cas 13250-12-9, (R)-(-)-2-Aminobutane | Articles data

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Preparation of (R)-amines from racemic amines with an (S)-amine transaminase from Bacillus megaterium
Screening was carried out to identify strains useful for the preparation of (R)-1-cyclopropylethylamine and (R)-sec-butylamine by resolution of the racemic amines with an (S)-specific transaminase. Several Bacillus megaterium strains from our culture collection as well as several soil isolates were found to have the desired activity for the resolution of the racemic amines to give the (R)-enantiomers. Using an extract of the best strain, Bacillus megaterium SC6394, the reaction was shown to be a trans-amination requiring pyruvate as amino acceptor and pyridoxal phosphate as a cofactor. Initial batches of both amines were produced using whole cells of Bacillus megaterium SC6394. The transaminase was purified to homogeneity to obtain N-terminal as well as internal amino acid sequences. The sequences were used to design polymerase chain reaction (PCR) primers to enable cloning and expression of the trans-aminase in E. coli SC16578. In contrast to the original B. megaterium process, pH control and aeration were not required for the resolution of sec-butyl-amine and an excess of pyruvate was not consumed by the recombinant cells. The resolution of sec-butylamine (0.68M) using whole cells of E. coli SC16578 was scaled up to give (R)-sec-butylamine·1/2 H2SO 4 in 46.6% isolated yield with 99.2% ee. An alternative isolation procedure was also used to isolate (R)-secbutylamine as the free base.
Hanson, Ronald L.,Davis, Brian L.,Chen, Yijun,Goldberg, Steven L.,Parker, William L.,Tully, Thomas P.,Montana, Michael A.,Patel, Ramesh N.
p. 1367 - 1375
(2008)
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Identification of novel thermostable ω-transaminase and its application for enzymatic synthesis of chiral amines at high temperature
A novel thermostable ω-transaminase from Thermomicrobium roseum which showed broad substrate specificity and high enantioselectivity was identified, expressed and biochemically characterized. The advantage of this enzyme to remove volatile inhibitory by-products was demonstrated by performing asymmetric synthesis and kinetic resolution at high temperature.
Mathew, Sam,Deepankumar, Kanagavel,Shin, Giyoung,Hong, Eun Young,Kim, Byung-Gee,Chung, Taeowan,Yun, Hyungdon
p. 69257 - 69260
(2016)
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Enzymatic resolution of sec-butylamine
Resolution of (±)-sec-butylamine by Candida antarctica lipase provided a very low enantiomeric excess of the residual amine when either ethyl or vinyl butyrate was used as the acylating agent. The enantiomeric excess was increased by using ethyl esters of long chain fatty acids. The rate of the reaction was increased by using methyl t-butyl ether as a solvent. (S)-sec-Butylamine of very high enantiomeric excess was obtained by C. antarctica lipase catalyzed acylation with ethyl decanoate in methyl t-butyl ether.
Goswami, Animesh,Guo, Zhiwei,Parker, William L.,Patel, Ramesh N.
p. 1715 - 1719
(2005)
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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.
Li, Jianjiong,Wang, Yingang,Wu, Qiaqing,Yao, Peiyuan,Yu, Shanshan,Zhu, Dunming
supporting information

(2022/03/01)

Ruthenium Catalyzed Direct Asymmetric Reductive Amination of Simple Aliphatic Ketones Using Ammonium Iodide and Hydrogen
The direct conversion of ketones into chiral primary amines is a key transformation in chemistry. Here, we present a ruthenium catalyzed asymmetric reductive amination (ARA) of purely aliphatic ketones with good yields and moderate enantioselectivity: up to 99 percent yield and 74 percent ee. The strategy involves [Ru(PPh3)3H(CO)Cl] in combination with the ligand (S,S)-f-binaphane as the catalyst, NH4I as the amine source and H2 as the reductant. This is a straightforward and user-friendly process to access industrially relevant chiral aliphatic primary amines. Although the enantioselectivity with this approach is only moderate, to the extent of our knowledge, the maximum ee of 74 percent achieved with this system is the highest reported till now apart from enzyme catalysis for the direct transformation of ketones into chiral aliphatic primary amines.
Ernst, Martin,Ghosh, Tamal,Hashmi, A. Stephen K.,Schaub, Thomas
supporting information

(2020/07/14)

Separate Sets of Mutations Enhance Activity and Substrate Scope of Amine Dehydrogenase
Mutations were introduced into the leucine amine dehydrogenase (L-AmDH) derived from G. stearothermophilus leucine dehydrogenase (LeuDH) with the goals of increased activity and expanded substrate acceptance. A triple variant (L-AmDH-TV) including D32A, F101S, and C290V showed an average of 2.5-fold higher activity toward aliphatic ketones and an 8.0 °C increase in melting temperature. L-AmDH-TV did not show significant changes in relative activity for different substrates. In contrast, L39A, L39G, A112G, and T133G in varied combinations added to L-AmDH-TV changed the shape of the substrate binding pocket. L-AmDH-TV was not active on ketones larger than 2-hexanone. L39A and L39G enabled activity for straight-chain ketones as large as 2-decanone and in combination with A112G enabled activity toward longer branched ketones including 5-methyl-2-octanone.
Franklin, Robert D.,Mount, Conner J.,Bommarius, Bettina R.,Bommarius, Andreas S.
p. 2436 - 2439
(2020/04/16)

Deracemization of Racemic Amines to Enantiopure (R)- and (S)-amines by Biocatalytic Cascade Employing ω-Transaminase and Amine Dehydrogenase
A one-pot deracemization strategy for α-chiral amines is reported involving an enantioselective deamination to the corresponding ketone followed by a stereoselective amination by enantiocomplementary biocatalysts. Notably, this cascade employing a ω-transaminase and amine dehydrogenase enabled the access to both (R)-and (S)-amine products, just by controlling the directions of the reactions catalyzed by them. A wide range of (R)-and (S)-amines was obtained with excellent conversions (>80 %) and enantiomeric excess (>99 % ee). Finally, preparative scale syntheses led to obtain enantiopure (R)- and (S)-13 with the isolated yields of 53 and 75 %, respectively.
Yoon, Sanghan,Patil, Mahesh D.,Sarak, Sharad,Jeon, Hyunwoo,Kim, Geon-Hee,Khobragade, Taresh P.,Sung, Sihyong,Yun, Hyungdon
p. 1898 - 1902
(2019/02/27)

(R)- SELECTIVE AMINATION
The present invention relates to a method for the enzymatic synthesis of enantiomerically enriched (R)-amines of general formula [1][c] from the corresponding ketones of the general formula [1][a] by using novel transaminases. These novel transaminases are selected from two different groups: either from a group of some 20 proteins with sequences as specified herein, or from a group of proteins having transaminase activity and isolated from a microorganism selected from the group of organisms consisting of Rahnella aquatilis, Ochrobactrum anthropi, Ochrobactrum tritici, Sinorhizobium morelense, Curtobacterium pusiffium, Paecilomyces lilacinus, Microbacterium ginsengisoli, Microbacterium trichothecenolyticum, Pseudomonas citronellolis, Yersinia kristensenii, Achromobacter spanius, Achromobacter insolitus, Mycobacterium fortuitum, Mycobacterium frederiksbergense, Mycobacterium sacrum, Mycobacterium fluoranthenivorans, Burkhoideria sp., Burkhoideria tropica, Cosmospora episphaeria, and Fusarium oxysporum.
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Paragraph 0120; 0121; 0122

(2016/03/22)

The influence of conventional heating and microwave irradiation on the resolution of (RS)-sec-butylamine catalyzed by free or immobilized lipases
The lipases CAL-B, PSL, PSL-C, PSL-D, and A. niger lipase, free or immobilized in starch (obtained from two types of yam, known in Brazil as cara? (Discorea alata L.) and inhame (Colocasia esculenta (L.) Schott) or gelatin films, were used in the acylation of (RS)-sec-butylamine with different acyl donors in various organic solvents applying conventional heating (CH) or microwave (MW) irradiation. In the case of free A. niger lipase, the conversion degrees were three times higher using MW irradiation when compared to conventional heating at 35 °C. Using free A. niger lipase, the (R)-amide was obtained with a conversion degree of 21percent, resulting in eep > 99percent and E-value (enantioselectivity value) > 200, in 1 min of reaction under MW irradiation. When the A. niger lipase was immobilized in yam starch films, the (R)-amide was obtained in moderate conversions of 8-25percent after 3 or 5 min of reaction under MW irradiation, but with higher selectivity (eep > 99percent and E > 200) in comparison with the free form (conversion degree of 45percent, eep 81percent and E value of 18).
Pilissa?o, Cristiane,De Oliveira Carvalho, Patri?cia,Da Grac?a Nascimento, Maria
p. 1688 - 1697
(2013/01/15)

ω-Transaminase-catalyzed kinetic resolution of chiral amines using l-threonine as an amino acceptor precursor
Kinetic resolution of chiral amines using l-threonine as a cosubstrate was demonstrated by a biocatalytic strategy in which (S)-selective ω-transaminase (ω-TA) was coupled with threonine deaminase (TD), eliminating the need to use an expensive keto acid as an amino acceptor. The coupled enzyme reaction enabled simultaneous production of enantiopure (R)-amine and l-homoalanine which are pharmaceutically important building blocks. To extend the versatility of this strategy to production of both enantiomers of chiral amines, (R)-selective ω-TA coupled with TD was employed to produce (S)-amine.
Malik, M. Shaheer,Park, Eul-Soo,Shin, Jong-Shik
supporting information; experimental part
p. 2137 - 2140
(2012/09/25)

Stereoselectivity of four (R)-selective transaminases for the asymmetric amination of ketones
Four (R)-ω-transaminases originating from Hyphomonas neptunium (HN-ωTA), Aspergillus terreus (AT-ωTA) and Arthrobacter sp. (ArR-ωTA), as well as an evolved transaminase (ArRmut11-ωTA) were successfully employed for the amination of prochiral ketones leading to optically pure (R)-amines. The first three transaminases displayed perfect stereoselectivity for the amination of all substrates tested (ee >99%). Furthermore, the transaminase AT-ωTA led in most cases to better conversion than ArR-ωTA and HN-ωTA using D-alanine as amine donor. α-Tetralone, which was the only substrate not accepted by HN-ωTA, ArR-ωTA, and AT-ωTA, was successfully transformed with perfect enantioselectivity (ee >99%) into the corresponding optically pure amine employing the variant ArRmut11-ωTA. Copyright
Mutti, Francesco G.,Fuchs, Christine S.,Pressnitz, Desiree,Sattler, Johann H.,Kroutil, Wolfgang
experimental part
p. 3227 - 3233
(2012/01/03)

Chemoenzymatic dynamic kinetic resolution of primary amines catalyzed by CAL-B at 38-40°c
The (R)-selective chemoenzymatic dynamic kinetic resolution of primary amines was performed at 38-40 °C in MTBE, in good to high yields and with high enantiomeric excesses. These reactions associating CAL-B to octanethiol as radical racemizing agent were carried out in the presence of methyl β-methoxy propanoate as acyl donor, under photochemical irradiation at 350 nm in glassware.
Poulhes, Florent,Vanthuyne, Nicolas,Bertrand, Michele P.,Gastaldi, Stephane,Gil, Gerard
experimental part
p. 7281 - 7286
(2011/10/10)

Unprecedented gas-phase chiroselective logic gates
The gas-phase encounters between 2-aminobutane and proton-bound chiral resorcin[4]arene/nucleoside complexes behave in the gas phase as supramolecular "chiroselective logic gates" by releasing the nucleoside depending on the resorcin[4]arene and the 2-aminobutane configurations.
Botta, Bruno,Fraschetti, Caterina,D'Acquarica, Ilaria,Sacco, Fabiola,Mattay, Jochen,Letzel, Matthias C.,Speranza, Maurizio
supporting information; experimental part
p. 1717 - 1719
(2011/05/03)

Deracemisation of α-chiral primary amines by a one-pot, two-step cascade reaction catalysed by ω-transaminases
Racemic a-chiral primary amines were deracemised to optically pure amines in up to >99 % conversion and >99 % ee within 48 h. The deracemisation was a result of a stereoinver- sion of one amine enantiomer; the formal stereoinversion was achieved by a one-pot, two-step procedure: in the first step, kinetic resolution of the chiral racemic amine was performed by employing a -transaminase to yield an intermediate ketone and the remaining optically pure amine; in the second step, the ketone intermediate was stereoselectively transformed into the amine by employing alanine as the amine donor and a -transaminase displaying opposite stereopref- erence than the -transaminase in the first step. In the second step, lactate dehydrogenase was used to remove the side product pyruvate to shift the unfavourable reaction equilibrium to the product side. Depending on the order of the en- antiocomplementary enzymes employed in the cascade, the (R), as well as the (S), enantiomer was accessible.
Koszelewski, Dominik,Clay, Dorina,Rozzell, David,Kroutil, Wolfgang
experimental part
p. 2289 - 2292
(2009/08/09)

Enantioselective benzoylation of racemic amines using chiral benzimidazolide as a benzoylating agent
Enantioselective acylation/kinetic resolution of racemic amines has been achieved by using a chiral benzimidazolide, namely, (S)-1-benzoyl-2-(α-acetoxyethyl)benzimidazole 2. This nonenzymatic acylating reagent requires mild reaction conditions and proceeds with good enantioselectivity.
Karnik, Anil V.,Kamath, Suchitra S.
p. 45 - 48
(2008/09/17)

Highly selective enzymatic kinetic resolution of primary amines at 80°C: A comparative study of carboxylic acids and their ethyl esters as acyl donors
(Chemical Equation Presented) Optimization of the kinetic resolution of 2-amino-4-phenyl-butane was achieved at 80°C using CAL-B-catalyzed aminolysis of carboxylic acids and their ethyl esters. The reactions carried out with long chain esters and the corresponding acids as acyl donors proceeded with remarkably high enantioselectivity. The use of carboxylic acids as acylating agents led to a marked acceleration of the reaction rate compared to their ester counterparts. Laurie acid led to enantiomeric excesses superior to 99.5% for both the remaining amine and the corresponding lauramide at 50% conversion (reached in 3 h). These optimized conditions were applied to the resolution of a series of aliphatic and benzylic amines.
Nechab, Malek,Azzi, Nadia,Vanthuyne, Nicolas,Bertrand, Michele,Gastaldi, Stephane,Gil, Gerard
p. 6918 - 6923
(2008/02/11)

Comparison of the ω-transaminases from different microorganisms and application to production of chiral amines
Microorganisms that are capable of (S)-enantioselective transamination of chiral amines were isolated from soil samples by selective enrichment using (S)-α-methylbenzylamine ((S)-α-MBA) as a sole nitrogen source. Among them, Klebsiella pneumoniae JS2F, Bacillus thuringiensis JS64, and Vibrio fluvialis JS17 showed good ω-transaminase (ω-TA) activities and the properties of the ω-TAs were investigated. The induction level of the enzyme was strongly dependent on the nitrogen source for the strains, except for V. fluvialis JS17. All the ω-TAs showed high enantioselectivity (E>50) toward (S)-α-MBA and broad amino donor specificities for arylic and aliphatic chiral amines. Besides pyruvate, aldehydes such as propionaldehyde and butyraldehyde showed good amino acceptor reactivities. All the ω-TAs showed substrate inhibition by (S)-α-MBA above 200 mM. Moreover, substrate inhibition by pyruvate above 10 mM was observed for ω-TA from V. fluvialis JS17. In the case of product inhibition, acetophenone showed much greater inhibitions than L-alanine for all ω-TAs. Comparison of the enzyme properties indicates that ω-transaminase from V. fluvialis JS17 is the best one for both kinetic resolution and asymmetric synthesis to produce enantiomerically pure chiral amines. Kinetic resolution of sec-butylamine (20 mM) was done under reduced pressure (150 Torr) to selectively remove an inhibitory product (2-butanone) using the enzyme from V. fluvialis JS17. Enantiomeric excess of (R)-sec-butylamine reached 94.7% after 12 h of reaction.
Shin, Jong-Shik,Kim, Byung-Gee
p. 1782 - 1788
(2007/10/03)

Enantioselective synthesis of α,α-disubstituted amines from nitroalkenes
Disubstituted nitroalkenes were converted into enantiomerically enriched amines (isolated as their hydrochloride salts) with enantiometric excesses of 88 to >95% in there steps: (a) highly stereoselective conjugate addition of the potassium salt of 4-phenyloxazolidin-2-one; (b) radical-mediated removal of the nitro group; (c) cleavage of the oxazolidinone.
Leroux, Mary-Lorene,Le Gall, Thierry,Mioskowski, Charles
p. 1817 - 1823
(2007/10/03)

Resolution of chiral aliphatic and arylalkyl amines using immobilized Candida antarctica lipase and isolation of their R- and S-enantiomers
The resolution of chiral aliphatic and arylalkyl amines in high enantiomeric excess (up to 97.5% ee for the R-enantiomers and up to 99.9% ee for the S-enantiomers) and good yield (50-80%) using immobilized Candida antarctica lipase and ethyl acetate as acyl donor has been demonstrated. A second resolution on the Ramine increased the enantiomeric excess to more than 99.5% (up to 99.9%).
Davis,Durden
p. 569 - 578
(2007/10/03)

CD OF PRIMARY AMINES AND 1- OR 3-SUBSTITUTED TETRAHYDROISOQUINOLINES IN PRESENCE OF
The syntheses of (S)-(-)-1,2-dimethyl-1,2,3,4-tetrahydroisoquinoline (IX) and S-(+)-2,3-dimethyl-1,2,3,4-tetrahydroisoquinoline (XVI) in optically pure form and with known absolute configuration is described.The CD and NMR spectra of these compounds and of most of their intermediates are given, and from these data could be deduced, that the N-methyl groups of the two bases IX and XVI adopt different conformations in solution, but the same (viz. axial) in their complexes with .
Diener, Wolfgang,Frelek, Jadwiga,Snatzke, Guenther
p. 954 - 965
(2007/10/02)

Synthesis of (R)- and (S)-2-Aminobutane from (S)- and (R)-2-Aminobutanol
(R)-(-)- and (S)-(+)-2-Aminobutane (1) can be synthesized in good yield and high optical purity from (S)-(+)- and (R)-(-)-2-aminobutanol (2) respectively.
Santaniello, Enzo,Casati, Rosangela,Milani, Fulvia
p. 919 - 922
(2007/10/02)

Asymmetric Syntheses. Part 11. Reduction of Ketones and Related Ketone Oximes with Lithium Aluminium Hydride-3-O-cyclohexylmethyl-1,2-O-cyclohexylidene-α-D-glucofuranose Complex to give Optically Active Alcohols and Amines
The asymmetric reduction of ketones and structurally related isoelectronic ketone oximes with lithium aluminium hydride-3-O-cyclohexylmethyl-1,2-O-cyclohexylidene-α-D-glucofuranose complex yields optically active alcohols of up to 42percent optical purity and optically active amines of up to 52percent optical purity, respectively.The resulting alcohols as well as amines all have the S-configuration.When the asymmetric reduction is carried out with the ethanol-modified glucofuranose complex, the resulting alcohols and amines have the R-configuration.
Landor, Stephen R.,Chan, Yuet M.,Sonola, Olutunji O.,Tatchell, Austin R.
p. 493 - 496
(2007/10/02)