Ambient Temperature Synthesis of Triazole-4-carbaldehyde Reagent by Dimroth Rearrangement Enabling Facile N‑Terminal-specific Modification and Immobilization of Proteins

A facile method for the preparation of the N-terminal-specific
modification reagent, 1H-1,2,3-triazole-4-carbaldehyde
(TA4C), using 1-(4-cyano-2,3,5,6-tetrafluorophenyl)-1H-1,2,3-triazole-4-carbaldehyde derivative precursors, has been developed.
This method allows direct conversion from a starting compound tethering
a primary amine through the Dimroth rearrangement reaction at 25 °C.
The resulting TA4C reagent exhibits excellent specificity for the
N-terminal modification of proteins. The TA4C reagent enables versatile
protein conjugation to various functional molecules, including useful
handles and functional groups such as azides, alkynes, and amino acid
derivatives. Furthermore, this method also facilitates N-terminal-specific
immobilization of proteins onto resins, allowing the purification
of N-terminal-modified proteins from unmodified proteins. The proteins
and enzymes immobilized onto the resin via the N-terminus fully retain
their inherent functions.