Efficient preparation of carbohydrate–oligonucleotide conjugates (COCs) using oxime bond formation

Chemoselective ligation of carbohydrates to oligonucleotides was accomplished by oxime bond formation. The conjugation was performed by reacting an oxyamino sugar with an oligonucleotide containing an aldehyde moiety at the 5′-end. The carbohydrate–oligonucleotide conjugates (COCs) were obtained in good yield without the need of a protection strategy and under mild aqueous conditions.