Tunicamycin: chemical synthesis and biosynthesis.

Tunicamycins are nucleoside natural products and show antibacterial, antiviral and antitumor activities, which are attributed to their inhibition of enzymatic reactions between polyisoprenyl phosphate and UDP-GlcNAc or UDP-MurNAc-pentapeptide. Because of their various intriguing biological activities, tunicamycins have potential as therapeutic agents for infectious diseases or cancers. Structurally, tunicamycins have a unique structure composed of an undecodialdose skeleton, a lipid chain and a GlcNAc fragment linked by a 1,1-β,α-trehalose-type glycosidic bond. In this mini review, we summarize the total chemical syntheses and biosynthetic studies of tunicamycins.