51532-30-0Relevant academic research and scientific papers
One-pot multi-enzymatic synthesis of the four stereoisomers of 4-methylheptan-3-ol
Brenna, Elisabetta,Crotti, Michele,Gatti, Francesco G,Monti, Daniela,Parmeggiani, Fabio,Pugliese, Andrea
, (2017)
The use of pheromones in the integrated pest management of insects is currently considered a sustainable and environmentally benign alternative to hazardous insecticides. 4-Methylheptan-3-ol is an interesting example of an insect pheromone, because its stereoisomers are active towards different species. All four possible stereoisomers of this compound were prepared from 4-methylhept-4-en-3-one by a one-pot procedure in which the two stereogenic centres were created during two sequential reductions catalysed by an ene-reductase (ER) and an alcohol dehydrogenase (ADH), respectively.
Investigating: Saccharomyces cerevisiae alkene reductase OYE 3 by substrate profiling, X-ray crystallography and computational methods
Powell, Robert W.,Buteler, M. Pilar,Lenka, Sunidhi,Crotti, Michele,Santangelo, Sara,Burg, Matthew J.,Bruner, Steven,Brenna, Elisabetta,Roitberg, Adrian E.,Stewart, Jon D.
, p. 5003 - 5016 (2018/10/17)
Saccharomyces cerevisiae OYE 3 shares 80% sequence identity with the well-studied Saccharomyces pastorianus OYE 1; however, wild-type OYE 3 shows different stereoselectivities toward some alkene substrates. Site-saturation mutagenesis of Trp 116 in OYE 3 followed by substrate profiling showed that the mutations had relatively little effect, opposite to that observed previously for OYE 1. The X-ray crystal structures of unliganded and phenol-bound OYE 3 were solved to 1.8 and 1.9 ? resolution, respectively. Both structures were nearly identical to that of OYE 1, with only a single amino acid difference in the active site region (Ser 296 versus Phe 296, part of loop 6). Despite their essentially identical static X-ray structures, molecular dynamics (MD) simulations revealed that loop 6 conformations differed significantly in solution between OYE 3 and OYE 1. In OYE 3, loop 6 remained nearly as open as observed in the crystal structure; by contrast, loop 6 closed over the active site of OYE 1 by ca. 4 ?. Loop closure likely generates a greater number of active site protein contacts for substrate bound to OYE 1 as compared to OYE 3. These differences provide an explanation for the differing stereoselectivities of OYE 3 and OYE 1, despite their nearly identical X-ray crystal structures.
ASYMMETRIC ALPHA FUNCTIONALIZATION AND ALPHA, ALPHA BISFUNCTIONALIZATION OF ALDEHYDES AND KETONES
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Page/Page column 18-19, (2009/12/05)
The present invention relates, generally, to asymmetric α-functionalization and to asymmetric α,α-bisfunctionalization of ketones and aldehydes and, in particular, to chiral auxiliaries suitable for use in effecting such functionalizations and to methods
Synthesis and absolute configuration of (S)-(+)-chichimol ketone: the defensive secretion of walking stick Agathemera elegans
Espinoza-Moraga, Marlene,Cornejo-Morales, Roxana,Santos, Leonardo Silva
scheme or table, p. 1062 - 1064 (2009/09/30)
The first enantioselective synthesis of chichimol ketone (4-methyl-1-hepten-3-one) is described and the absolute configuration of the main semiochemical compound is determined as having an (S)-configuration. The synthesis features the use of a ruthenium c
Simple and efficient asymmetric α-alkylation and α,α- bisalkylation of acyclic ketones by using chiral N-amino cyclic carbamate hydrazones
Lim, Daniel,Coltart, Don M.
experimental part, p. 5207 - 5210 (2009/04/11)
(Chemical Equation Presented) Distinguishing left from right: In the title reactions, chiral N-amino cyclic carbamates (ACCs) substantially diminish the drawbacks associated with the use of chiral dialkyl hydrazines, yet provide excellent stereoselectivity and high yields. In addition, ACCs exhibit a unique directing effect that overrides the inherent selectivity of lithium diisopropylamide (LDA) and enables the asymmetric α,α-bisalkylation of ketones (see scheme).
Enantiomeric partitioning using fluorous biphase methodology for lipase-mediated (trans)esterifications
Beier, Petr,O'Hagan, David
, p. 1680 - 1681 (2007/10/03)
Lipase-catalysed (trans)esterification reactions in homogenous perfluorocarbon-hydrocarbon solvents enabled direct enantiomeric partitioning (up to 95% ee) of the products by liquid-liquid separation.
A Conceptually Different Approach to the Asymmetric Synthesis of α-Substituted Carbonyl Compounds
Maruoka, Keiji,Nakai, Shuichi,Sakurai, Minoru,Yamamoto, Hisashi
, p. 130 - 132 (2007/10/02)
A new approach has been demonstrated for the asymmetric synthesis of α-substituted carbonyl compounds.Thus, the key assymetric carbon-carbon bond formation is accomplished by the highly diastereoselective addition of organoaluminum reagents to the chiral α,β-unsaturated acetal derived from the α,β-unsaturated aldehyde and (R,R)-tartaric acid diamide to furnish the 1,4-adduct preferentially along with the 1,2-adduct as a minor product.Subsequent oxidation of the combined adducts with ozone or the system potassium permanganate/sodium periodate gives rise to the optically active α-substituted aldehyde, ketone, or carboxylic acid, respectively, with high enantioselectivities.The present method has been applied to the facile synthesis of an anti-inflammatory agent and the principal alarm pheromone of the leaf-cutting ant Atta texana in optically active forms.
ACYCLIC STEREOCONTROL VIA -WITTIG REARRANGEMENT WITH HIGH ENANTIO- AND ERYTHRO-SELECTIVITY AND ITS USE IN THE CHIRAL SYNTHESIS OF INSECT PHEROMONES
Sayo, Noboru,Azuma, Ken-ichi,Mikami, Koichi,Nakai, Takeshi
, p. 565 - 568 (2007/10/02)
Such an asymmetric -Wittig variant that is both highly enantio- and erythro-selective is described within the context of the chiral synthesis of the insect pheromones, (3S,4S)-4-methyl-3-heptanol and (S)-4-methyl-3-heptanone.
An Asymmetric Synthesis of Acyclic and Macrocyclic α-Alkyl Ketones. The Role of (E)- and (Z)-Lithioenamines
Meyers, A. I.,Williams, Donald R.,White, Steven,Erickson, Gary W.
, p. 3088 - 3093 (2007/10/02)
Metalation and alkylation of chiral imines derived from C10, C12, and C15 cyclic ketones gave, under kinetic metalation conditions, 2-alkylcycloalkanones of absolute configuration opposite to that formed from thermodynamic metalation.Thus, (S)-(-)-2-methylcyclododecanone is formed kinetically in 60percent ee, whereas (R)-(+)-methylcyclododecanone is reached in 80percent ee under thermodynamic conditions.In a similar fashion, acyclic ketones 20, via their chiral imines 17, are alkylated enantioselectively under both kinetic and thermodynamic modes.The kinetic metalation gives exclusively the (Z)-lithioenamines (19), while reflux of this lithio anion gives only the (E)-lithioenamine (19).Chiral α-substituted ketones are produced in 18-97percent ee.
