D. Suck, W. Saenger, J. Hobbs
Jan 31, 1972
Citations
0
Influential Citations
12
Citations
Journal
Biochimica et biophysica acta
Abstract
Abstract The molecular and crystal structure of 2′-chloro-2′-deoxyuridine as determined from three-dimensional X-ray data is reported. The title compound crystallized from water in the form of colourless needles in the orthorhombic space group P212121 with cell constants a = 12.569 A , b = 4.830 A , c = 17.409 A and z = 4. The structure was solved by direct methods and refined to an agreement index R = 0.036. The conformational parameters of 2′-chloro-2′-deoxyuridine in the crystalline state are similar to those found in other pyrimidine nucleoside structures: the orientation of the base with respect to the sugar is anti, and the conformation about the C(4′)-C(5′) bond is gauche,gauche. The 2′-chloro-2′-deoxyribose is puckered with C(2′)-endo and despite the chloro substitution shows no significant differences in bond lengths, bond angles or torsional angles in comparison with the average values for unmodified ribose residues in the same C-2′-endo conformation. This finding is discussed with respect to the properties of poly-2′-chloro-2′-deoxyuridylic acid and with respect to previous NMR investigations of 2′-chloro-2′-deoxyribose nucleosides.