The molecular and crystal structure of 5,6-dihydro-2-thiouridine, C9H14N2O5S

Abstract

5,6-Dihydro-2-thiouridine crystallizes in the space group P2~ with a= 15-330, b=7.517, c=5.070 A,, fl = 107.89 °, Z= 2. The structure was solved by direct methods and refined by the full-matrix least-squares technique to R 0.098. Because of the saturated C(5)-C(6) bond, the nucleobase is not planar. The ribose moiety has C(3')-endo conformation and the nucleoside molecule exhibits the usual anti conformation. The thiouridine molecules are connected by hydrogen bonds between sugar-sugar and base-base residues to form a three-dimensional network. There is no base stacking.

Crystal and molecular structures of 4-aryl-1,4-dihydropyrimidines: Novel calcium channel antagonists

“…The bond lengths and angles about the molecular framework common to the three structures are similar. The values of these parameters also agree with those reported for other 1,4-dihydropyrimidine calcium channel antagonists and related compounds [17][18][19][20][21][22]. Because of conjugation of the dihydropyrimidine ring, the bond lengths N1--C6 and N5--C6 are shorter than N1--C2 and N5--C4.…”