers is a long and tedious task due to the requirement of AA derivatization prior to the chromatographic or electrophoretic steps which are also time-consuming. Here, a mass-tagged chiral selector named [d0]/[d5]-estradiol-3-benzoate-17β-chloroformate ([d0]/[d5]-17β-EBC) with high reactivity and good enantiomeric resolution in regard to AAs was developed. After a quick and easy chemical derivatization step of AAs using 17β-EBC as the single chiral selector before ion mobility-mass spectrometry analysis, good enantiomer separation was achieved for 19 chiral proteinogenic AAs in a single analytical run (～2 s). A linear calibration curve of enantiomeric excess was also established using [d0]/[d5]-17β-EBC. It was demonstrated to be capable of determining enantiomeric ratios down to 0.5% in the nanomolar range. 17β-EBC was successfully applied to investigate the absolute configuration of AAs among peptide drugs and detect trace levels of-AAs in complex biological samples. These results indicated that [d0]/[d5]-17β-EBC may contribute to entail a valuable step forward in peptide drug quality control and discovering chiral disease biomarkers.

Mechanically Strong Heterogeneous Catalysts via Immobilization of Powderous Catalysts to Porous Plastic Tablets

Main observation and conclusion: We describe a practical and general protocol for immobilization of heterogeneous catalysts to mechanically robust porous ultra-high molecular weight polyethylene tablets using inter-facial Lifshitz-van der Waals Interactions. Diverse types of powderous catalysts, including Cu, Pd/C, Pd/Al2O3, Pt/C, and Rh/C have been immobilized successfully. The immobilized catalysts are mechanistically robust towards stirring in solutions, and they worked well in diverse synthetic reactions. The immobilized catalyst tablets are easy to handle and reused. Moreover, the metal leaching of immobilized catalysts was reduced significantly.

SUPRAMOLECULAR GEL SUPPORTED ON OPEN-CELL POLYMER FOAM

The present invention relates to a polymer foam, said polymer foam comprising pores forming an open-cell polymer foam, said polymer foam comprising a supramolecular gel inside pores, and said polymer foam comprising at least one enzyme. The present invention relates to a supramolecular gel; its preparation and its applications, notably in chemical synthesis and kinetic resolution, in particular of organic compounds. The present invention also relates to flow chemistry.