Synthesis and Properties of Hyaluronic Acid Conjugated Nucleic Acid Analogs—1: Synthesis of Deacetylhyaluronan and Introduction of Nucleic Acid Bases

The conjugation of nucleic acid base with hyaluronan was achieved by using the activated ester of pentachlorophenyl trichloroacetate. The conditions of de-N-acetylation of sodium hyaluronic acid were studied. In low concentrations of NaOH, the degree of deacetylation was 26%, while in 7.4N NaOH, the degree of deacetylation was 76% and the viscosity was 1.12 dL/g. Thymine and 5-fluorouracil bases were quantitatively conjugated to deacetylhyaluronan in 65% and 51%, respectively. The interaction of thymine hyaluronan conjugate with the complementary base of polyadenylate showed a small hypochromicity.