5′-Porphyrin-oligonucleotide conjugates:: Neutral porphyrin-DNA interactions

[GRAPHICS] Incorporation of hydrophilic tetraarylporphyrin phosphoramidites into the 5'-termimus of the DNA as well as noncharged porphyrin-DNA interactions have been studied. Porphyrin-modified oligonucleotides show lower melting temperatures than their unmodified analogues. Single-stranded DNA interacts more strongly with porphyrin and causes more intense chiral disturbance in the porphyrin environment than the corresponding double strand.