76641-72-0Relevant academic research and scientific papers
Bioreduction of α-Acetoxymethyl Enones: Proposal for an SN2′ Mechanism Catalyzed by Enereductase
Paula, Bruno R. S.,Zampieri, Davila,Rodrigues, J. Augusto R.,Moran, Paulo J. S.
, p. 3555 - 3571 (2016/11/25)
(Z)-3-Acetoxymethyl-4-R-3-buten-2-ones (R=aryl, alkyl) and (Z)-3-methyl-4-R-3-buten-2-ones (R=aryl) were synthesized and submitted to reduction by the yeast Saccharomyces cerevisiae producing the (R)- and (S)-4-R-3-methybutan-2-ones, respectively. This stereochemistry control strategy was applied in the syntheses of (R)- and (S)-Tropional with moderate to high enantiomeric excesses. Other (Z)-3-acyloxymethyl-4-phenyl-3-buten-2-ones showed similar behavior to the (Z)-3-acetoxymethyl counterpart, and the acylated Morita–Baylis–Hillman adduct 1-acetoxy-2-methylene-1-phenylbutan-3-one produced a mixture of products, with and without the acetoxy group, via three different reaction pathways. In addition to experiments employing whole cells, those in which isolated enereductases were used suggested that the main pathway through which the loss of the acetoxy group occurs during the biocatalytic cascade is an SN2′-type reaction, rather than formal hydrogen addition followed by acetic acid elimination. Finally, related ethyl enones were reduced enantioselectively by the yeast Candida albicans, producing both (R)- and (S)-reduction products, depending on the presence of the acetoxy group in the starting material. (Figure presented.).
Redox-Annulation of Cyclic Amines and β-Ketoaldehydes
Chen, Weijie,Seidel, Daniel
supporting information, p. 1024 - 1027 (2016/03/15)
Benzo[a]quinolizine-2-one derivatives are readily assembled from 1,2,3,4-tetrahydroisoquinoline and β-ketoaldehydes by means of a new intramolecular redox-Mannich process. These reactions are promoted by simple acetic acid and are thought to involve azomethine ylides as reactive intermediates.
Efficient synthesis of α-(hydroxymethyl) ketones not available through aldol-type processes
Hitchcock,Perron,Martin,Albizati
, p. 1059 - 1061 (2007/10/02)
An efficient synthesis of α-(hydroxymethyl) ketones from β-keto esters has been developed, which is experimentally simple, amenable to large scale production and provides products of high purity without resort to chromatography in most cases. The method is a useful alternative and complement to condensation processes.
Chemistry of aldolate dianions. Effects of β-heteroatom substituents on ketone enolization
Van Martin,Murray, Desmond H.,Pratt, Norman E.,Zhao, Yun-Bo,Albizati, Kim F.
, p. 6965 - 6978 (2007/10/02)
β-Hydroxy ketones can be doubly deprotonated with >2 equiv of an amide base at low temperature providing both proximal or distal aldolate dianions in good to excellent yield. A variety of substitutionally biased β-hydroxy ketones give exclusively distal dianions. If the distal site is blocked, proximal dianions are formed in good yield; however, Chromatographic separation of the silylated products leads to decreased yields. Comparative enolization studies of 4-hydroxy-2-butanone, l-hydroxy-3-pentanone, and hydroxyl-substituted derivatives reveal a kinetic factor favoring proximal deprotonation of β-OTMS and β-alkoxy ketones. However, there is a thermodynamic factor favoring distal dianions that becomes significant as solutions of the dianions are warmed. Thermal stability studies indicate good room temperature stability of the dianions toward elimination and retroaldolization processes; control studies in this area also support the presence of a dianionic species. Precedent suggests that the dianions exist as internally chelated species, and we speculate that ion triplets containing bridging lithiums are good candidates for the structure of both proximal and distal dianion species. The distal dianions undergo clean reaction with aldehydes and acyl cyanides leading to β,β′-dihydroxy ketones and β-hydroxy-β′-oxo ketones, respectively.
Specific enzyme inhibitors in vitamin biosynthesis. Part 3. The synthesis and inhibitory properties of some substrates and transition state analogues of riboflavin synthase
Al-Hassan, Saieba S.,Kulick, Russell J.,Livingstone, Daniel B.,Suckling, Colin J.,Wood, Hamish C. S.,Wrigglesworth, Roger,Ferone, Robert
, p. 2645 - 2656 (2007/10/02)
Syntheses of potential inhibitors of riboflavin synthase are described. The tolerance of the enzyme to bulky substituents was investigated by the synthesis of substrate analogues which included lumazines and pyrido[2,3-d]-pyrimidines prepared by condensation of α-diketones and β-keto-aldehydes respectively with appropriate amino-substituted uracils. Potential transition-state analogues, including 7-oxolumazines, 7-oxopyrido[2,3-d] pyrimidines, and 6,7-dioxolumazines were also prepared by similar condensations using α-keto-acid derivatives, dimethyl acetylenedicarboxylate, and oxalate derivatives. Two possible dual affinity inhibitors were also prepared. The potential inhibitors were tested using riboflavin synthase from yeast or from E. coli, and their effectiveness is discussed in relation to the bulk and electronic character of the substituents.
