Tetrabutylammonium Iodide‐Catalyzed Phosphorylation of Benzyl C?H Bonds via a Cross‐Dehydrogenative Coupling (CDC) Reaction

Phosphate esters play important roles as biological active principles and synthons in chemistry. An efficient metal‐free approach for the synthesis of phosphate esters through sp³ C H activation is described. By using tetrabutylammonium iodide (Bu₄NI) as a catalyst and tert‐butyl hydroperoxide (TBHP) as an oxidant, various toluene derivatives and phosphorus nucleophiles are tolerated in this transformation, affording the corresponding products in moderate to good yields.

     

Silver‐Catalyzed Direct C${{_{sp{^{2}}}}}$?H Phosphorylation of Indoles Leading to Phosphoindoles

The silver carbonate‐catalyzed direct C  H phosphorylation of indoles in the presence of magnesium nitrate is described. The reaction affords selectively phosphonoindoles in moderate to good yields through a radical process. This protocol provides an efficient and general method for the preparation of 2‐ and 3‐phosphorylated indoles.

     

(?)-Epicatechin-3-O-β-d-allopyranoside from Davallia formosana,Prevents Diabetes and Hyperlipidemia by Regulation of Glucose Transporter 4 and AMP-Activated Protein Kinase Phosphorylation in High-Fat-Fed Mice

The purpose of this experiment was to determine the antidiabetic and lipid-lowering effects of (−)-epicatechin-3-O-β-d-allopyranoside (BB) from the roots and stems of Davallia formosana in mice. Animal treatment was induced by high-fat diet (HFD) or low-fat diet (control diet, CD). After eight weeks of HFD or CD exposure, the HFD mice were treating with BB or rosiglitazone (Rosi) or fenofibrate (Feno) or water through gavage for another four weeks. However, at 12 weeks, the HFD-fed group had enhanced blood levels of glucose, triglyceride (TG), and insulin. BB treatment significantly decreased blood glucose, TG, and insulin levels. Moreover, visceral fat weights were enhanced in HFD-fed mice, accompanied by increased blood leptin concentrations and decreased adiponectin levels, which were reversed by treatment with BB. Muscular membrane protein levels of glucose transporter 4 (GLUT4) were reduced in HFD-fed mice and significantly enhanced upon administration of BB, Rosi, and Feno. Moreover, BB treatment markedly increased hepatic and skeletal muscular expression levels of phosphorylation of AMP-activated (adenosine monophosphate) protein kinase (phospho-AMPK). BB also decreased hepatic mRNA levels of phosphenolpyruvate carboxykinase (PEPCK), which are associated with a decrease in hepatic glucose production. BB-exerted hypotriglyceridemic activity may be partly associated with increased mRNA levels of peroxisome proliferator activated receptor α (PPARα), and with reduced hepatic glycerol-3-phosphate acyltransferase (GPAT) mRNA levels in the liver, which decreased triacylglycerol synthesis. Nevertheless, we demonstrated BB was a useful approach for the management of type 2 diabetes and dyslipidemia in this animal model.