Cyclic Cytidine 2',3'-Phosphate: Molecular Structure

Science  11 Sep 1970:
Vol. 169, Issue 3950, pp. 1097-1098
DOI: 10.1126/science.169.3950.1097


Monoclinic crystals of the sodium salt of cytidine 2',3'-phosphate contain two anions in the asymmetric unit. Both bases are in the syn conformation, and the nucleotides are stacked together into an antiparallel stranded ribbon with the bases 3.3 angstroms apart. One ribose ring is planar, and the other has oxygen-1' puckered toward carbon-5'. The phosphorus atoms in the five-membered ester rings are puckered toward the sugars. The conformations about the carbon-4'—carbon-5' bonds are gauche-trans and gauche-gauche.