Nucleic Acids Research, 1981, Vol. 9, No. 20 5423-5442
© 1981
CHEMISTRY |
Comparative structural analysis of cytidine, ethenocytidine, and their protonated salts. I. Crystal and molecular structure of ethenocytidine*
odzimierz Krzy
osiak+
+Institute of Bioorganic Chemistry, Polish Academy of Sciences ul. Noskowskiego 12/14, 61-704 Pozna
++Department of Crystallography, Institute of Chemistry, A.Mickiewicz University ul. Grunwaldzka 6, 60-780 Pozna
, Poland
Author to whom correspondence should be addressed
Received July 31, 1981.
The X-ray crystal and molecular structure of 3, N4 -ethenocytidine (
Cyd) has been solved and refined on counter data to R-0.038. A detailed discussion of the base electronic structure, molecular conformation and intermolecular interactions is the starting point for a comparative analysis of the series: Cyd,
Cyd, Cyd.HCl, and
Cyd.HCl. Protonation changes the base electronic structure and results in a completely different molecular conformation and intermolecular Interactions. Ethenobridging does not alter the molecular conformation but it also changes the intermolecular interactions.
*Some parts of this paper were prsented at the following meetings:
- Biological Implications of Protein-Nucleic Acid Interactions Pozna
-Dymaczewo, May 1980 - 3rd International Symposium of Crystal Organic Chemistry Pozna
-Kiekrz, September 1980 - 4th Round Table on Nucleosides, Nucleotides and their Biological Applications Antwerp, February 1981