1997 Volume 45 Issue 6 Pages 1080-1084
Reaction of 5a-bromo-α-tocopherol with ascorbic acid produces 5a-tocopheryl ascorbate which is designated "vitamin CE." This novel tocopherol derivative represents an interesting prodrug form of α-tocopherol (vitamin E) that is stable under acidic conditions, but regenerates finely dispersed vitamin E in basic media. The reaction mechanism of the base-induced decomposition of vitamin CE involves elimination of ascorbate and production of an ortho-quinone methide intermediate that oxidizes ascorbate, and is reduced to vitamin E. Kinetic experiments showed the reaction to proceed in the pH range of 8 to 11 under physiological conditions. Tissue culture measurements demonstrated that vitamin E generated from the novel derivative is absorbed at much higher rates than conventional preparations and can even be absorbed under simulated conditions of malabsorption where there is no uptake of conventional vitamin E medications.
