852402-28-9Relevant articles and documents
Diastereoselective conjugate addition/cyclization/bromination: Access to four stereocenters in a single step
Liao, Junzhuo,Drueckhammer, Dale G.
, p. 1776 - 1778 (2018)
A stereoselective tandem conjugate addition reaction with a chiral amine-derived nucleophile is reported in which the enolate intermediate is quenched with 1,2-dibromotetrachloroethane as a mild brominating reagent. X-ray analysis of a subsequent derivative was used to prove the configuration at each of the four newly formed stereocenters. The resulting α-bromoester underwent selective transesterification catalyzed by mild base to allow selective manipulation of the two ester groups of the product.
Enantioselective desymmetrization of prochiral cyclohexanones by organocatalytic intramolecular michael additions to α,β-unsaturated esters
Gammack Yamagata, Adam D.,Datta, Swarup,Jackson, Kelvin E.,Stegbauer, Linus,Paton, Robert S.,Dixon, Darren J.
supporting information, p. 4899 - 4903 (2015/04/14)
A new catalytic asymmetric desymmetrization reaction for the synthesis of enantioenriched derivatives of 2-azabicyclo[3.3.1]nonane, a key motif common to many alkaloids, has been developed. Employing a cyclohexanediamine-derived primary amine organocatalyst, a range of prochiral cyclohexanone derivatives possessing an α,β-unsaturated ester moiety linked to the 4-position afforded the bicyclic products, which possess three stereogenic centers, as single diastereoisomers in high enantioselectivity (83-99 % ee) and in good yields (60-90 %). Calculations revealed that stepwise C-C bond formation and proton transfer via a chair-shaped transition state dictate the exclusive endo selectivity and enabled the development of a highly enantioselective primary amine catalyst.
Copper-catalyzed asymmetric allylic alkylation of halocrotonates: Efficient synthesis of versatile chiral multifunctional building blocks
Den Hartog, Tim,Macia, Beatriz,Minnaard, Adriaan J.,Feringa, Ben L.
experimental part, p. 999 - 1013 (2010/08/07)
The highly enantioselective synthesis of amethyl-substituted esters is reported in up to 90% yield and up to 99% ee using copper-TaniaPhos as chiral catalyst. The transformation proved scalable to at least 6.6 mmol (1.7 g scale). The products of this transformation have been further elaborated to multifunctional building blocks with a single (branched esters and acids) or multiple stereogenic centers (vicinal dimethyl esters, as well as, hydroxy- or iodosubstituted lactones).
Syntheses, Structures, and Enzymatic Evaluations of Conformationally Constrained, Analogue Inhibitors of Carnitine Acetyltransferase: (2R,6R)-, (2S,6S)-, (2R,6S)-, and (2S,6R)-6-(Carboxylatomethyl)-2-(hydroxymethyl)-2,4,4-trimethylmorpholinium
Sun, Guobin,Savle, Prashant S.,Gandour, Richard D.,a'Bhaird, Noirin Nic,Ramsay, Rona R.,Fronczek, Frank R.
, p. 6688 - 6695 (2007/10/03)
The syntheses and structures of the four stereoisomers of 6-(carboxylatomethyl)-2-(hydroxymethyl)-2,4,4-trimethylmorpholinium, 1, are described.The key step in the synthetic strategy involves an intramolecular Michael addition reaction.Condensation of nonracemic 3-(methylamino)-2-methylpropane-1,2-diol, 3, with methyl 4-bromo-2-butenoate followed by intramolecular Michael addition gives a mixture of two diastereomers of methyl 2-acetate, 5.The diastereomeric ratio of the products in this reaction changes from 6:1 to 1:1 with a change in solvent from diethyl ether:methanol (35:1, v:v) to methanol.The structures and absolute configurations of 1 were determined by single crystal X-ray analyses.In crystals and solution, the morpholinium rings adopt a chair conformation with carboxylatomethyl occupying an equatorial position.All four stereoisomers inhibit pigeon breast carnitine acetyltransferase (CAT).Of this series, (2S,6R)-1 binds to CAT most strongly with a Ki of 190 +/- 20 μM and an IC 50 of 0.42 mM.The enzymatic assays of 1 confirm that CAT recognizes both configurations at C2 and C6 in the analogues.CAT has a different conformation when it binds carnitine or acetylcarnitine than when it binds 1.This latter conformation may resemble that when CAT catalyzes acetyl transfer.
Synthesis and Structure-Activity Relationships of Naftifine-Related Allylamine Antimycotics
Stuetz, Anton,Georgopoulos, Apostolos,Granitzer, Waltraud,Petranyi, Gabor,Berney, Daniel
, p. 112 - 125 (2007/10/02)
Naftifine (1) is the first representative of the new antifungal allylamine derivatives.Its biological activity is strictly bound to specific structural requirements that are unrelated to those of known antifungals.A tertiary allylamine function seems to be a prerequisite for activity against fungi.By systematic variation of the individual structural elements in 1, detailed structure-activity relationships are defined in which the phenyl ring is the structural feature permitting the widest variations.Versatile synthetic routes to allylamine derivatives and comparative biological data are presented.
