[Chemical reactions in double helical nucleic acids. XIII. Directed introduction of acylphosphate internucleotide...

DNA duplex, containing an acylphosphate internucleotide bond in a predetermined position of the sugar-phosphate backbone, was synthesized. The synthesis was carried out by condensing on the complementary matrix two heptanucleotides, one of which possessed at the 3'-end a glycine residue, connected with the oligonucleotide by the phosphoramide bond, whereas the 5'-end phosphate group of the other was activated with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDAC). The yield of the oligonucleotide with an acylphosphate bond was 24%. The stability and chemical properties of the synthesized compound were studied in comparison with analogous oligonucleotide containing a substituted pyrophosphate internucleotide bond. The former was shown to be an effective acylating agent in the aqueous medium in contrast to the latter which is a phosphorylating agent.