10148-68-2Relevant academic research and scientific papers
Synthesis of γ-halogenated and long-chain β-hydroxy-α-amino acids and 2-amino-1,3-diols using threonine aldolases
Steinreiber, Johannes,Fesko, Kateryna,Mayer, Clemens,Reisinger, Christoph,Schürmann, Martin,Griengl, Herfried
, p. 8088 - 8093 (2007)
The l- and d-threonine aldolase catalyzed formation of γ-halogenated and long-chain l- and d-3-alkylserine-derivatives 1-12, respectively, was shown starting from glycine and halogenated C2- or C4-C12 aldehydes. lTA from Pseudomonas putida accepted all tested aldehydes with strongly varying diastereoselectivity (de up to 93%). Only aldehydes smaller than decanal were converted by dTA from Alcaligenes xylosoxidans with good selectivities (de up to 73%). Utilizing isobutanal enantio- and diastereopure d-syn-2-amino-3-hydroxy-4-methylpentanoic acid was obtained (ee>99%, de>95%), which was converted to the corresponding 2-amino-1,3-diol.
Enzymatic synthesis of β-hydroxy-α-amino acids based on recombinant D- and L-threonine aldolases
Kimura, Teiji,Vassilev, Vassil P.,Shen, Gwo-Jenn,Wong, Chi-Huey
, p. 11734 - 11742 (1997)
To exploit the enzymatic method for the synthesis of β-hydroxy-α-amino acids, the genes coding for the Escherichia coli L-threonine aldolase (LTA; EC 2.1.2.1) and Xanthomonus oryzae D-threonine aldolase (DTA) were cloned and overexpressed in E. coli through primer-directed polymerase chain reactions. The purified recombinant enzymes were studied with respect to kinetics, specificity, stability, additive requirement, temperature profile, and pH dependency. DTA requires magnesium ion as a cofactor, while LTA needs no metal ions. These enzymes work well in the presence of DMSO with concentration up to 40%, and DMSO-induced rate acceleration of LTA-catalyzed reaction was observed. Both enzymes use pyridoxal phosphate coenzyme to activate glycine to react with a wide range of aldehydes. LTA gave erythro-β-hydroxy-α-L-amino acids with aliphatic aldehydes and the threo isomer with aromatic aldehydes as kinetically controlled products. On the other hand, DTA formed threo-β-hydroxy-α-D-amino acids as kinetically controlled products with aliphatic and aromatic aldehydes but the diastereoselectivity was lower than that of LTA. Under optimal conditions, several β-hydroxy-α-amino acid derivatives (3-hydroxyleucines, γ-benzyloxythreonines, γ-benzyloxymethylthreonines, and poplyoxamic acids) have been stereoselectively synthesized on preparative scales using these enzymes. Also, the tandem use of DTA and phosphatases has made possible the synthesis and separation of D-allo-threonine phosphate and D-threonine.
ASYMMETRIC ALDOL REACTIONS USING BORON ENOLATES OF CHIRAL OXAZINONES, SYNTHESIS OF L-ALLO-THREONINE
Reno, Daniel S.,Lotz, Bruce T.,Miller, Marvin J.
, p. 827 - 830 (2007/10/02)
The boron enolate of oxazinone 1 was allowed to react with acetaldehyde, butanal, and 2-methylpropanal.The reaction proceeded stereoselectively, and in the reaction with acetaldehyde, the reaction afforded a precursor to L-allo-threonine.
