Search

Herein, a highly regioselective propargylic benzylation with propargylic carbonates and benzyl 1,4-dihydropyridine derivatives was developed via a photoredox/palladium dual-catalyzed process, which represents a novel catalytic model for non-terminal propargylic functionalization. The reaction showed excellent regioselectivity and functional group compatibility. A radical coupling mechanism between the propargylic radical and benzyl radical was proposed. [ABSTRACT FROM AUTHOR]

The development of a robust strategy for the effective removal of oils and organic pollutants should be of great technological significance for addressing severe environmental issues. Here we report the synthesis of superhydrophobic aminopyridine-containing conjugated microporous polymers (APCMPs) for oil/water separation through a simple one-pot coupling reaction. The resulting APCMPs show high thermal stability with a decomposition temperature of up to 300°. Wettability measurements show that all four kinds of APCMPs have a water contact angle (WCA) of higher than 150° and an oil contact angle of about zero, indicating excellent superhydrophobicity and superoleophilicity which have great advantages over those traditional approaches for the construction of superhydrophobic surfaces that usually suffer from a number of drawbacks such as the need for complicated techniques, multi-step processes or high production cost. By decoration of commercially available cotton threads with the as-synthesized APCMPs, a continuous oil/water separation instrument was designed and fabricated with high oil/water separation efficiency. Due to their physicochemical robustness, excellent superwetting ability, and simple and scalable production, such APCMPs may hold great potential as superwetting porous materials or coatings for oil spilling cleanup or other pollution removal applications. [ABSTRACT FROM AUTHOR]

Precursor-fed cultivation of endophytic Chaetomium globosum1C51 afforded nine novel “unnatural” halogenated chaetoglobosins including those with more preferable immunosuppressive activity. [ABSTRACT FROM AUTHOR]

Attempted synthesis of sterically demanding tris-β-diketiminate complexes of europium led to oxidation–coupling of β-diketiminates and the formation of the THF-solvated divalent europium complex Eu(L2,6-Me2)2(THF) (L2,6-Me2= [{N(2,6-Me2C6H3)C(Me)}2CH]−), while the normal tris-β-diketiminate complex Eu(L2-Me)3for the less bulky ligand L2-Me([{N(2-MeC6H4)C(Me)}2CH]−) was isolated by the same procedure. [ABSTRACT FROM AUTHOR]

Onion has been shown to favorably modify the lipoprotein profile. However, research on its underlying mechanism is lacking. The present study investigated the interaction of dietary onion powder with the protein expression of key receptors and enzymes involved in cholesterol metabolism. Thirty-six male hamsters were randomly divided into three groups and fed a high-cholesterol control diet or the two experimental diets supplemented with 1% onion powder (OP-1) or 5% onion powder (OP-5), for a period of 8 weeks. It was found that onion dose-dependently decreased plasma total cholesterol (TC) level. The change in plasma lipoprotein profile was accompanied by a greater excretion of both fecal neutral and acidic sterols. Western blot analysis revealed that onion up-regulated sterol regulatory element binding protein 2 (SREBP-2), liver X receptor alpha (LXRα) and cholesterol-7α-hydroxylase (CYP7A1) with no effect on 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) and LDL receptor (LDL-R). It was concluded that the hypocholesterolemic activity of onion powder was mediated by enhancement of fecal sterol excretion and up-regulation of LXRα and CYP7A1., (This journal is © The Royal Society of Chemistry 2010)