123-82-0Relevant articles and documents
Reshaping the Active Pocket of Amine Dehydrogenases for Asymmetric Synthesis of Bulky Aliphatic Amines
Chen, Fei-Fei,Zheng, Gao-Wei,Liu, Lei,Li, Hao,Chen, Qi,Li, Fu-Long,Li, Chun-Xiu,Xu, Jian-He
, p. 2622 - 2628 (2018)
The asymmetric reductive amination of ketones with ammonia using engineered amine dehydrogenases (AmDHs) is a particularly attractive and environmentally friendly method for the synthesis of chiral amines. However, one major challenge for these engineered AmDHs is their limited range of accepted substrates. Herein, several engineered AmDHs were developed through the evolution of naturally occurring leucine dehydrogenases, which displayed good amination activity toward aliphatic ketones but restricted catalytic scope for short-chain substrates. Computational analysis helped identify two residues, located at the distal end of the substrate-binding cavity, that generate steric hindrance and prevent the binding of bulky aliphatic ketones. By fine-tuning these two key hotspots, the resulting AmDH mutants are able to accept previously inaccessible bulky substrates. More importantly, the mutations were also proved applicable for expanding the substrate scope of other homologous AmDHs with sequence identities as low as 70%, indicating a broad effect on the development of AmDHs and the synthesis of structurally diverse chiral amines.
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Mazur,R.H.
, p. 2050 - 2051 (1970)
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Simultaneous Preparation of (S)-2-Aminobutane and d -Alanine or d -Homoalanine via Biocatalytic Transamination at High Substrate Concentration
Li, Jianjiong,Wang, Yingang,Wu, Qiaqing,Yao, Peiyuan,Yu, Shanshan,Zhu, Dunming
supporting information, (2022/03/01)
(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.
Ruthenium Catalyzed Direct Asymmetric Reductive Amination of Simple Aliphatic Ketones Using Ammonium Iodide and Hydrogen
Ernst, Martin,Ghosh, Tamal,Hashmi, A. Stephen K.,Schaub, Thomas
supporting information, (2020/07/14)
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.