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Regioselectivity of glycosylation reactions of galactose acceptors: an experimental and theoretical study
(Beilstein-Institut, 2019-12)
Regioselective glycosylations allow planning simpler strategies for the synthesis of oligosaccharides, and thus reducing the need of using protecting groups. With the idea of gaining further understanding of such ...
A DFT analysis of the strain-induced regioselective[2+2]cycloaddition of benzyne possessing fused four-membered ring
(2005)
The regioselective [2+2] cycloaddition of a substituted benzyne possessing a fused four-membered ring to a ketene acetal has been theoretically studied. This cycloaddition presents a two-step mechanism that is initiated ...
The regioselective bromination of 4,4-dimethyl-5,8-dihydroxy-4H-naphthalen-1-one
(Marcel Dekker, Inc., 1998)
Methods for the regioselective bromination of the title naphthalenone are described, wich lead to isomeric hydroquinones 5 or 6..
Understanding reactivity and regioselectivity in Diels–Alder reactions of a sugar-derived dienophile bearing two competing EWGs. An experimental and computational study
(Elsevier, 2015-08)
The effect of an extra EWG in the reactivity and regioselectivity in Diels?Alder reactions of β-cyanolevoglucosenone and 4 different dienes was studied by a joint computational and experimental study. Conceptual DFT analysis ...
Regioselectivity of the glycosylation of N-dimethylmaleoyl-protected hexosamine acceptors. An experimental and DFT approach
(Royal Society of Chemistry, 2011-02-11)
Both anomers of the methyl glycoside of 6-O-benzyl-N-dimethylmaleoyl-D-allosamine (6 and 7) are glycosylated exclusively on O3 when reacting with the trichloroacetimidate of peracetylated α-D-galactopyranose (5). This ...
Theoretical insights into the regioselectivity of a Pictet-Spengler reaction: transition state structures leading to salsolinol and isosalsolinol
(Wiley, 2017)
The mechanism of the cyclization step of the Pictet-Spengler reaction between acetaldehyde and dopamine to give salsolinol and isosalsolinol was studied computationally, using density functional theory. The preferential ...
Looking at the big picture in activation strain model/energy decomposition analysis: The case of the: Ortho - Para regioselectivity rule in Diels-Alder reactions
(Royal Society of Chemistry, 2020-02)
The regioselectivity of the Diels-Alder reaction is predicted by the ortho-para rule which has been explained from FMO theory. Using DFT calculations, the activation-strain model and energy decomposition analysis we studied ...
Molecular design and structural optimization of nanocellulose-based films fabricated via regioselective functionalization for flexible electronics
(2022-07-15)
Nanocellulose backbones highly regioselectively substituted with thiophene and long fatty acid side chains were synthesized via a protecting group strategy. The presence of long-chain pendants balanced the torsional ...
Understanding the influence of Lewis acids in the regioselectivity of the Diels-Alder reactions of 2-methoxy-5-methyl-1,4-benzoquinone: A DFT study
(2009)
The mechanisms of the Diels-Alder (DA) reactions of 2-methoxy-5-methyl-1,4-benzoquinone 1 with 2-methyl-1,3-butadiene 2, in the absence and in the presence of LA catalysts, have been studied using the DFT method at the ...
Regioselective Incorporation of Backbone Constraints Compatible with Traditional Solid-Phase Peptide Synthesis
(American Chemical Society, 2012-12)
A protected aldehyde was attached via a twocarbon spacer to a peptide backbone amide nitrogen during a traditional Merrifield solid-phase synthesis. Acid-mediated unmasking of the aldehyde triggered the regioselective ...