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Updated: Jul 8, 2026

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Synthesis and circular dichroism of tetraarylporphyrin-oligonucleotide conjugates
Milan Balaz1, Andrea E Holmes, Michele Benedetti
1Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA.
Abstract:
The preparation and circular dichroic (CD) studies of self-complimentary 8-mer DNA sequences with a porphyrin at the 3' end are presented. Electronic interaction between the two porphyrins (the interchromophoric distance is in the range of 28-40 A), attached to both ends of the double-stranded helix, gives rise to a long-range exciton-coupled CD in the visible region (400-450 nm). The porphyrin chromophores act as sensitive probes of geometrical changes in the DNA backbone and sensitively reflect the double-strand to single-strand transition. This study demonstrates the possibility of using exciton-coupled porphyrin CDs for conformational studies of DNA.
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