| Abstract: | A series of oligomer model compounds of polyethyleneimine derivatives with pendant adenine bases were prepared by the reaction of a carboxyethyl derivative of adenine with oligomeric amines, using an activated ester method. To evaluate the intramolecular interaction between pendant adenine bases in these compounds, ultraviolet spectra at various pH regions were measured. Ultraviolet hypochromicities and pKa values depended linearly on the chain length of the oligomers. The results showed that the intramolecular interactions of adenine bases were realized less in their protonated than neutral forms. |
