Abstract
The structure and properties of 18 hairpin-forming bis(oligonucleotide) conjugates possessing stilbene diether linkers are reported. Conjugates possessing bis(2-hydroxyethyl)stilbene 4,4′-diether linkers form the most stable DNA hairpins reported to date. Hairpins with as few as two T:A base pairs or four noncanonical G:G base pairs are stable at room temperature. Increasing the length of the hydroxyalkyl groups results in a decrease in hairpin thermal stability. On the basis of the investigation of their circular dichroism spectra, all of the hairpins investigated adopt B-DNA structures, except for a hairpin with a short poly(G:C) stem which forms a Z-DNA structure. Both the strong fluorescence of the stilbene diether linkers and their trans-cis photoisomerization are totally quenched in hairpins possessing neighboring T:A and G:C base pairs. Quenching is attributed to an electron-transfer mechanism in which the singlet stilbene serves as an electron donor and T or C serves as an electron acceptor. In contrast, in denatured hairpins and hairpins possessing neighboring G:G base pairs the stilbene diether linkers undergo efficient photoisomerization.
Original language | English (US) |
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Pages (from-to) | 12165-12173 |
Number of pages | 9 |
Journal | Journal of the American Chemical Society |
Volume | 124 |
Issue number | 41 |
DOIs | |
State | Published - Oct 16 2002 |
ASJC Scopus subject areas
- Catalysis
- Chemistry(all)
- Biochemistry
- Colloid and Surface Chemistry