14590-53-5Relevant articles and documents
The synthesis of S-(+)-2,2-dimethylcyclopropane carboxylic acid: A precursor for cilastatin
Wang, Qinwei,Yang, Fukang,Du, Hong,Hossain, M. Mahmun,Bennett, Dennis,Grubisha, Desiree S.
, p. 3971 - 3977 (1998)
S-(+)-2,2-Dimethylcyclopropane carboxylic acid, a precursor for cilastatin, was prepared from 2-methylpropene and chiral iron carbene in three steps. Asymmetric cyclopropanation reaction of 2-methylpropene with iron carbene complex having chirality at the carbene ligand, followed by exhaustive ozonolysis, produced S-(+)-2,2-dimethylcyclopropanecarboxylic acid of up to 92% ee. The absolute configuration of complexed chiral cyclopropane (-)-8 was determined by X-ray crystallographic analysis.
Soluble and functional expression of a recombinant enantioselective amidase from Klebsiella oxytoca KCTC 1686 in Escherichia coli and its biochemical characterization
Guo, Fa-Mou,Wu, Jian-Ping,Yang, Li-Rong,Xu, Gang
, p. 1264 - 1271 (2015/07/08)
A gene encoding an enantioselective amidase (KamH) was cloned from Klebsiella oxytoca KCTC 1686 and inserted into the EcoRI and HindIII sites of the vector pET-30a(+). When KamH with a peptide containing a His-tag and an enterokinase cleavage site was overexpressed in Escherichia coli, approximately half was found in the soluble fraction, but it lacked activity. After cleavage of the peptide by enterokinase, the enzyme activity was partly restored, reaching 420.2 ± 33.62 U/g dry cell weight (DCW). Another recombinant plasmid was constructed by inserting the KamH gene into the NdeI and EcoRI sites of pET-30a(+) to express KamH in its native form. The overexpressed amidase was found primarily in the soluble fraction and its maximum activity was 3613.4 ± 201.68 U/g DCW. This indicated that the peptide influenced not only soluble expression but also activity of KamH, perhaps by blocking the substrate-binding tunnel of KamH. Similar results were obtained with heterologously expressed amidases from Rhodococcus erythropolis MP50 and Agrobacterium tumefaciens d3. All of these amidases have an N-terminal α-helical domain. Therefore, amidases of this type may be functionally expressed in their native form. KamH hydrolyzed a range of aliphatic and aromatic amides and exhibited strict S-selectivity towards racemic amides.
Production of L-tryptophan by enantioselective hydrolysis of d,l-tryptophanamide using a newly isolated bacterium
Xu, Jian-Miao,Chen, Ben,Wang, Yuan-Shan,Zheng, Yu-Guo
, p. 1262 - 1270 (2013/07/19)
Bacterial strain ZJB-09211 capable of amidase production has recently been isolated from soil samples. The strain is able to asymmetrically hydrolyze l-tryptophanamide from d,l-tryptophanamide to produce l-tryptophan in high yield and with excellent stereoselectivity (enantiomeric excess > 99.9 %, and enantiomeric ratio > 200). Strain ZJB-09211 has been identified as Flavobacterium aquatile based on the cell morphology analysis, physiological tests, and the 16S rDNA sequence analysis. Optimization of the fermentation medium led to an about six-fold increase in the amidase activity of strain ZJB-09211, which reached 501.5 U L-1. Substrate specifity and stereoselectivity investigations revealed that amidase of F. aquatile possessed a broad substrate spectrum and high enantioselectivity.
PROCESS FOR PRODUCTION OF OPTICALLY ACTIVE CARBOXYLIC ACID
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Page 8, (2008/06/13)
The invention provides a process for producing optically active 2, 2-dimethylcyclopropanecarboxylic acid by reacting an optical isomer mixture of 2,2-dimethylcyclopropanecarboxylic acid with an optically inactive amine to form (precipitate, crystallize or the like) an ammonium salt of optically active 2,2-dimethylcyclopropanecarboxylic acid, for example, optically active (S)-(+)-2,2-dimethylcyclopropanecarboxylic acid. The production (optical resolution, separation of an optically active substance, purification of an optically active substance or the like) of optically active 2, 2-dimethylcyclopropanecarboxylic acid which is important as an intermediate for production of agricultural chemicals, medications and the like can easily be conducted at low cost. Further, the invention provides an intermediate therefor (an ammonium salt of optically active 2,2-dimethylcyclopropanecarboxylic acid, especially preferably an ammonium salt of optically active (S)-(+)-2,2-dimethylcyclopropanecarboxylic acid, or the like), and an optical resolution agent (optically inactive amine) for separation of optically active 2,2-dimethylcyclopropanecarboxylic acid.