Insulin-sensitizing effects of a novel alpha-methyl- alpha -phenoxylpropionate derivative in vitro

Metal-free highly chemo-selective bisphosphorylation and deoxyphosphorylation of carboxylic acids

Carboxylic acids are readily available in both the natural and synthetic world. Their direct utilization for preparing organophosphorus compounds would greatly benefit the development of organophosphorus chemistry. In this manuscript, we describe a novel and practical phosphorylating reaction under transition metal-free reaction conditions that can selectively convert carboxylic acids into the P-C-O-P motif-containing compounds through bisphosphorylation, and the benzyl phosphorus compounds through deoxyphosphorylation. This strategy provides a new route for carboxylic acid conversion as the alkyl source, enabling highly efficient and practical synthesis of the corresponding value-added organophosphorus compounds with high chemo-selectivity and wide substrate scope, including the late modification of complex APIs (active pharmaceutical ingredients). Moreover, this reaction also indicates a new strategy for converting carboxylic acids into alkenes by coupling this work and the subsequent WHE reaction with ketones and aldehydes. We anticipate that this new mode of transforming carboxylic acids will find wide application in chemical synthesis.

Bisphosphorylation of anhydrides - convenient access to bisphosphonates with a P-O-C-P motif

A novel strategy of bisphosphorylation of anhydrides with P(O)-H reagents via a DMAP-catalyzed and DBU-promoted process has been developed. These one-step transformations proceed efficiently to provide convenient access to a variety of P-O-C-P motif containing organophosphorus compounds. In addition, the gram-scale synthesis and the efficient recovery of the by-product highlight the sustainability and applicability of this method.

Synthesis and anticancer cytotoxicity with structural context of an α-hydroxyphosphonate based compound library derived from substituted benzaldehydes

We synthesized substituted benzaldehyde derived α-hydroxyphosphonates (αOHP), α-hydroxyphosphonic acids (αOHPA) and α-phosphinoyloxyphosphonates (αOPP) and characterized their cytotoxicity against a panel of cancer cell lines.

Application of network construction to estimate functional changes to insulin receptor substrates 1 and 2 in Huh7 cells following infection with the hepatitis C virus

Hepatitis C virus (HCV) is closely associated with insulin resistance (IS), acting primarily by interfering with insulin signaling pathways, increasing cytokine-mediated (tumor necrosis factor α, interleukin 6) inflammatory responses and enhancing oxidative stress. In the insulin signaling pathways, the insulin receptor substrate (IRS) is one of the key regulatory factors. The present study constructed gene regulatory sub-networks specific for IRS1 and IRS2 in Huh7 cells and HCV-infected Huh7 (HCV-Huh7) cells using linear programming and a decomposition algorithm, and investigated the possible mechanisms underlying the function of IRS1/2 in HCV-induced IS in Huh7 cells. All data were obtained from GSE20948 of the Gene Expression Omnibus database from the National Center for Biotechnology Information. Genes which were significantly differentially expressed between Huh7 and HCV-Huh7 cells were analyzed using the significance analysis of microarray algorithm. The top 50 genes, including IRS1/2, were used as target genes to determine the gene regulatory networks and next the sub-networks of IRS1 and IRS2 in HCV-Huh7 and Huh7 cells using Gene Regulatory Network Inference Tool, an algorithm based on linear programming and the decomposition process. The IRS1/2 sub-networks were divided into upstream/downstream groups and activation/suppression clusters, and were further analyzed using Molecule Annotation System 3.0 and Database for Annotation, Visualization, and Integrated Discovery software, two online platforms for enrichment and clustering analysis and visualization. The results indicated that in Huh7 cells, the downstream network of IRS2 is more complex than that of IRS1, indicating that the insulin metabolism in Huh7 cells may be primarily mediated by IRS2. In HCV-Huh7 cells, the downstream pathway of IRS2 is blocked, suggesting that this may be the underlying mechanism in HCV infection that leads to insulin resistance. The present findings add a further dimension to the understanding of the pathological mechanisms of HCV infection-associated insulin resistance, and provide novel concepts for insulin resistance and glucose metabolism research.

Synthesis and evaluation of novel oleanolic acid derivatives as potential antidiabetic agents

Antidiabetic agents simultaneously inhibiting hepatic glucose production and stimulating hepatic glucose consumption could apply a better control over hyperglycemia. A series of oleanolic acid derivatives with bulky substituents at C-3 position were designed and synthesized in order to search for this kind of agents. All of the compounds were evaluated biologically in vitro using glycogen phosphorylase and HepG2 cells. The results indicated that several derivatives exhibited moderate-to-good inhibitory activities against glycogen phosphorylase. Compound 8g showed the best inhibition with an IC50 value of 5.4 μm. Moreover, most of the derivatives were found to increase the glucose consumption in HepG2 cells in a dose-dependent manner. The possible binding mode of compound 8g with glycogen phosphorylase was also explored by docking study. 8g was found to have hydrogen bonding interactions with Arg193, Arg310, and Arg60 of the allosteric site.

Synthesis, characterization and vasculoprotective effects of nitric oxide-donating derivatives of chrysin

Vascular complications are major causes of disability and death in patients with diabetes mellitus. It is often characterized by endothelial dysfunction. Studies have shown that either the loss of nitric oxide bioactivity or the decreased biosynthesis of NO is a central mechanism in endothelial dysfunction. As such, the delivery of exogenous NO is an attractive therapeutic option that has been used to slow the progress of diabetic vascular complications. In this paper, a novel group of hybrid nitric oxide-releasing chrysin derivatives was synthesized. The results indicated that all these chrysin derivatives exhibited in vitro inhibitory activities against aldose reductase and advanced glycation end-products formation. And some of them were even found to increase the glucose consumption of HepG2 cells. Furthermore, all compounds released NO upon incubation with phosphate buffer at pH 7.4. These hybrid ester NO donor prodrugs offer a potential drug design concept for the development of therapeutic or preventive agents for vascular complications due to diabetes.