THE BIOSYNTHESIS OF UBIQUINONE - SYNTHESIS AND ENZYMATIC MODIFICATIONOF BIOSYNTHETIC PRECURSORS

The synthesis of key intermediates in the eukaryotic biosynthetic path way of ubiquinone (Q) and the biotransformation of these materials wit h yeast (S. cerevisiae) mitochondria are described. The synthesis of Q aromatic precursors 2, 3, and 4 (n = 3 in all cases) relies on the pa lladium (0) catalyzed coupling of farnesyl tributylstannane with suita bly functionalized aryl halides. Preliminary experiments show that inc ubation of synthetic substrate 3 with mitochondria from yeast containi ng the 3,4-dihydroxy-5-hexaprenylbenzoate methyltransferase gene (COQ3 ) and S-[methyl-H-3]adenosyl-L-methionine yields radiolabeled 4. Copyr ight (C) 1996 Elsevier Science Ltd