Structure of the Tocopherols and Tocotrienols

The tocopherols comprise four compounds all of which are methyl derivatives of tocol, 2-methyl-2-(4 ,8 ,12 -trimethyldecyl)-6-chromanol. 

Some years after the isolation of the four tocopherols the four tri-unsaturated analogues, the tocotrienols were discovered. They are 8-methyl, 5,8- and 7,8-dimethyl and 5,7,8-trimethyl derivatives repectively of tocotrienol, 2R-methyl-2-(4, 8, 12-trimethyldeca-3, 7, 11 -trienyl)-6-chromanol. a-Tocotrienol is shown. 

A plastoquinol is depicted in which the methyl group ( ) is that resulting from biological methylation. 

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