Synthesis of new biotin derivatives

It is now established that the formation of C-S bonds during the conversion of dethiobiotin into biotin involves intermediate carbon radicals. To exam ine the behavior of dethiobiotin analogs that could lead to allylic and alp ha-epoxyradicals, we have synthesized 4,5-dehydrodethiobiotins and the corr esponding epoxides and 5,6-dehydrodethiobiotins. All these compounds have b een labelled with C-14 On the carboxyl group. (C) 1999 Elsevier Science Ltd . All rights reserved.