51380-14-4

Upstream product

• 395-35-7 4-(trifluoromethyl)mandelic acid 
• 108-05-4 vinyl acetate 
• 79478-02-7 4-(trifluoromethyl)phenylglyoxylic acid 
• 142044-52-8 2-Fluoro-2-(4-trifluoromethylphenyl)acetic acid 

Relevant academic research and scientific papers

Semirational Design of Fluoroacetate Dehalogenase RPA1163 for Kinetic Resolution of α-Fluorocarboxylic Acids on a Gram Scale

Here the synthetic utility of fluoroacetate dehalogenase RPA1163 is explored for the production of enantiomerically pure (R)-α-fluorocarboxylic acids and (R)-α-hydroxylcarboxylic acids via kinetic resolution of racemic α-fluorocarboxylic acids. While wild-type (WT) RPA1163 shows high thermostability and fairly wide substrate scope, many interesting yet poorly or moderately accepted substrates exist. In order to solve this problem and to develop upscaled production, in silico calculations and semirational mutagenesis were employed. Residue W185 was engineered to alanine, serine, threonine, or asparagine. The two best mutants, W185N and W185T, showed significantly improved performance in the reactions of these substrates, while in silico calculations shed light on the origin of these improvements. Finally, 10 α-fluorocarboxylic acids and 10 α-hydroxycarboxylic acids were prepared on a gram scale via kinetic resolution enabled by WT, W185T, or W185N. This work expands the biocatalytic toolbox and allows a deep insight into the fluoroacetate dehalogenase catalyzed C-F cleavage mechanism.

Highly Efficient Deracemization of Racemic 2-Hydroxy Acids in a Three-Enzyme Co-Expression System Using a Novel Ketoacid Reductase

Enantiopure 2-hydroxy acids (2-HAs) are important intermediates for the synthesis of pharmaceuticals and fine chemicals. Deracemization of racemic 2-HAs into the corresponding single enantiomers represents an economical and highly efficient approach for synthesizing chiral 2-HAs in industry. In this work, a novel ketoacid reductase from Leuconostoc lactis (LlKAR) with higher activity and substrate tolerance towards aromatic α-ketoacids was discovered by genome mining, and then its enzymatic properties were characterized. Accordingly, an engineered Escherichia coli (HADH-LlKAR-GDH) co-expressing 2-hydroxyacid dehydrogenase, LlKAR, and glucose dehydrogenase was constructed for efficient deracemization of racemic 2-HAs. Most of the racemic 2-HAs were deracemized to their (R)-isomers at high yields and enantiomeric purity. In the case of racemic 2-chloromandelic acid, as much as 300 mM of substrate was completely transformed into the optically pure (R)-2-chloromandelic acid (> 99% enantiomeric excess) with a high productivity of 83.8 g L?1 day?1 without addition of exogenous cofactor, which make this novel whole-cell biocatalyst more promising and competitive in practical application.

One-pot, single-step deracemization of 2-hydroxyacids by tandem biocatalytic oxidation and reduction

A facile and efficient one-pot, single-step method for deracemizing a broad range of 2-hydroxyacids to (R)-2-hydroxyacids was established by combination of resting cells of an (S)-hydroxyacid dehydrogenase-producing microorganism and an (R)-ketoacid reductase-producing microorganism.

Robust enzymatic resolution of 3-fluoromandelic acid with lipase PS supported on celite

The resolution of different mandelic acids using the lipase PS Amano SD enzyme is described. By supporting the lyophilized enzyme over Celite, both the activity and the stability of lipase PS in organic media were significantly improved, enabling the robust resolution scale-up of 3-fluoromandelic acid. The methodology was extended to produce a range of optically pure (R)-mandelic acids, avoiding tedious extractions or chromatography.

Hydrogen-bonding sheets in crystals for chirality recognition: synthesis and application of (2S,3S)-2,3-dihydroxy- and (2S,3S)-2,3-dibenzyloxy-1,4-bis(hydroxyamino)butanes

Two enantiopure bis(hydroxyamino) compounds were successfully prepared from dialkyl tartrate by a chiral-pool method and applied as basic resolving agents in the enantioseparation of 2-arylpropanoic acids and arylglycolic acids. (2S,3S)-2,3-Dihydroxy-1,4-bis(hydroxyamino)butane (2S,3S)-1a could moderately recognize the chirality of the 2-arylpropanoic acids, while (2S,3S)-2,3-dibenzyloxy-1,4-bis(hydroxyamino)butane (2S,3S)-1b could not due to the low crystallinity of both the corresponding diastereomeric salts. On the other hand, (2S,3S)-1b showed a similar chirality-recognition ability for the arylglycolic acids. The ability of (2S,3S)-1b was different from those generally observed for widely used primary amine-type resolving agents with regard to the relationship between the resolution efficiency and the similarity in the relative molecular length of a resolving agent and a target racemate. The X-ray crystallographic analyses of the less-soluble diastereomeric salts revealed that in the salts (2S,3S)-1a formed a supramolecular sheet, of which the distance was variable to make the resultant dissymmetric space fit to the shape of the target acids, and that (2S,3S)-1b was constructed from a robust supramolecular sheet, consisting of hydrogen-bonding 21 columns, with the participation of the hydroxy group of the arylglycolic acids. These X-ray crystallographic analyses also suggested that for the formation of a supramolecular sheet, the coexistence of two hydroxyamino groups is essential.

Semisynthetic cephalosporins. Synthesis and structure activity relationships of 7 mandelamido 3 cephem 4 carboxylic acids

The synthesis, microbiological profile, and in vivo effectiveness in laboratory animals of a broad spectrum cephalosporin, 7(R) mandelamidocephalosporanic acid (1), are described. A number of derivatives and analogs of 1 were prepared and their structure activity relationships are discussed.