DNA Interstrand Cross-Link Formation Using Furan as a Masked Reactive Aldehyde

This unit describes a method for interstrand cross-linking between a furan-modified oligonucleotide and its unmodified complement. The synthesis of two furan-modified phosphoramidites, selected based on high cross-linking yield versus improved cross-linking selectivity, is described. The methods allow gram-scale synthesis starting from stable and readily available furan derivatives. Cross-linking requires selective oxidation of the furan moiety to an aldehyde. The masked nature of the latter avoids undesired and off-target reactions, resulting in clean and high-yield cross-link formation. Curr. Protoc. Nucleic Acid Chem. 54:5.12.1-5.12.16. © 2013 by John Wiley & Sons, Inc.