Fig. 2
From: The identification of carbon dioxide mediated protein post-translational modifications

Carbamate trapping on the ε-NH2 group of α-N-acetyl-lysine. a N-acetyl-lysine-carbamate formation and trapping (O-ethylation) by TEO. b 13C-NMR spectrum demonstrating the formation of a carbamate on N-acetyl-lysine by the appearance of a peak at 164 ppm