Article

Parallel-stranded duplexes and quartet assemblies formed by oligonucleotides containing isoguanine.

Laboratorium für Organische und Bioorganische Chemie, Institut für Chemie, Universität Osnabrück, Germany.
Nucleic Acids Symposium Series 02/1997;
Source: PubMed

ABSTRACT Oligonucleotides with isoguanine-cytosine base pairs form duplexes with parallel chain orientation. This strong base pair dictates the strand polarity when additional dA-dT or N7Ad-dT pairs are present. The same is observed for the isocytosine-guanine pair. Quartet structures are built by the self-assembly of oligonucleotides containing short runs of isoguanine or 7-deazaisoguanine. New base pairs between isoguanine or guanine and 5-aza-7-deazaguanine are presented.

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