Diazo group as a new chemical reporter for bioorthogonal labelling of biomolecules

Diazoacetyl groups undergo spontaneous cycloaddition with strained alkenes and alkynes and can be bioorthogonal reporter groups labelling proteins and glycans.

Diazoacetyl groups have been shown to undergo spontaneous cycloaddition reactions with strained alkenes and alkynes. The rates of reaction are similar to the equivalent reactions of azide groups. This allows diazo groups to be used as bioorthogonal reporter groups. This is demonstrated by fluorescent labelling of a diazoacetylated protein and of cell-surface glycans via metabolic incorporation of a diazoacetylated sugar.