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We report a direct, simple, and straightforward approach for the construction of a mixed monosilyl acetal as a new and synthetically valuable functional group by mixing an aldehyde, sodium tert-butoxide, and trimethylsilyl azide. We also demonstrate a catalyst-dependent chemoselective reaction between mixed monosilyl acetals and silyl ketene acetals through Mukaiyama aldol reactions to give different structures of O-protected β-hydroxy esters in excellent yields with high chemoselectivities. This study provided the existence of an oxonium ion intermediate and of its kinetically controlled reaction with the pre-equilibrated silyl enol ether obtained from (E)- and (Z)-isomerization.

Hydrogen sulfide (H2S) is a potent vasodilator and regulates cardiovascular homeostasis. Furthermore, H2S has a crucial role in ischemia−reperfusion injuries, especially of the heart, liver, and kidneys. This study indicates that treatment with hydrogen sulfide is able to restore neurological function after ischemic stroke by promoting angiogenesis. Treatment with H2S augments angiogenesis in the peri-infarct area, and it significantly improves functional outcomes after 2 weeks in a rat MCAO model. H2S promotes the phosphorylation of AKT and ERK and increases the expression of vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1). H2S-treated rats showed more newly synthesized endothelial cells in the ischemic lesion (2.31-fold, P

Aryl- and alkyl substituted enals react according to the regioselective title reaction to form a mixture of three diastereomeric cyclopropanation products in high yields and with often very high enantioselectivities.

Herein, we describe the first enantioselective cyclopropanation of enals using benzyl chlorides as bifunctional (nucleophilic and electrophilic) reagents. The reaction is simply catalyzed by chiral secondary amines to afford the formyl cyclopropane derivatives in good yields with moderate to excellent stereoselectivities.

Uniform 3 nm-sized ceria nanoparticles can protect against ischemic stroke by scavenging reactive oxygen species (ROS) and reducing apoptosis. PEGylated ceria nanoparticles showed protective effects against ROS-induced cell death in vitro. Optimal doses of ceria nanoparticles reduced infarct volumes and the rate of ischemic cell death in vivo.

Hydrogen sulfide (H2 S) is a potent vasodilator and regulates cardiovascular homeostasis. Furthermore, H2 S has a crucial role in ischemia-reperfusion injuries, especially of the heart, liver, and kidneys. This study indicates that treatment with hydrogen sulfide is able to restore neurological function after ischemic stroke by promoting angiogenesis. Treatment with H2 S augments angiogenesis in the peri-infarct area, and it significantly improves functional outcomes after 2 weeks in a rat MCAO model. H2 S promotes the phosphorylation of AKT and ERK and increases the expression of vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang-1). H2 S-treated rats showed more newly synthesized endothelial cells in the ischemic lesion (2.31-fold, P 0.01). H2 S-treated astrocytes increased VEGF and Ang-1 expression, and the inhibition of phosphatidylinositide 3-kinase (PI3K)/AKT signaling by LY294002 significantly reduced H2 S-induced VEGF and Ang-1 expression in astrocytes. Finally, H2 S stimulated endothelial cell migration (3.92-fold increase in wound healing assay) and tube formation (3.69-fold increase, P 0.001) through PI3K/AKT signaling. In conclusion, treatment with H2 S promotes angiogenesis and thereby contributes to improvement of functional outcome after cerebral ischemia. Our findings strongly suggest that H2 S may be of value in regenerative recovery after stroke.