N-Benzylhydroxylamine Addition to β-Aryl Enoates. Enantioselective Synthesis of β-Aryl-β-amino Acid Precursors
摘要:
[GRAPHICS]Chiral Lewis acid catalyzed N-benzylhydroxylamine addition to pyrrolidinone-derived enoates afforded beta-aryl-beta-amino acid derivatives in high enantiomeric purity with moderate to very good chemical efficiency.
<i>N</i>-Acylation of Oxazolidinones via Aerobic Oxidative NHC Catalysis
作者:Linda Ta、Anton Axelsson、Henrik Sundén
DOI:10.1021/acs.joc.8b01723
日期:2018.10.5
synthetically useful oxazolidinones with aldehydes using aerobicoxidative NHC catalysis is reported. The reaction offers a broad scope of functionalized oxazolidinones in good to excellent yields. Careful choice of electron transfer mediators proved pivotal to achieve efficient aerobic N-acylation, which has previously proven difficult using NHC catalysis. The methodology allows a mild entry to acylated oxazolidinones
Synthesis of Piperlongumine Analogues and Discovery of Nuclear Factor Erythroid 2-Related Factor 2 (Nrf2) Activators as Potential Neuroprotective Agents
The cellular antioxidant system plays key roles in blocking or retarding the pathogenesis of adult neurodegenerative disorders as elevated oxidative stress has been implicated in the pathophysiology of such diseases. Molecules with the ability in enhancing the antioxidant defense thus are promising candidates as neuroprotective agents. We reported herein the synthesis of piperlongumine analogues and evaluation of their cytoprotection against hydrogen peroxide- and 6-hydroxydopamine-induced neuronal cell oxidative damage in the neuron-like PC12 cells. The structure-activity relationship was delineated after the cytotoxicity and protection screening. Two compounds (4 and 5) displayed low cytotoxicity and confer potent protection of PC12 cells from the oxidative injury via upregulation of a panel of cellular antioxidant molecules. Genetically silencing the transcription factor Nrf2, a master regulator of the cellular stress responses, suppresses the cytoprotection, indicating the critical involvement of Nrf2 for the cellular action of compounds 4 and 5 in PC12 cells.