Synthesis and Application of D- and 13 C-Labelled tert-Butyl Hoechst Dye

Herein, the successful syntheses of D - and C-N-methyl and D -tert-butyl Hoechst dyes are presented. This includes the preparation of the labelled D - and C-N-methyl piperazines and D -tert-butylated hydroxytoluene precursors. The tert-butyl Hoechst dye is known to bind a specific RNA aptamer. Spectroscopic NMR studies of the labelled Hoechst dye-aptamer complexes allowed for the unambiguous assignment of chemical shifts, as well as the dynamics of the bound dye.