Oligodeoxynucleotides containing 2'-fluoro-arabino-nucleotide and C-nucleotide.

Oligonucleotides containing 2'-fluoro-ara-pyrimidines and 1-methyl-2'-deoxy-psi-uridine were synthesized. The melting profiles show that the presence of FMAU has a large stabilizing effect on the duplex. Replacement of dT with FAU or psi-dT, or dC with FAC resulted in the formation of less stable duplexes. Temperature-dependent CD spectroscopy demonstrated that the structures of these oligomers are very similar to those of unmodified oligomers, however, these minor alterations in structure of dodecamers resulted in faster splitting by endonuclease EcoR1.