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A combinatorial nickel-catalyzed monofluoroalkylation of aryl halides with unactivated fluoroalkyl halides by reductive cross-coupling has been developed. This method demonstrated high efficiency, mild conditions, and excellent functional-group tolerance, thus enabling the late-stage monofluoroalkylation of diverse drugs. The key to success was the combination of diverse readily available bidentate and monodentate pyridine-type nitrogen ligands with nickel, which in situ generated a variety of readily tunable catalysts to promote fluoroalkylation with broad scope with respect to both coupling partners. This combinatorial catalysis strategy offers a solution for nickel-catalyzed reductive cross-coupling reactions and provides an efficient way to synthesize fluoroalkylated druglike molecules for drug discovery.

Reported herein is a Rh-catalyzed redox-neutral annulation of primary benzamides with diazo compounds, representing an efficient and economic protocol to isoquinolinones. The procedure exhibited good functional group tolerability, scalability, and regioselectivity, obviating the need for oxidants, and only environmentally benign N2 and H2O were released. Further utilization of the method provided an alternative route to functionalized isoquinolines.

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Background: Compelling evidence suggests that SIRT1, NAD⁺-dependent class III protein deacetylase, plays an important role in the prevention and treatment of atherosclerosis by counteracting inflammation. Cluster of differentiation 40 (CD40), as a pro-inflammatory cytokine, has been shown to participate in the pathophysiology of atherosclerosis. The relationship between SIRT1 and CD40, however, remained elusive. The present study was thus designed to explore the potential effect of SIRT1 on CD40 expression induced by tumor necrosis factor-α (TNF-α) and to disclose the underlying mechanism in CRL-1730 endothelial cells. Methods: mRNA and protein expressions were identified by quantitative real-time PCR and Western blot respectively. Subcellular localization of SIRT1 was detected by immunofluorescence analysis. SIRT1 small-interfering RNA (siRNA) was carried out for mechanism study. Results: TNF-α reduced SIRT1 expression and induced CD40 expression in CRL-1730 endothelial cells in a time- and concentration- dependent manner. Pretreatment with resveratrol (a potent SIRT1 activator) inhibited TNF-α-induced CD40 expression, while pretreatment with nicotinamide (class b HDACs inhibitor nicotinamide) or sirtinol (a known SIRT1 inhibitor), especially SIRT1 siRNA significantly augmented TNF-α-induced CD40 expression. The frther sudy idicated that PDTC (NF-ĸB inhibitor) pretreatment attenuated TNF-α-induced CD40 expression, and SIRT1 siRNA significantly augmented TNF-α-induced acetylated-NF-ĸB p65 (Lys310) expression. Conclusion: The present study provides the direct evidence that SIRT1 can inhibit TNF-α- induced CD40 expression in CRL-1730 endothelial cells by deacetylating the RelA/p65 subunit of NF-ĸB at lysine 310, which provides new insights into understanding of the anti-inflammatory and anti-athroscerotic actions of SIRT1.