the enzymatic hydrolysis of meso-1,7-diacetoxy-2,6-dimethylheptane 5, prepared from 2,6-dimethylhepta-1,6-diene 6, gave the (2s,6r)-7-acetoxy-2,6-dimethyl-1-heptanol 1, which was transformed to the (2r,6r)-2,6,10-trimethyl-1-undecanol 7. in this manner, the c14 side chain of a-tocopherol was synthesized from 2,6-dimethylhepta-1,6-diene 6 in only 5 steps.

Carotenoids and alpha-tocopherol are dietary, lipophilic antioxidants that may protect plasma lipoproteins from oxidation, a process believed to contribute to atherogenesis. Previous work demonstrated that after the Cu(II)-initiated oxidation of human low density lipoprotein (LDL) in vitro, carotenoids and alpha-tocopherol were destroyed before significant lipid peroxidation took place, and tha...

1. Mean concentration of serum alpha-tocopherol (Vitamin E) in 28 free-living black rhinoceroses sedated during translocation in Zimbabwe was 1.92 (SD, 0.43) mg/l. 2. Alpha-tocopherol was not detectable (less than 0.15 mg/l) in five captive black rhinoceroses held at London Zoo. 3. Circulating levels of all-trans retinol (Vitamin A) were not different between the two groups. 4. The low level of...

When most people think of vitamin E, more often than not they think of tocopherols—the most prominent being alpha-tocopherol. However, vitamin E refers to a family of eight distinct compounds: four tocopherols and four tocotrienols. While most people are familiar with alpha-tocopherol, other tocopherol forms include beta-, gamma-, and delta-. Similarly, the vitamin E family includes alpha-, bet...

BACKGROUND AND PURPOSE In the Alpha Tocopherol, Beta Carotene Cancer Prevention Study, alpha tocopherol supplementation decreased risk of cerebral infarction by 14% (95% CI, -25% to -1%), and beta carotene increased risk of intracerebral hemorrhage by 62% (95% CI, 10% to 132%). We report here the 6-year postintervention effects of alpha tocopherol and beta carotene supplementation on stroke and...

Cholesterol oxides, in particular 7-ketocholesterol, are proatherogenic compounds that induce cell death in the vascular wall when localized in lipid raft domains of the cell membrane. Deleterious effects of 7-ketocholesterol can be prevented by vitamin E, but the molecular mechanism involved is unclear. In this study, unlike gamma-tocopherol, the alpha-tocopherol vitamin E form was found to pr...

Inhibition of rat intestinal retinyl ester hydrolase by alpha-tocopherol (vitamin E) and phylloquinone (vitamin K1) was non-competitive. Maximum inhibition occurred within 10 min, and, particularly with alpha-tocopherol, was substantially reversible. Consequently, increasing tissue concentrations of retinyl esters, which might occur with advancing age or changes in diet, would not diminish the ...

Rats pre-administered with alpha-tocopherol (10 mgs/day) for 7 days afforded a significant protection at the tissue level against the lowering of superoxide dismutase and glutathione peroxidase, especially the selenium-dependent glutathione peroxidase. The protective action of alpha-tocopherol in the diethyldithiocarbamate treated rats may be attributed to its antioxidant/free radical scavengin...

OBJECTIVE To analyze the impact of low levels of testosterone induced by orchiectomy and the effect of alpha-tocopherol supplementation on oxidative stress in the urethral sphincter. MATERIALS AND METHODS Forty male Wistar rats weighing 250-300 g were divided into four groups with 10 each: Sham group; Orchiectomy group: bilateral orchiectomy; Orchiectomy-pre-Tocopherol group: bilateral orchie...