544429-08-5Relevant academic research and scientific papers
Tertiary Amine Promoted Asymmetric Aldol Reaction of Aldehydes
Gut, Bartosz,Mlynarski, Jacek
, p. 5075 - 5078 (2015/08/18)
The direct asymmetric self-aldol reactions of various α-oxyaldehydes catalyzed by tertiary amines have been demonstrated. By using 10 mol-% of quinine catalyst, dimerization products have been prepared in high yields, with good anti-diastereocontrol, and up to 80% ee. The presented enolate-mediated synthesis of protected tetrose sugars has never been accomplished before by chiral tertiary amine organocatalysts.
Amino acid catalyzed neogenesis of carbohydrates: A plausible ancient transformation
Cordova, Armando,Ibrahem, Ismail,Casas, Jesus,Sunden, Henrik,Engqvist, Magnus,Reyes, Efraim
, p. 4772 - 4784 (2007/10/03)
Hexose sugars play a fundamental role in vital biochemical processes and their biosynthesis is achieved through enzyme-catalyzed pathways. Herein we disclose the ability of amino acids to catalyze the asymmetric neogenesis of carbohydrates by sequential cross-aldol reactions. The amino acids mediate the asymmetric de novo synthesis of natural L- and D-hexoses and their analogues with excellent stereoselectivity in organic solvents. In some cases, the four new stereocenters are assembled with almost absolute stereocontrol. The unique feature of these results is that, when an amino acid is employed as the catalyst, a single reaction sequence can convert a protected glycol aldehyde into a hexose in one step. For example, proline and its derivatives catalyze the asymmetric neogenesis of allose with > 99% ee in one chemical manipulation. Furthermore, all amino acids tested catalyzed the asymmetric formation of natural sugars under prebiotic conditions, with alanine being the smallest catalyst. The inherent simplicity of this catalytic process suggests that a catalytic prebiotic "gluconeogenesis" may occur, in which amino acids transfer their stereochemical information to sugars. In addition, the amino acid catalyzed stereoselective sequential cross-aldol reactions were performed as a two-step procedure with different aldehydes as acceptors and nucleophiles. The employment of two different amino acids as catalysts for the iterative direct aldol reactions enabled the asymmetric synthesis of deoxysugars with > 99% ee. In addition, the direct amino acid catalyzed C2+C 2+C2 methodology is a new entry for the short, highly enantioselective de novo synthesis of carbohydrate derivatives, isotope-labeled sugars, and polyketide natural products. The one-pot asymmetric de novo syntheses of deoxy and polyketide carbohydrates involved a novel dynamic kinetic asymmetric transformation (DYKAT) mediated by an amino acid.
Synthesis of enantiomerically pure alkylated D-erythritols and D-threitols from D-xylose-structural influences on their mesophasic behavior
Bachir-Lesage,Gode,Goethals,Villa,Martin, Patrick
, p. 35 - 46 (2007/10/03)
1-O-Alkyl and 2-O-alkyl-D-threitol enantiomers were derived from 5-O-alkyl and 5-O-benzyl-1,2-O-isopropylidene-α-D-xylofuranoses. The analogous erythritol derivatives were also obtained from the same precursors via analogous D-ribose monoacetals. Mesophas
Cyclic phosphonomethylphosphinates: A new type of phosphorus-containing sugars
Bisseret, Philippe,Boiteau, Jean-Guy,Eustache, Jacques
, p. 2351 - 2354 (2007/10/03)
The first synthesis of arabino-configured cyclic phosphonomethylphosphinates is described. The key step is the condensation of the triethylester of H-phosphinylphosphonate 10 on an hydroxyaldehyde 11 derived from a D-arabinal derivative followed by a cyclization induced under acetylation conditions.
