The Oxidation of Aldehydes to Methyl Esters using Trichloroisocyanuric Acid

Aldehydes are readily oxidized to methyl esters by a solution of methanol, pyridine, and trichloroisocyanuric acid in acetonitrile, acetone, or methylene chloride.     

Synthesis of aurachin D and isoprenoid analogues from the myxobacterium Stigmatella aurantiaca

Aurachins, a family of isoprenoid quinoline alkaloids isolated from the myxobacterium Stigmatella aurantiaca, possess multiple interesting bioactivities and were subject of intensive studies of biosynthesis. In this Letter, we describe the efficient few step total synthesis of the parent compound aurachin D and two isoprenoid analogues via Conrad–Limpach cyclization. The main antimicrobial and cytotoxic profiles of these derivatives were explored.     

Synthesis of rapamycin glycoconjugates via a CuAAC-based approach

The conversion of the C40 secondary hydroxyl group of rapamycin into the azido group was followed by copper catalyzed cycloaddition of the resulting azido-rapamcin with various unprotected propargyl O- and S-glycosides and a C-ethynyl derivative. This approach furnished a collection of triazole-bridged rapamycin glycoconjugates (14 examples) in 44–83% isolated yield.     

Determination of GDC‐0980 (apitolisib), a small molecule dual phosphatidylinositide 3‐kinase/mammalian target of rapamycin inhibitor in dog plasma by LC‐MS/MS to support a GLP toxicology study

An LC‐MS/MS method for the determination of GDC‐0980 (apitolisib) concentrations in dog plasma has been developed and validated for the first time to support pre‐clinical drug development. Following protein precipitation with acetonitrile, the resulting samples were analyzed using reverse‐phase chromatography on a Metasil AQ column. The mass analysis was performed on a triple quadruple mass spectrometer coupled with an electrospray interface in positive ionization mode. The selected reaction monitoring transitions monitored were m/z 499.3 → 341.1 for GDC‐0980 and m/z 507.3 → 341.1 for IS. The method was validated over the calibration curve range 0.250–250 ng/mL with linear regression and 1/x² weighting. Relative standard deviation (RSD) ranged from 0.0 to 10.9% and accuracy ranged from 93.4 to 113.6% of nominal. Stable‐labeled internal standard GDC‐0980‐d₈ was used to minimize matrix effects. This assay was used for the measurement of GDC‐0980 dog plasma concentrations to determine toxicokinetic parameters after oral administration of GDC‐0980 (0.03, 0.1 and 0.3 mg/kg) to beagle dogs in a GLP toxicology study. Peak concentration ranged from 3.23 to 84.9 ng/mL. GDC‐0980 was rapidly absorbed with a mean time to peak concentration ranging from 1.3 to 2.4 h. Mean area under the concentration–time curve from 0 to 24 hours ranged from 54.4 to 542 ng h/mL. Copyright © 2015 John Wiley & Sons, Ltd.     

Mesoporous aluminosilicate macrospheres obtained by spray gelling technique

Journal of Sol-Gel Science and Technology - Porous aluminosilicate macrospheres were prepared by spray gelling technique using chitosan, chitosan and yeast cells and respectively chitosan, yeast...     

Polyaniline nanostructure electrode: morphological control by a hybrid template

Journal of Solid State Electrochemistry - We report here a novel approach to the template-assisted electrochemical synthesis of vertically aligned polyaniline (PANI) nanostructure surface arrays....     

The Relationships Between Sulphate Reduction and COD/VFA Utilisation Using Grass Cellulose as Carbon and Energy Sources

The release of mine effluents can have a damaging impact on receiving water bodies. Therefore, treatment of mine waters before discharge is imperative. A novel biological SO₄^{2 -} {\hbox{SO}}_4^{2 - } removal technology has been developed whereby the degradation/fermentation products of grass cellulose, volatile fatty acids (VFA), function as the electron donors and SO₄^{2 -} {\hbox{SO}}_4^{2 - } as the electron acceptor. The aim of the study presented here was to elucidate the interactions between the cellulose degradation rate, the chemical oxygen demand (COD), VFA production and its/utilisation rate as well as the sulphate reduction rate. To this end, two stirred batch reactors were operated: a test and a control reactor. The results showed that high COD and VFA concentrations were achieved after cellulose degradation, which resulted in a rapid decrease in the SO₄^{2 -} {\hbox{SO}}_4^{2 - } concentration in the test reactor. The VFA results indicated that propionic and butyric acids were preferentially utilised, producing acetate. In the control reactor, the VFA and the COD production increased initially at the same rate, followed later by a decrease at a similar rate. These results suggest that the degradation products formed were utilised by the methanogenic bacteria to produce methane rather than by the sulphate-reducing bacteria, since the control reactor contained no sulphate (Visser 1995). Furthermore, these results showed a clear relationship between the COD/VFA production and the SO₄^{2 -} {\hbox{SO}}_4^{2 - } reduction in the test reactor and between the COD and VFA pattern in the control reactor.