- Design, synthesis and cytotoxic activity of certain novel chalcone analogous compounds
-
A series of chalcone analogous compounds were designed and synthesized. Replacing/substituting the enone or ethylenic bridge of the parent chalcone with rigid heterocyclic moieties or substituted aromatic amines gave nineteen target compounds. Their cytot
- El-Meligie,Taher, Azza T.,Kamal, Aliaa M.,Youssef
-
-
- Electrochemically induced ring-opening/friedel-crafts arylation of chalcone epoxides catalyzed by a triarylimidazole redox mediator
-
The indirect anodic oxidation of chalcone epoxides in the presence of electron-rich heteroarenes mediated by a triarylimidazole (Med) was investigated by cyclic voltammetry (CV) and controlled potential electrolysis. The CV results indicate that a homogeneous electron transfer between Med?+ and chalcone epoxides is facilitated by an electron-rich heteroarene that serves as an arylation reagent. The preparative scale electrolysis generated epoxide-ring-opened/Friedel-Crafts arylation products in moderate to good yields. The fact that only a catalytic amount of charge was required suggests that Med?+ initiates a chain reaction. In addition, overoxidation of the products is avoided even though their oxidation potential is less than that of the starting chalcone epoxides.
- Lu, Nan-Ning,Zhang, Ni-Tao,Zeng, Cheng-Chu,Hu, Li-Ming,Yoo, Seung Joon,Little, R. Daniel
-
p. 781 - 789
(2015/02/19)
-
- Practical approach for preparation of unsymmetric benzils from β-ketoaldehydes
-
An efficient and practical method for the synthesis of unsymmetric benzils from readily available β-ketoaldehydes has been developed. Various unsymmetric 1,2-diaryldiketones bearing functional groups have been obtained in good to excellent yields under mild reaction conditions. A plausible mechanism was proposed, and α,α-dichloroketone was considered as the key intermediate. The generation of α,α-dichloroketones from β-ketoaldehydes may undergo the following steps: (1) oxidation by sodium hypochlorite, (2) decarboxylation, and (3) chlorination by Cl2 generated from sodium hypochlorite.
- Ruan, Libo,Shi, Min,Li, Nian,Ding, Xu,Yang, Fan,Tang, Jie
-
supporting information
p. 733 - 735
(2014/03/21)
-
- Synthesis of 3,5-diphenyl-1H-pyrazoles
-
An efficient and convenient synthesis of 3,5-diphenyl-1N-pyrazoles from chalcones by the action of hydrazine hydrate on chalcone-epoxide followed by simultaneous dehydration is reported. Copyright Taylor & Francis, Inc.
- Bhat,Puri,Qurishi,Dhar,Qazi
-
p. 1135 - 1142
(2007/10/03)
-
- Solvent Microstructure Effect on Reaction Stereochemistry; Ring Opening of Chalcone Oxides
-
The stereochemistry and kinetics of acid-catalysed ring-opening reactions of epoxides are reported.Predominant inversion is found in the usual hydroxylic solvents.As the nucleophilicity of the solvent diminishes and acidity increases, the stereochemistry changes to predominant retention.Electron-donating substituents also tend to favour retention.In mixed solvents, the solvent microstructure is altered, leading to net retention for nucleophiles such as methanol.The exception is dioxane-methanol, which gives enhanced inversion.Molecular mechanics calculations indicate an electrostatic preference for the retention route, but a steric preference for inversion.The activation parameters indicate a negative entropy for both inversion and retention paths.Possible reasons are discussed for the entropy of the retention route being in the range normally found for A2 reactions.
- Durham, Dana,Kingsbury, Charles A.
-
p. 923 - 930
(2007/10/02)
-