mannich-bases has been researched along with 4--hydroxychalcone* in 1 studies
1 other study(ies) available for mannich-bases and 4--hydroxychalcone
| Article | Year |
|---|---|
Reagent-induced asymmetric induction in addition reaction of reduced glutathione onto bis-Mannich chalcones.
The stereochemistry of non-enzyme catalyzed nucleophilic addition of GSH to 4'-hydroxychalcone 1 and its bis-Mannich derivative 2 was investigated at different pH values (pH 3.2, 6.1, 7.4, and 8.0). The stereochemical outcome of the reactions was evaluated by HPLC-UV-Vis method. Under strongly acidic conditions (pH 3.2), an unexpected diastereoselective addition of GSH onto the bis-Mannich derivative 2 was observed. Such a selectivity could not be observed in the similar reaction of 2 with N-acetylcysteine. The observed stereoselectivity can be rationalized by ion-pair formation between the protonated Mannich nitrogens and the deprotonated GSH(glutamate)-carboxylate. To the best of our knowledge, this is the first example of reagent-induced asymmetric induction in Michael-type additions of thiols. Topics: Acetylcysteine; Chalcones; Chromatography, High Pressure Liquid; Glutathione; Hydrogen-Ion Concentration; Mannich Bases; Stereoisomerism | 2018 |