147383-72-0Relevant articles and documents
Chemoenzymatic Production of Enantiocomplementary 2-Substituted 3-Hydroxycarboxylic Acids from l-α-Amino Acids
Pickl, Mathias,Marín-Valls, Roser,Joglar, Jesús,Bujons, Jordi,Clapés, Pere
, p. 2866 - 2876 (2021/04/14)
A two-enzyme cascade reaction plus in situ oxidative decarboxylation for the transformation of readily available canonical and non-canonical l-α-amino acids into 2-substituted 3-hydroxycarboxylic acid derivatives is described. The biocatalytic cascade consisted of an oxidative deamination of l-α-amino acids by an l-α-amino acid deaminase from Cosenzaea myxofaciens, rendering 2-oxoacid intermediates, with an ensuing aldol addition reaction to formaldehyde, catalyzed by metal-dependent (R)- or (S)-selective carboligases namely 2-oxo-3-deoxy-l-rhamnonate aldolase (YfaU) and ketopantoate hydroxymethyltransferase (KPHMT), respectively, furnishing 3-substituted 4-hydroxy-2-oxoacids. The overall substrate conversion was optimized by balancing biocatalyst loading and amino acid and formaldehyde concentrations, yielding 36–98% aldol adduct formation and 91–98% ee for each enantiomer. Subsequent in situ follow-up chemistry via hydrogen peroxide-driven oxidative decarboxylation afforded the corresponding 2-substituted 3-hydroxycarboxylic acid derivatives. (Figure presented.).
The highly enantioselective phase-transfer catalytic mono-alkylation of malonamic esters
Kim, Mi-Hyun,Choi, Sea-Hoon,Lee, Yeon-Ju,Lee, Jihye,Nahm, Keepyung,Jeong, Byeong-Seon,Park, Hyeung-Geun,Jew, Sang-Sup
supporting information; experimental part, p. 782 - 784 (2009/07/10)
The phase-transfer catalytic alkylation of N,N-dialkylmalonamic tert-butyl esters in the presence of 1 mol% of (S,S)-3,4,5-trifluorophenyl-NAS bromide afforded highly enantioselective (S)-mono-α-alkylated products (up to 96% ee), which could be readily converted into versatile chiral building blocks without loss of chirality. The Royal Society of Chemistry.
Cleavage of β-lactone ring by serine protease. Mechanistic implications
Kim, Dong H.,Park, Jeong-il,Chung, Sang J.,Park, Jung Dae,Park, No-Kyung,Han, Jong Hoon
, p. 2553 - 2560 (2007/10/03)
Both enantiomers of 3-benzyl-2-oxetanone (1) were found to be slowly hydrolyzed substrates of α-chymotrypsin having kcat values of 0.134±0.008 and 0.105±0.004 min-1 for (R)-1 and (S)-1, respectively, revealing that α-CT is virtually unable to differentiate the enantiomers in the hydrolysis of 1. The initial step to form the acyl-enzyme intermediate by the attack of Ser-195 hydroxyl on the β-lactone ring at the 2-position in the hydrolysis reaction may not be enzymatically driven, but the relief of high ring strain energy of β-lactone may constitute a major driving force. The deacylation step is also attenuated, which is possibly due to the hydrogen bond that would be formed between the imidazole nitrogen of His-57 and the hydroxyl group generated during the acylation in the case of (R)-1, but in the α-CT catalyzed hydrolysis of (S)-1 the imidazole nitrogen may form a hydrogen bond with the ester carbonyl oxygen.
