84959-65-9Relevant academic research and scientific papers
Synthesis and evaluation of 1,4-naphthoquinone ether derivatives as SmTGR inhibitors and new anti-schistosomal drugs
Johann, Laure,Belorgey, Didier,Huang, Hsin-Hung,Day, Latasha,Chessé, Matthieu,Becker, Katja,Williams, David L.,Davioud-Charvet, Elisabeth
, p. 3199 - 3217 (2015/08/24)
Investigations regarding the chemistry and mechanism of action of 2-methyl-1,4-naphthoquinone (or menadione) derivatives revealed 3-phenoxymethyl menadiones as a novel anti-schistosomal chemical series. These newly synthesized compounds (1-7) and their di
Chemical consequences of fluorine substitution. Part 4. Diels-Alder reactions of fluorinated p-benzoquinones with Dane's diene. Synthesis of fluorinated D-homosteroids
Essers, Michael,Haufe, Guenter
, p. 2719 - 2728 (2007/10/03)
Four fluorinated p-benzoquinones (2) have been reacted with Dane's diene (1) in Diels-Alder reactions and the formed fluorinated D-homosteroids were characterized. The number of products, their stereochemistry and stability depends on the fluorine substitution pattern of the corresponding fluorinated p-benzoquinones. If the p-benzoquinone (2) contains an unfluorinated double bond, this bond reacts faster with diene 1 yielding endo-products selectively. In contrast, [4+2]cycloadditions with 2,6-difluoro (2c) and 2,3,5,6-tetrafluorobenzoquinone (2d) gave the products with exo-orientation of the carbonyl part preferably.
Stereopopulation Control. 7. Rate Enhancement in the Lactonization of 3-(o-Hydroxyphenyl)propionic Acids: Dependence on the Size of Aromatic Ring Substituents
King, Michael M.,Cohen, Louis A.
, p. 2752 - 2760 (2007/10/02)
A series of 4,4-dimethyl-6-hydroxyhydrocoumarins was synthesized with various combinations of methyl and halogen groups at C-5 and C-7.The 5,7-difluoro compound was obtained by condensation of difluorohydroquinone with dimethylacrylic ester.Controlled chlorination of the parent phenolic lactone provided the 5- and 7-chloro isomers, in addition to the 5,7-dichloro product.On the other hand, bromination gave both the 5,7-dibromo and 7-bromo products, without trace of the 5-bromo isomer; finally, iodination gave only the 7-iodo product.These compounds were converted into 6-mesylates as protection against air oxidation of the hydroquinone system in alkaline media.The lactones were hydrolyzed in aqueous base, and the kinetics of relactonization were measured at 30 deg C over a wide pH range.As previously shown for similar systems, lactonization is subject to both general acid and general base catalysis.After adjustment of the rate constants (k') for the electronic effects of ring substituents, the residual rate constants (k'') were found to increase with the size of the C-5 substituent, the value for bromine being 4800 times that for hydrogen.A plot of log k''cat vs. the van der Waals radius of the substituent is linear, demonstrating the existence of a free energy continuum in the relationship between k'' for lactonization and the conformational mobility of the three-carbon side chain.
