The objectives of this research were to determine total lipid content and corresponding fatty acid profiles in freshwater (n=10) marine fish (n=11) samples commonly consumed Bangladesh. Lipid was extracted by Solid Phase Dispersion method. Saponification esterification carried out the association official analytical chemists (AOAC) reference procedure with some simple modifications. acids analy...

Lactol carbocyclisations provide a succinct method of constructing the oxabicyclo[3.2.1]octane scaffold, motif present in various natural products medicinal interest. Lactols containing an unsaturated ketone or ester were prepared by olefin cross-metathesis; electrophilic alkene derived from methyl vinyl underwent concomitant terminal α-methylenation and oxa-Michael addition to give bridged lac...

The high diastereoselectivity in the Michael addition of nitromethane to α,β-unsaturated γ-amino esters, crystal conformations of β-nitromethane substituted γ-amino acids and peptides are studied. Results suggest that the N-Boc protected amide NH, conformations of α,β-unsaturated γ-amino esters and alkyl side chains play a crucial role in dictating the high diastereoselectivity of nitromethane ...

A protocol for the isothiourea-catalysed transfer hydrogenation of ?,?-unsaturated para-nitrophenyl esters using Hantzsch ester has been developed. Good to excellent yields are observed aryl bearing electron-withdrawing ?-substituents. The products can either be isolated directly in moderate (7 examples, 16–98%) or converted corresponding methyl (2 68–70% yield) benzyl amides 44–88% after situ ...

The proteolytic processing of polyproteins by the 3CL protease of severe acute respiratory syndrome coronavirus is essential for the viral propagation. A series of tripeptide a,b-unsaturated esters and ketomethylene isosteres, including AG7088, are synthesized and assayed to target the 3CL protease. Though AG7088 is inactive (IC50 > 100 lM), the ketomethylene isosteres and tripeptide a,b-unsatu...

Eleven novel dispiro-1,2,4,5-tetraoxanes 3 bearing unsaturated and polar functional groups were designed to enhance the oral antimalarial activity of the prototype tetraoxane 2 (WR 148999). With the exception of 3g and 3h, tetraoxanes 3 were available via the peroxidation of corresponding cyclohexanone derivatives in H2SO4/CH3CN. Tetraoxanes 3g and 3h were prepared by hydrolysis of ester tetrao...

Several compounds were evaluated in vitro as alternative electron sinks to ruminal methanogenesis. They were incubated with ruminal fluid, buffer mixture, and finely ground alfalfa hay for 24 h, at 0, 6, 12, and 18 mM initial concentrations. The propionate enhancer oxaloacetic acid, the butyrate enhancer beta-hydroxybutyrate, and the butyrate unsaturated analog 3-butenoic acid were ineffective ...

The presence of a strong contact component in the sex and ovipositing behavior of the sheep blowfly Lucilia cuprina Wied. prompted an investigation into the chemical composition of the cuticular wax of the adult male and female flies as well as that of the blowfly puparia. Thin-layer chromatography indicated that the lipids in all the waxes examined comprise hydrocarbons, nonglyceryl esters, tr...

We compared seven techniques, commonly used for detection of amniotic fluid phospholipids in thin-layer chromatography, with respect to their sensitivity to saturation of the fatty acid carbon-chain of lecithin. The techniques fell into two classes: sensitive and insensitive; those classed as saturation sensitive were less than or equal to 10% as sensitive to fully saturated lecithin as to leci...

olyester and vinyl ester resinbased linings are known for their solvent and chemical resistance. The different resins in these linings have broad resistance ranges, with acid resistance being a major strength. Some of the specific resins resist 1 or more chemicals or types of chemicals better than other resins, so systems often are finetuned by the choice of resin for a particular chemical envi...