3789-59-1

Usage

Uses

Used in the Food Industry:
(S)-(-)-1-Amino-1-phenylpropane is used as a key intermediate in the synthesis of L-Aspartyl-D-amino amide sweeteners. These sweeteners exhibit a sweetness potency 2000 times that of a 10% sucrose solution, making them highly valuable in the development of low-calorie and sugar-free products.
Used in the Pharmaceutical Industry:
(S)-(-)-1-Amino-1-phenylpropane serves as a molecular determinant of substrate specificity for transaminases, which are enzymes that play a crucial role in the biosynthesis and metabolism of various compounds, including drugs and natural products. Its chiral nature makes it an essential component in the development of enantiomerically pure pharmaceuticals.
Used in the Polymer Industry:
(S)-(-)-1-Amino-1-phenylpropane can be used to prepare optically active copolyacrylate polymers with sensing and chiroptical properties. These polymers have potential applications in the development of advanced materials for various industries, including electronics, sensors, and biotechnology.
Used in the Synthesis of Chiral Auxiliaries:
(S)-(-)-1-Amino-1-phenylpropane can be employed as a chiral auxiliary in the preparation of enantioenriched indanone-derived α-SCF2H β-keto esters. These chiral compounds are valuable in the synthesis of complex organic molecules, particularly in the pharmaceutical and agrochemical industries, where the development of enantiomerically pure compounds is of great importance.

Upstream product

• 31053-44-8 Propiophenonbenzoylhydrazon 
• 121328-37-8 (S)-4-Isopropyl-3-((R)-1-phenyl-propyl)-oxazolidin-2-one 
• 125402-82-6 (E)-1-phenylpropanone O-benzyl oxime 
• 89876-71-1 (2S,1'S)-N,3-dimethyl-N'-1'-phenylpropyl-2-hydrazinobutanol 
• 106651-15-4 (S)-N-(1-phenylpropyl)-P,P-diphenylphosphinamide 
• 226699-02-1 (S)-1-(4-chlorophenyl)-2-propynylamine 
• 154675-31-7 N-[1-(phenyl)propyl]-P,P-diphenylphosphinoylamide 
• 93-55-0 1-phenyl-propan-1-one 
• 2941-20-0 1-phenylpropylamine 
• 498542-91-9 (1S,2S)-N-acetyl-1,2-bis(trifluoromethanesulfonamido) cyclohexane 
• 557-20-0 diethylzinc 
• 186249-76-3 (R,E)-2-methyl-N-(phenylmethylene)-2-propanesulfinamide 
• 98837-46-8 N-benzylidenediphenylphosphinamide 
• 98-86-2 acetophenone 

Downstream Products

• 19146-53-3 (S)-α-cyclohexylethylamine 
• 141178-36-1 (-)-N-(1-phenylpropyl)propionamide 
• 141178-38-3 (-)-N-(1-phenylpropyl)trimethylacetamide 
• 74879-41-7 [1-(4-Methoxy-phenyl)-meth-(E)-ylidene]-((S)-1-phenyl-propyl)-amine 
• 3082-66-4 (S)-N-salicylidine-1-phenylpropylamine 
• 77855-49-3 N-<(S)-α-ethylbenzyl>pyruvamide 
• 141178-37-2 (-)-N-(1-phenylpropyl)isobutyramide 
• 87858-37-5 (S)-N-(1-phenylpropyl)formamide 
• 154653-36-8 N-(carbobenzyloxy)-β-benzyl-L-aspartyl-D-α-aminobutyric acid (S)-α-ethylbenzylamide 
• 165055-18-5 N-CBZ-β-benzyl-L-aspartyl-D-valine (S)-α-ethylbenzylamide 
• 189878-81-7 [(R)-1-((S)-1-Phenyl-propylcarbamoyl)-propyl]-carbamic acid benzyl ester 
• 174636-20-5 2-phenyl-4-(carboxy-(S)-α-ethylbenzylamine)quinoline 
• 174636-32-9 talnetant 
• 174636-16-9 (-)-(S)-N-(α-ethylbenzyl)-3-amino-2-phenylquinoline-4-carboxamide 

Relevant academic research and scientific papers

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.

Generation of Oxidoreductases with Dual Alcohol Dehydrogenase and Amine Dehydrogenase Activity

The l-lysine-?-dehydrogenase (LysEDH) from Geobacillus stearothermophilus naturally catalyzes the oxidative deamination of the ?-amino group of l-lysine. We previously engineered this enzyme to create amine dehydrogenase (AmDH) variants that possess a new hydrophobic cavity in their active site such that aromatic ketones can bind and be converted into α-chiral amines with excellent enantioselectivity. We also recently observed that LysEDH was capable of reducing aromatic aldehydes into primary alcohols. Herein, we harnessed the promiscuous alcohol dehydrogenase (ADH) activity of LysEDH to create new variants that exhibited enhanced catalytic activity for the reduction of substituted benzaldehydes and arylaliphatic aldehydes to primary alcohols. Notably, these novel engineered dehydrogenases also catalyzed the reductive amination of a variety of aldehydes and ketones with excellent enantioselectivity, thus exhibiting a dual AmDH/ADH activity. We envisioned that the catalytic bi-functionality of these enzymes could be applied for the direct conversion of alcohols into amines. As a proof-of-principle, we performed an unprecedented one-pot “hydrogen-borrowing” cascade to convert benzyl alcohol to benzylamine using a single enzyme. Conducting the same biocatalytic cascade in the presence of cofactor recycling enzymes (i.e., NADH-oxidase and formate dehydrogenase) increased the reaction yields. In summary, this work provides the first examples of enzymes showing “alcohol aminase” activity.

Simultaneous Preparation of (S)-2-Aminobutane and d -Alanine or d -Homoalanine via Biocatalytic Transamination at High Substrate Concentration

(S)-2-Aminobutane, d-alanine, and d-homoalanine are important intermediates for the production of various active pharmaceutical ingredients and food additives. The preparation of these small chiral amine or amino acids with high water solubility still demands searching for efficient methods. In this work, we identified an ω-transaminase (ω-TA) from Sinirhodobacter hungdaonensis (ShdTA) that catalyzed the kinetic resolution of racemic 2-aminobutane at a concentration of 800 mM using pyruvate as the amino acceptor, leading to the simultaneous isolation of enantiopure (S)-2-aminobutane and d-alanine in 46% and 90% yield, respectively. In addition, (S)-2-aminobutane (98% ee) and d-homoalanine (99% ee) were isolated in 45% and 93% yield, respectively, in the kinetic resolution of racemic 2-aminobutane at a concentration of 400 mM coupled with deamination of l-threonine by threonine deaminase. We thus developed a biocatalytic process for the practical synthesis of these valuable small chiral amine and d-amino acids.

Engineering the large pocket of an (S)-selective transaminase for asymmetric synthesis of (S)-1-amino-1-phenylpropane

Amine transaminases offer an environmentally benign chiral amine asymmetric synthesis route. However, their catalytic efficiency towards bulky chiral amine asymmetric synthesis is limited by the natural geometric structure of the small pocket, representing a great challenge for industrial applications. Here, we rationally engineered the large binding pocket of an (S)-selective ?-transaminase BPTA fromParaburkholderia phymatumto relieve the inherent restriction caused by the small pocket and efficiently transform the prochiral aryl alkyl ketone 1-propiophenone with a small substituent larger than the methyl group. Based on combined molecular docking and dynamic simulation analyses, we identified a non-classical substrate conformation, located in the active site with steric hindrance and undesired interactions, to be responsible for the low catalytic efficiency. By relieving the steric barrier with W82A, we improved the specific activity by 14-times compared to WT. A p-p stacking interaction was then introduced by M78F and I284F to strengthen the binding affinity with a large binding pocket to balance the undesired interactions generated by F44. T440Q further enhanced the substrate affinity by providing a more hydrophobic and flexible environment close to the active site entry. Finally, we constructed a quadruple variant M78F/W82A/I284F/T440Q to generate the most productive substrate conformation. The 1-propiophenone catalytic efficiency of the mutant was enhanced by more than 470-times in terms ofkcat/KM, and the conversion increased from 1.3 to 94.4% compared with that of WT, without any stereoselectivity loss (ee > 99.9%). Meanwhile, the obtained mutant also showed significant activity improvements towards various aryl alkyl ketones with a small substituent larger than the methyl group ranging between 104- and 230-fold, demonstrating great potential for the efficient synthesis of enantiopure aryl alkyl amines with steric hindrance in the small binding pocket.

Combined Theoretical and Experimental Studies Unravel Multiple Pathways to Convergent Asymmetric Hydrogenation of Enamides

We present a highly efficient convergent asymmetric hydrogenation of E/Z mixtures of enamides catalyzed by N,P-iridium complexes supported by mechanistic studies. It was found that reduction of the olefinic isomers (E and Z geometries) produces chiral amides with the same absolute configuration (enantioconvergent hydrogenation). This allowed the hydrogenation of a wide range of E/Z mixtures of trisubstituted enamides with excellent enantioselectivity (up to 99% ee). A detailed mechanistic study using deuterium labeling and kinetic experiments revealed two different pathways for the observed enantioconvergence. For α-aryl enamides, fast isomerization of the double bond takes place, and the overall process results in kinetic resolution of the two isomers. For α-alkyl enamides, no double bond isomerization is detected, and competition experiments suggested that substrate chelation is responsible for the enantioconvergent stereochemical outcome. DFT calculations were performed to predict the correct absolute configuration of the products and strengthen the proposed mechanism of the iridium-catalyzed isomerization pathway.

Asymmetric synthesis of primary amines catalyzed by thermotolerant fungal reductive aminases

Chiral primary amines are important intermediates in the synthesis of pharmaceutical compounds. Fungal reductive aminases (RedAms) are NADPH-dependent dehydrogenases that catalyse reductive amination of a range of ketones with short-chain primary amines supplied in an equimolar ratio to give corresponding secondary amines. Herein we describe structural and biochemical characterisation as well as synthetic applications of two RedAms fromNeosartoryaspp. (NfRedAm andNfisRedAm) that display a distinctive activity amongst fungal RedAms, namely a superior ability to use ammonia as the amine partner. Using these enzymes, we demonstrate the synthesis of a broad range of primary amines, with conversions up to >97% and excellent enantiomeric excess. Temperature dependent studies showed that these homologues also possess greater thermal stability compared to other enzymes within this family. Their synthetic applicability is further demonstrated by the production of several primary and secondary amines with turnover numbers (TN) up to 14 000 as well as continous flow reactions, obtaining chiral amines such as (R)-2-aminohexane in space time yields up to 8.1 g L?1h?1. The remarkable features ofNfRedAmand NfisRedAm highlight their potential for wider synthetic application as well as expanding the biocatalytic toolbox available for chiral amine synthesis.

A Simple Biosystem for the High-Yielding Cascade Conversion of Racemic Alcohols to Enantiopure Amines

The amination of racemic alcohols to produce enantiopure amines is an important green chemistry reaction for pharmaceutical manufacturing, requiring simple and efficient solutions. Herein, we report the development of a cascade biotransformation to aminate racemic alcohols. This cascade utilizes an ambidextrous alcohol dehydrogenase (ADH) to oxidize a racemic alcohol, an enantioselective transaminase (TA) to convert the ketone intermediate to chiral amine, and isopropylamine to recycle PMP and NAD+ cofactors via the reversed cascade reactions. The concept was proven by using an ambidextrous CpSADH-W286A engineered from (S)-enantioselective CpSADH as the first example of evolving ambidextrous ADHs, an enantioselective BmTA, and isopropylamine. A biosystem containing isopropylamine and E. coli (CpSADH-W286A/BmTA) expressing the two enzymes was developed for the amination of racemic alcohols to produce eight useful and high-value (S)-amines in 72–99 % yield and 98–99 % ee, providing with a simple and practical solution to this type of reaction.

Kinetic Resolution of Racemic Primary Amines Using Geobacillus stearothermophilus Amine Dehydrogenase Variant

A NADH-dependent engineered amine dehydrogenase from Geobacillus stearothermophilus (LE-AmDH-v1) was applied together with a NADH-oxidase from Streptococcus mutans (NOx) for the kinetic resolution of pharmaceutically relevant racemic α-chiral primary amines. The reaction conditions (e. g., pH, temperature, type of buffer) were optimised to yield S-configured amines with up to >99 % ee.

Generation of amine dehydrogenases with increased catalytic performance and substrate scope from ε-deaminating L-Lysine dehydrogenase

Amine dehydrogenases (AmDHs) catalyse the conversion of ketones into enantiomerically pure amines at the sole expense of ammonia and hydride source. Guided by structural information from computational models, we create AmDHs that can convert pharmaceutically relevant aromatic ketones with conversions up to quantitative and perfect chemical and optical purities. These AmDHs are created from an unconventional enzyme scaffold that apparently does not operate any asymmetric transformation in its natural reaction. Additionally, the best variant (LE-AmDH-v1) displays a unique substrate-dependent switch of enantioselectivity, affording S- or R-configured amine products with up to >99.9% enantiomeric excess. These findings are explained by in silico studies. LE-AmDH-v1 is highly thermostable (Tm of 69 °C), retains almost entirely its catalytic activity upon incubation up to 50 °C for several days, and operates preferentially at 50 °C and pH 9.0. This study also demonstrates that product inhibition can be a critical factor in AmDH-catalysed reductive amination.

One-Pot Transformation of Ketoximes into Optically Active Alcohols and Amines by Sequential Action of Laccases and Ketoreductases or ω-Transaminases

An enzymatic one-pot process for asymmetric transformation of prochiral ketoximes into alcohols or amines was developed by sequential coupling of a laccase-catalyzed deoximation either with a ketone reduction (ketoreductase, KRED) or bioamination (ω-transaminase, ω-TA) in aqueous medium. An accurate selection of biocatalysts provided the corresponding products in excellent enantiomeric excesses and overall conversions ranging from 83 to >99 % for alcohols and 70 to >99 % for amines. Likewise, the employment of exclusively 1 % (w/w) of Cremophor, a polyethoxylated castor oil, as co-solvent enabled to reach concentrations up to 100 mM in the chiral alcohols cascade.