Synthesis of 6, 6'-Cyclo-5', 6'-dideoxy-1-(β-D-allofuranosyl)cytosine and Related Nucleosides : Nucleosides and Nucleotides.LXXXVIII)

Abstract

A new synthetic route to 6, 6'-cyclo-5', 6'-dideoxy-1-(β-D-allofuranosyl)-uracil, -cytosine, and -4-thiouracil is described. The method involves a base-catalyzed condensation of 2, 4-dimethoxy-6-methylpyrimidine and 1-O-methyl-2, 3-O-isopropylidene-β-D-ribopentofuranosyldialdehyde, followed by an intramolecular glycosylation, and derivatization of the base moiety. The relationship of the sign of the circular dichroism (CD) spectra of carbon-bridged cyclopyrimidine nucleosides to the glycosyl torsion angle is discussed.