Abstract: An improved method for the preparation of acyclic nucleotide analogues comprises first condensing a cyclic carbonate with a purine or pyrimidine base and then reacting the alkylated base with an activated phosphonate. Novel cyclic carbonates are employed to yield the desired phosphonylmethoxyalkyl nucleotide analogues.

Abstract: Novel oligonucleotides analogs and nucleoside analogs as well as methods for their synthesis are described. The oligonucleotides are useful in diagnostic and therapeutic applications. The oligonucleotides are stable to nuclease degradation.

Abstract: An improved method for the preparation of acyclic nucleotide analogues comprises first condensing a cyclic carbonate with a purine or pyrimidine base and then reacting the alkylated base with an activated phosphonate. Novel cyclic carbonates are employed to yield the desired phosphonylmethoxyalkyl nucleotide analogues.

Abstract: Pyridinone or pyrimidinone nucleoside bases containing fused aromatic polycyclic rings are provided. These polycyclic nucleosides are incorporated into oligonucleotides and hybridized to complementary nucleic acid. Fluorescence spectroscopy and thermal denaturation profiles provided evidence that the polycyclic base is intercalated into the resulting duplex. The fused polycyclic ring systems optionally are substituted with reactive species which inactivate complementary nucleic acids. The oligonucleotides of this invention are useful as improved probes, diagnostic reagents, or for cleaving or derivatizing predetermined domains within nucleic acids.