An efficient synthesis of futalosine

Futalosine is a naturally occurring nucleoside comprised of an inosine core with a 3-carboxyphenyl methylene ketone functionality replacing the C-5′ hydroxyl. Recent studies have shown that it is a key intermediate in an alternative biosynthetic pathway that generates menaquinone in a variety of bacterial species. Here we report the first synthesis of futalosine in seven steps from inosine in an overall 17% yield. This work will enable further studies on menaquinone biosynthesis in pathogenic bacteria.