Intraduplex Photo-cross-linking of p-Azidoaniline Residue and Amino Acid Side Chains Linked to the Complementary Oligonucleotides via a New Phosphorylating Intermediate Formed in the Mukaiyama System

Abstract

Oligonucleotide derivatives carrying a side chain of either lysine or histidine at the 3′-end and their complementary oligonucleotides having photoreactive groups a p-azidophenyl-NH(CH2)_nNH- (n = 4, 6) residue at the 5′-end were prepared by using new phosphorylating species formed by treatment of oligonucleotides with Ph3P and (PyS)₂ or (PyrS)₂. in DMF, DMSO or their mixture. Efficient cross-linking of duplexes occurred under UV-irradiation (λ > 300 nm).