Results 41 to 50 of about 187,468 (290)
Heteroatom Chemistry, 2021 Tandem conjugate addition–alkylation reaction of various amines with α-bromo-α, β-unsaturated ketones resulted in near-quantitative conversions into the corresponding aziridines when the reaction was carried out in the presence of 10 mol% of phase ...
Alemayehu Mekonnen, Alemu Tesfaye
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The Cinchona Program (1940-1945) : science and imperialism in the exploitation of a medicinal plant [PDF]
, 2011 During World War II, the United States implemented programs to exploit hundreds of raw materials in Latin America, many of them botanical. This required the participation of the country's scientific community and marked the beginning of intervention in ...
Cuvi, Nicolás +1 more
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Malaria Journal, 2003 Background The 8-amino and 9-hydroxy substituents of antimalarial cinchona alkaloids have the erythro orientation while their inactive 9-epimers are threo.
Meyer David J +4 more
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Synthesis and Applications of Carbohydrate-Based Organocatalysts
Molecules, 2021 Organocatalysis is a very useful tool for the asymmetric synthesis of biologically or pharmacologically active compounds because it avoids the use of noxious metals, which are difficult to eliminate from the target products.
Elżbieta Wojaczyńska +4 more
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Beyond phylogeny: phytochemical diversity as a unique metric for biodiversity in the Gentianales. [PDF]
New PhytolSummary In contrast to phylogenetic diversity (PD), phytochemical diversity is not often utilised to measure biodiversity, although it forms an important aspect of biotic variation. The aim of this study was to explore phytochemical diversity across the flowering plant order Gentianales and the extent to which PD reliably represents phytochemical ...
Richard-Bollans A +3 more
europepmc +2 more sources
Organocatalytic Enantioselective Henry Reactions [PDF]
, 2011 This is an open access article distributed under the Creative Commons Attribution License.A large number of interesting organocatalytic enantioselective protocols have been explored and successfully applied in the last decade.
Herrera, Raquel P. +2 more
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Organocatalytic asymmetric addition of malonates to unsaturated 1,4-diketones
Beilstein Journal of Organic Chemistry, 2012 The organocatalytic Michael addition of malonates to symmetric unsaturated 1,4-diketones catalyzed by thiourea and squaramide derivatives with Cinchona alkaloids afforded the formation of a new C–C bond in high yields (up to 98%) and enantiomeric ...
Sergei Žari +7 more
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Design and evaluation of selective butyrylcholinesterase inhibitors based on Cinchona alkaloid scaffold. [PDF]
PLoS ONE, 2018 This paper describes the synthesis and anticholinesterase potency of Cinchona-based alkaloids; ten quaternary derivatives of cinchonines and their corresponding pseudo-enantiomeric cinchonidines. The quaternization of quinuclidine moiety of each compound
Anita Bosak +5 more
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Practical, highly stereoselective allyl- and crotylsilylation of aldehydes catalyzed by readily available Cinchona alkaloid amide [PDF]
, 2013 10.1039/c3sc50973gChemical Science483275 ...
Bai +68 more
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Beilstein Journal of Organic Chemistry, 2021 Cinchona alkaloid-derived organocatalysts are widely employed in various asymmetric transformations, yielding products with high enantiopurity. In this respect, a bifunctional quinine-derived sulfonamide organocatalyst was developed to catalyze the ...
Deniz Tözendemir, Cihangir Tanyeli
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