Structure and Base Pairing Properties of a Replicable Nonpolar Isostere for Deoxyadenosine.

ABSTRACT: We report the synthesis, structure, and pairing properties in DNA of an isostere for deoxyadenosine which lacks all hydrogen-bonding functionality on the Watson-Crick pairing edge. A deoxyribo-nucleoside derivative of 4-methylbenzimidazole (1), which was recently shown to be inserted into DNA by Klenow DNA polymerase (Morales, J. C.; Kool, E. T. Nature Struct. Biol.1998, 5, 950), is prepared from 1-chloro-2-deoxy-3,5-bis-O-p-toluoyl-α-D-erythro-pentofuranose. The X-ray crystal structure of the nucleoside confirms that the compound is a close steric match for deoxyadenosine (2), although the methylbenzimidazole base is in the syn glycosidic orientation in the crystal. In D(2)O solution, 1H NMR studies show that 1 and 2 have similar (60% vs 70% S) sugar conformations and anti glycosidic orie

SUBMITTER: Guckian KM 

PROVIDER: S-EPMC2939748 | biostudies-literature | 1998

REPOSITORIES: biostudies-literature