5-Nitrouridine-monohydrate: crystal structure and conformation.
AUTOR(ES)
Egert, E
RESUMO
The crystal structure of 5-nitrouridine was determined by X-ray analysis. The pyrimidine ring is slightly non-planar, showing a shallow boat conformation. The nitro group has no influence on the C4 - O4 bond length as compared to uridine. The ribose shows the C3'-endo conformation and the base is in the anti orientation to the sugar with a torsion angle of 25.6 degrees. This conformation is stabilized by a hydrogen bond from the base to the ribosyl moiety (H6 ... 05'). Stacking interactions between neighboring bases are almost negligible in the crystal. A water molecule is involved in a bifurcated donating hydrogen bond to 04 and to 052 of the nitro group of the one base and an accepting bond from the H3 of the other base. Two more hydrogen bonds are formed between the water molecule and the ribose. The structural aspects of 5-nitrouridine are discussed with respect to the special stacking features found for 5-nitro-1-(beta-D-ribosyluronic acid)-uracil monohydrate in the crystal (1).
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=342495Documentos Relacionados
- Crystal structure of the self-complementary 5'-purine start decamer d(GCGCGCGCGC) in the Z-DNA conformation. I.
- Crystal structure of the self-complementary 5'-purine start decamer d(GCACGCGTGC) in the A-DNA conformation. II.
- Crystal structure of an oligonucleotide duplex containing G.G base pairs: influence of mispairing on DNA backbone conformation.
- The crystal and molecular structure of 2'-deoxy-2'-fluoroinosine monohydrate.
- Crystal structure and molecular structure of mefloquine methylsulfonate monohydrate: implications for a malaria receptor.