Ubiquinone formula

The body maintains an antioxidant network consisting of vitamins A, C, and E, antioxidant enzymes, and a group of related compounds called coenzyme Q, for which the general formula is shown. The n represents the number of times that a particular group is repeated it can be 6, 8, or 10. The coenzyme Q molecules are also called ubiquinones, because they are so ubiquitous in the body. Antioxidants are molecules that are easily oxidized and so react readily with radicals before the radicals can react with other compounds in the body. A variety of intricate mechanisms... 

Dehydroquinic acid, shikimic acid, and chorismic acid are carboxylated compounds containing a six-membered carbocyclic ring with one or two double bonds (Fig. 143). The secondary products derived from these substances either still contain the ring and the C -side chain of the acids (see the structure of the benzoic acid derivatives, of anthranilic and 3-hydroxyanthranilic esters, D 8, D 8.2, D 8.4 and D 8.4.1) or have additional rings (see the formulae of naphthoquinones and anthraquinones, D 8.1, of quinoline, acridine, and benzodiazepine alkaloids, D 8.3.2). The carbon skeletons may be substituted by isoprenoid side chains (see the structure of ubiquinones, D 8.3) and may carry different functional groups, e.g., hydroxy, carboxy, methoxy, and amino groups. 

Fig. C-60. Structure of ubiquinones (coenzymes Q). The "n" In the formula varies according to the source—it varies from 6 in some yeasts to 10 In mammalian liver.

We have formulated the reaction on the example of ubiquinone, also called coenzyme Q, which is particularly abundant in mitochondria. Several workers, furthermore, have proposed the participation of vitamin E quinone, of vitamin K (Martins), and — in plants—of plastoquinone. These quinones are grouped with the fat-soluble vitamins, but they will be discussed in Chapt. XIV because of their isoprenoid side chains. Their formulas will be shown there, too. Being lipids they are bound as mitochondrial lipoproteins or are at least associated with the lipoproteins. The quinones may be thought of as being incorporated in an orderly arrangement in the protein-lipid double layers of mitochondria. 

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