Palladium-Catalyzed Cyanation of Nucleobases: Total Synthesis of Toyocamycin, Sangivamycin, and a Mycalisine A Precursor

Abstract

Installation of cyano group functionality onto nucleosides has always been a challenging task for chemists, and catalytic protocols developed for simple aryl substrates have, in most cases, failed to replicate their success when applied to nucleobase or sugar moieties of nucleosides. Given the importance of the cyano and amide functionalities in nucleoside chemistry, we herein disclose an efficient Pd-catalyzed cyanation protocol specifically applied to iodo nucleobases. Furthermore, the developed cyanation method has been explored for the synthesis of naturally occurring and bioactive nucleosides such as toyocamycin, sangivamycin, and a mycalisine A precursor.

Key words

nucleosides - toyocamycin - sangivamycin - palladium catalysis - cyanation - late-stage modification

• References and Notes

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