Covalently Mercurated 6‐Phenylcarbazole Residues Promote Hybridization of Triplex‐Forming Oligonucleotides

: Ukale, Dattatraya Uttam; Lönnberg, Tuomas

Publisher: Wiley

: WEINHEIM

: 2025

: ChemBioChem

: CHEMBIOCHEM

: e202401006

: 8

: 1439-4227

: 1439-7633

DOI: https://doi.org/10.1002/cbic.202401006(external)

: https://doi.org/10.1002/cbic.202401006(external)

: https://research.utu.fi/converis/portal/detail/Publication/485153979(external)

Homothymidine DNA oligonucleotides bearing a 3'-terminal 6-phenyl-9H-carbazole C-nucleoside, mercurated at position 1, 8 or both, were synthesized and tested for their potential to form triple helices with homoadenine & sdot; homothymine duplexes. The monomercurated triplex-forming oligonucleotides favored hybridization with fully matched double helices and in some cases considerable increase of the melting temperature could be attributed to Hoogsteen-type Hg(II)-mediated interaction with the homoadenine strand. The dimercurated one, on the other hand, favored hybridization with double helices placing a homo mispair opposite to the carbazole residue, suggesting that simultaneous coordination of each of the two Hg(II) ions to a different strand is only possible in the absence of competition from Watson-Crick base pairing.

:
Finnish Cultural Foundation