Search results for "medicinal"
showing 10 items of 2966 documents
ChemInform Abstract: First Reactions of Dialkoxycarbenium Tetrafluoroborates with Pyrroles, 5H-Dibenz(b,f)azepines, and Electron-Rich Arenes.
1990
Pyrrole (2a) and 2,5-dimethylpyrrole (2b) react with the dialkoxycarbenium tetrafluoroborates 1a-1c under kinetic control to yield the corresponding acylpyrrole derivatives. 5H-Dibenz[b,f]azepine (9a) and the 10,11-dihydro derivative 9b react only with the most electrophilic of the series of electrophiles tested, namely, diethoxycarbenium tetrafluoroborate (1a), to furnish the corresponding formyl derivatives. Similarly, in arene chemistry, the highly electron-rich N,N-dimethylaniline (13a) and 1,3,5-trimethoxybenzene (13b) are formylated by reaction with 1a.
Back Cover: A Regio- and Diastereoselective Anodic Aryl-Aryl Coupling in the Biomimetic Total Synthesis of (−)-Thebaine (Angew. Chem. Int. Ed. 34/201…
2018
H2-Antihistaminika, 6. Mitt. Synthese und Wirkung N-substituierter 4-[(2-Amino-ethylmercapto)-methyl]-imidazole
1980
Es wurden die N-substituierten 4-[(2-Amino-ethylmercapto)-methyl]-imidazole 2 und 3 dargestellt und auf histaminartige Wirkung untersucht. Die Thioharnstoff- und Cyanoguanidin-Derivate von 3b zeigten keine H2-antihistaminische Wirksamkeit. H2-Antihistaminics, VI: Synthesis and Activity of N-Substituted 4-[(2-Aminoethylmercapto)methyl]imidazoles The N-substituted 4-[(2-aminoethylmercapto)methyl]imidazoles 2 and 3 were prepared and tested for their histamine-like activity. The thiourea and cyanoguanidine derivatives of 3b showed no H2-antihistaminic activity.
ChemInform Abstract: E,Z-Stereodivergent Synthesis of N-Tosyl α,β-Dehydroamino Esters via a Mukaiyama-Michael Addition
2016
The stereodivergent synthesis of N-tosyl α,β-dehydroamino esters via a Mukaiyama–Michael addition is reported. The reaction of silylketene acetals with N-tosylimines derived from β,γ-unsaturated α-keto esters in dichloromethane provided the corresponding (Z)-α,β-dehydroamino esters while the (E)-isomers were obtained when the reaction was carried out in the presence of 10 mol% copper(II) triflate.
Anticancer Activity of Salvia miltiorrhiza and Its Secondary Metabolites
2017
Salvia miltiorrhiza Bunge (danshen) is a well-known traditional Chinese medicinal herb. The root part of the plant contains most of the bioactive ingredients, which mainly belong to two groups of compounds: hydrophilic phenolic acids and hydrophobic tanshinones. These bioactive compounds refer to as secondary metabolites and exert multiple therapeutic activities, such as anti-oxidative stress, anti-neurodegenerative, anti-inflammatory, and anti-hypertensive effects without showing serious side effects. Besides these pharmacological activities, anticancer effects have also attracted scientific attention. This review will provide an updated summary of the anticancer effects and the proposed m…
ChemInform Abstract: Highly Enantioselective Copper(I)-Catalyzed Conjugate Addition of Terminal Alkynes to 1,1-Difluoro-1-(phenylsulfonyl)-3-en-2-one…
2014
A highly enantioselective copper-catalyzed conjugate alkynylation of monoactivated enones, namely 1,1-difluoro-1-(phenylsulfonyl)-3-en-2-ones, is described. The reaction products are obtained with good yields and excellent enantioselectivities (from 92 to 99% ee). The β-alkynylated difluoro(phenylsulfonyl) ketones can be converted into the corresponding β-alkynylated difluoro- and trifluoromethyl ketones, esters and amides. This is the first example on the use of 1,1-difluoro-1-(phenylsulfonyl)-3-en-2-ones as substrates in an enantioselective reaction, which have been shown to be new ester/amide surrogates.
Understanding the Influence of the Trifluoromethyl Group on the Selectivities of the [3+2] Cycloadditions of Thiocarbonyl S ‐methanides with α,β‐Unsa…
2020
Intramolecular Cycloaddition Azomethine Ylides and α-(Trifluoromethyl)styrenes as Dipolarophiles
2019
A new strategy for the synthesis of highly functionalised fluorinated compounds by reaction of lithium dianions of carboxylic acids with perfluoroket…
2005
The reaction of perfluoroketene dithioacetal with lithium dienediolates of carboxylic acids proceeds at the ω position probably through an addition to the π system followed by elimination of the vinylic fluoride. The preparative value of this reaction depends strongly on the reaction and work-up conditions. The overall process lead to highly functionalised synthons containing a trifluoromethyl group.
ChemInform Abstract: Catalytic Enantioselective Conjugate Alkynylation of β-Aryl-β-trifluoromethyl Enones Constructing Propargylic All-Carbon Quatern…
2016
The enantioselective conjugate alkynylation of β-aryl-β-trifluoromethyl enones has been carried out using terminal alkynes and diethylzinc in the presence of 3,3′-bis(perfluorophenyl)BINOL as the chiral ligand to give the corresponding ketones bearing a trifluoromethylated propargylic quaternary stereocenter with fair to good enantioselectivities. Enones bearing a bulky 2-naphthyl attached to the carbonyl group provided the best enantioselectivities. The synthetic applicability of the resulting products has been demonstrated with their iodocyclization to form 4H-pyrans.