Oligonucleotide Analogues with Integrated Bases and Backbones. Part 19.

The AsUdinucleosides 1and 2form thermoreversible gels in organic solvents. The basis of the gelation is the formation of linear aggregates by base pairing following desolvation of the nucleobases. This is evidenced by the absence of gel formation by the C6deaminated analogue 3of 1, the correlation of gelation with the anticonformation, as preferred for 1, and the temperature, concentration, and timedependent CD spectra. The gels were also characterized by the minimum gelation concentration, the gel–sol transition melting temperature, and rheological properties. [ABSTRACT FROM AUTHOR]