Methyltrioxorhenium (MTO) complexed with pyridine was shown to be a highly effective catalyst for the regioselective monoepoxidation of conjugated di- and trienes using 30% H2O2 at or below room temperature. The resultant allylic epoxides, and the triols derived from them, are versatile synthetic intermediates as well as substructures present in many bioactive natural products. The site of epox...

we studied the effect of different concentrations of alpha-tocopherol on in vitro cupric ions induced oxidation of low density lipoproteins (ldl). human native ldl (50 µg protein/ml) oxidation was induced by 10 µmol/l of cuso4. conjugated dienes were measured spectrophotometrically for up to 440 minutes. the length of the lag phase (tlag), maximum velocity of the reaction (vmax) and the maximum...

The conjugated polyene fatty acid parinaric acid (PnA) undergoes a stoichiometric loss in fluorescence upon oxidation and can be used to directly monitor peroxidative stress within lipid environments. We evaluated the course of potentially atherogenic oxidative changes in low density lipoproteins (LDL) by monitoring the oxidation of PnA following its incorporation into buoyant (p = 1.026-1.032 ...

Ene-yne cross-metathesis from alkynes and ethylene is a useful method to produce substituted conjugated butadiene derivatives. If this method has been used with aliphatic alkynes, it has however never been used starting from diarylacetylenes as internal alkynes. We show that the ene-yne cross-metathesis catalyzed by the second generation Hoveyda ruthenium catalyst provides the 2,3-diarylbuta-1,...

Methyl linolenate was hydrogenated with 1050 copper chromite catalyst at 150 C and atmospheric hydrogen pressure. The product was separated into monoene, diene and triene fractions by countercurrent distribution. These fractions were further separated into "arious geometrical isomers. The double bond location in the "arious fractions was determined b" reductiw ozonolysis. Double bonus in both c...

Ascorbate at concentrations of 60-100 microM inhibits the modification of freshly prepared low-density lipoprotein (LDL) by macrophages. With 'moderately oxidized' LDL (produced by prolonged storage in a refrigerator), however, ascorbate does not inhibit LDL modification by macrophages and actually modifies the LDL itself in the absence of macrophages [Stait and Leake (1994) FEBS Lett. 341, 263...

The intake of antioxidants intake has been reported to be inversely associated with the incidence of coronary artery disease. To clarify the possible role of lipophilic antioxidants in prevention of atherosclerosis, we investigated the effects of lycopene on the susceptibility of low-density lipoprotein (LDL) to oxidative modification. In this study, “lycopene” was added to plasma and incubated...

The use of a Co(porphyrin)-amide ligand, , in the palladium(II)-catalyzed 1,4-diacetoxylation of conjugated dienes under O2 results in aerobic oxidation. The catalyst was highly active under O2, and the 1,4-diacetoxylation reaction could also be performed under air.