Copper dipyridine dichloride as a mild and efficient catalyst for a one pot condensation bigenelli reaction

The condensation reaction of aldehydes, β‐ketoesters and urea/thiourea in presence of a catalytic amount of CuPy₂Cl₂ complex proceeded under very mild reaction conditions in high yield (80‐90%).     

Regio- and stereoselective transfer of p-toluenesulfonamido group from sulfur to carbon: preparation of aminoalcohol derivatives from allylalcohols

A novel methodology for the regio- and stereoselective synthesis of amino alcohol derivatives from allylalcohols/ethers via intramolecular nucleophilic participation by the sulfilimine moiety is disclosed. The sulfilimine moiety is stereospecifically transformed to a sulfinyl moiety with an inverted configuration. The reaction is general and affords highly functionalised products.     

Pomegranate fruit extract modulates UV-B-mediated phosphorylation of mitogen-activated protein kinases and activation of nuclear factor kappa B in normal human epidermal keratinocytes paragraph sign

Excessive exposure of solar ultraviolet (UV) radiation, particularly its UV-B component, to humans causes many adverse effects that include erythema, hyperplasia, hyperpigmentation, immunosuppression, photoaging and skin cancer. In recent years, there is increasing use of botanical agents in skin care products. Pomegranate derived from the tree Punica granatum contains anthocyanins (such as delphinidin, cyanidin and pelargonidin) and hydrolyzable tannins (such as punicalin, pedunculagin, punicalagin, gallagic and ellagic acid esters of glucose) and possesses strong antioxidant and anti-inflammatory properties. Recently, we have shown that pomegranate fruit extract (PFE) possesses antitumor promoting effects in a mouse model of chemical carcinogenesis. To begin to establish the effect of PFE for humans in this study, we determined its effect on UV-B-induced adverse effects in normal human epidermal keratinocytes (NHEK). We first assessed the effect of PFE on UV-B-mediated phosphorylation of mitogen-activated protein kinases (MAPK) pathway in NHEK. Immunoblot analysis demonstrated that the treatment of NHEK with PFE (10-40 microg/mL) for 24 h before UV-B (40 mJ/cm(2)) exposure dose dependently inhibited UV-B-mediated phosphorylation of ERKl/2, JNK1/2 and p38 protein. We also observed that PFE (20 microg/mL) inhibited UV-B-mediated phosphorylation of MAPK in a time-dependent manner. Furthermore, in dose- and time-dependent studies, we evaluated the effect of PFE on UV-B-mediated activation of nuclear factor kappa B (NF-kappaB) pathway. Using Western blot analysis, we found that PFE treatment of NHEK resulted in a dose- and time-dependent inhibition of UV-B-mediated degradation and phosphorylation of IkappaBalpha and activation of IKKalpha. Using immunoblot analysis, enzyme-linked immunosorbent assay and electrophoretic mobility shift assay, we found that PFE treatment to NHEK resulted in a dose- and time-dependent inhibition of UV-B-mediated nuclear translocation and phosphorylation of NF-kappaB/p65 at Ser(536). Taken together, our data shows that PFE protects against the adverse effects of UV-B radiation by inhibiting UV-B-induced modulations of NF-kappaB and MAPK pathways and provides a molecular basis for the photochemopreventive effects of PFE.     

Model of diffusion-drift charge carrier transport in layers with a fractal structure

A new theoretical (semiempirical) model of diffusion-drift charge carrier transport in layers with a fractal structure based on a partial differential equation with a fractional time derivative has been proposed. It has been shown by numerical calculations that a decrease in the order of the fractional derivative in the presence of the external electric field leads to broadening and asymmetry of the spatial distributions of charge carriers, which physically corresponds to intensification of scattering processes.     

Ab-initio calculations of structural,electronic,and optical properties of Zn_3(VO_4)_2

The structural, electronic, and optical properties of Zn_3(VO_4)_2 are investigated using full potential linearized augmented plane wave(FP-LAPW) method within the framework of density functional theory(DFT). Various approaches are adopted to treat the exchange and correlation potential energy such as generalized gradient approximation(GGA),GGA+U, and the Tran–Blaha modified Becke–Johnson(TB-mBJ) potential. The calculated band gap of 3.424 eV by TB-mBJ is found to be close to the experimental result(3.3 eV). The optical anisotropy is analyzed through optical constants,such as dielectric function and absorption coefficient along parallel and perpendicular crystal orientations. The absorption coefficient reveals high absorption(1.5 × 10~(6) cm~(-1)) of photons in the ultraviolet region.     

Medicinal Potential of Isoflavonoids: Polyphenols That May Cure Diabetes

In recent years, there is emerging evidence that isoflavonoids, either dietary or obtained from traditional medicinal plants, could play an important role as a supplementary drug in the management of type 2 diabetes mellitus (T2DM) due to their reported pronounced biological effects in relation to multiple metabolic factors associated with diabetes. Hence, in this regard, we have comprehensively reviewed the potential biological effects of isoflavonoids, particularly biochanin A, genistein, daidzein, glycitein, and formononetin on metabolic disorders and long-term complications induced by T2DM in order to understand whether they can be future candidates as a safe antidiabetic agent. Based on in-depth in vitro and in vivo studies evaluations, isoflavonoids have been found to activate gene expression through the stimulation of peroxisome proliferator-activated receptors (PPARs) (α, γ), modulate carbohydrate metabolism, regulate hyperglycemia, induce dyslipidemia, lessen insulin resistance, and modify adipocyte differentiation and tissue metabolism. Moreover, these natural compounds have also been found to attenuate oxidative stress through the oxidative signaling process and inflammatory mechanism. Hence, isoflavonoids have been envisioned to be able to prevent and slow down the progression of long-term diabetes complications including cardiovascular disease, nephropathy, neuropathy, and retinopathy. Further thoroughgoing investigations in human clinical studies are strongly recommended to obtain the optimum and specific dose and regimen required for supplementation with isoflavonoids and derivatives in diabetic patients.     

Control over the Self‐Assembly Modes of PtII Complexes by Alkyl Chain Variation: From Slipped to Parallel π‐Stacks

We report the self‐assembly of a new family of hydrophobic, bis(pyridyl) Pt^II complexes featuring an extended oligophenyleneethynylene‐derived π‐surface appended with six long (dodecyloxy ( 2 )) or short (methoxy ( 3 )) side groups. Complex 2 , containing dodecyloxy chains, forms fibrous assemblies with a slipped arrangement of the monomer units (d_Pt???Pt≈14 Å) in both nonpolar solvents and the solid state. Dispersion‐corrected PM6 calculations suggest that this organization is driven by cooperative π–π, C?H???Cl and π–Pt interactions, which is supported by EXAFS and 2D NMR spectroscopic analysis. In contrast, nearly parallel π‐stacks (d_Pt???Pt≈4.4 Å) stabilized by multiple π–π and C?H???Cl contacts are obtained in the crystalline state for 3 lacking long side chains, as shown by X‐ray analysis and PM6 calculations. Our results reveal not only the key role of alkyl chain length in controlling self‐assembly modes but also show the relevance of Pt‐bound chlorine ligands as new supramolecular synthons.