Tetraethoxypropane

Effect of quercetin and genistein on copper- and iron-induced lipid peroxidation in methyl linolenate.[Pubmed: 12975775]

J Appl Toxicol. 2003 Sep-Oct;23(5):363-9.

The single and combined effects of two abundant flavonoids, namely quercetin and genistein, were investigated according to their ability to inhibit the oxidation of methyl linolenate via Fenton's pathway.
METHODS AND RESULTS:
Antioxidative activity was determined by oxidizing methyl linolenate suspended in a buffer solution with either Fe2+ (50 microM) or Cu2+ (50 microM) and hydrogen peroxide (0.01 mM) without or with a flavonoid sample (10 or 20 microM). Lipid peroxidation products were measured by the thiobarbituric acid (TBA) assay and the amounts of thiobarbituric acid-reactive substances (TBARS) were calculated from a calibration curve using 1,1,3,3-Tetraethoxypropane as the standard. Both quercetin and genistein at the 10 or 20 microM level decreased lipid peroxidation significantly compared with their respective controls. Of the two flavonoids tested, quercetin had a more marked effect on inhibiting lipid peroxides. Peroxidation products for the control samples were higher for the Fe2+-treated samples compared with the Cu2+ samples. Combination of both flavonoids at the same dose levels continued to decrease lipid peroxidation, the effect being the same for both metal ions.
CONCLUSIONS:
The data suggest that the combined flavonoids offered better protection than the single treatments and this may be attributed to the better radical scavenging or increased chelating capabilities of the combined over the single treatments. The differences in peroxide levels for the single treatment of quercetin compared with the genistein-treated samples may reflect the structural differences between these compounds in combating oxidative stress.

Journal of Labelled Compounds & Radiopharmaceuticals, 1985, 22(11):1175-9.

Synthesis of malondialdehyde-1-2H and malondialdehyde-1,3-2H2[Reference: WebLink]

Two synthetic routes for deuterium labelling of 1,1,3,3-Tetraethoxypropane, the precursor of the ubiquitous natural compound malondialdehyde, are described.
METHODS AND RESULTS:
In one scheme, deuterium is incorporated in ethyl vinyl ether by metalation with t-butyllithium followed by quenching with 2H2O. The conversion of the deuterated ether to monodeuterated Tetraethoxypropane, however, proceeds with an overall yield of only ˜5%. As an alternative route, we have metalated the bis-1,3-propylene dithioacetal of malondialdehyde which undergoes excellent deuterium incorporation (92%). In addition, the latter method allows isotopic labelling of either one or two deuterium(s) /molecule. Hydrolysis of the deuterated dithioacetal to the corresponding Tetraethoxypropane can be best effected by refluxing with HgO(red) /HgCl2/BF3. etherate in the presence of CH(OC2H5)3/C2H5OH. The overall yield of the method is 48%.