New synthesis of (+/-)-alpha-CMBHC and its confirmation as a metabolite ofalpha-tocopherol (Vitamin E)

There is currently interest in the metabolism of the Various compounds whic h make up the vitamin E family, especially with regards to the possible use of vitamin E metabolites as markers of oxidative stress and adequate vitam in E supply. A number of vitamin E metabolites have been described to date and we have recently developed a method to extract and quantitate a range o f vitamin E metabolites in human urine. During the development of this meth od a new metabolite of alpha -tocopherol was identified, which we tentative ly characterised as 5-(6-hydroxy-2,5,7,8-tetramethyl-chroman pentanoic acid (alpha -CMBHC).(1) Here we describe the synthesis of alpha -CMBHC as a sta ndard and confirm that it is a metabolite of cl-tocopherol. (C) 2001 Elsevi er Science Ltd. All rights reserved.