Psoralen C2 at the 5’-terminus of an oligonucleotide serves effectively as a cross-linking reagent in double-stranded oligonucleotides. The 6 atom spacer arm of Psoralen C6 allows cross-linking with a triplex oligonucleotide strand. Click Chemistry with psoralen azide and one of our many nucleosidic and non-nucleosidic alkyne derivatives has the potential to generate a variety of practical cross-linkers. The well known reversible cross-linking behavior of psoralen with an adjacent thymidine residue could be very useful.
Coupling: 10 minute coupling time recommended.
Deprotection: Mild: 0.4M Methanolic NaOH 17hr @ RT or ammonium hydroxide 24h @ RT|Note: NaOH is not compatible with dmf protecting groups.
Psoralens are a class of naturally occurring heterocyclic compounds which intercalates between bases in double-stranded or triple stranded DNA. Upon exposure to long wavelength light (350 nm) Psoralen forms covalent linkages to Thymidine (cyclobutane linkage). Psoralen is a bifunctional reagent and can form either a monoadduct, linking one adjacent thymidine on the same or complimentary strand, or a diadduct, linking adjacent thymidines on the same or complimentary strands. Diadducts formed between adjacent thymidines are photoreversable with short wavelength UV light (254 nm).