Title: Cytidine
CAS Registry Number: 65-46-3
Additional Names: 4-Amino-1-b-D-ribofuranosyl-2-(1H)-pyrimidinone; cytosine riboside; 1-b-D-ribofuranosylcytosine
Molecular Formula: C9H13N3O5
Molecular Weight: 243.22
Percent Composition: C 44.44%, H 5.39%, N 17.28%, O 32.89%
Literature References: Constituent of nucleic acids. Isoln from yeast nucleic acid: Levene, Jacobs, Ber. 43, 3154 (1910); Levene, La Forge, ibid. 45, 608 (1912). Sepn from other nucleosides by ion-exchange chromatography: Cohn in Chargaff-Davidson, The Nucleic Acids vol. I (New York, 1955) p 211. Synthesis: Howard et al., J. Chem. Soc. 1947, 1052. Crystal structure: Furberg et al., Acta Crystallogr. 18, 313 (1965). Review: Basic Principles in Nucleic Acid Chemistry vol. 1, P. O. P. Ts'o, Ed. (Academic Press, New York, 1974) passim.
Properties: Long needles from 90% ethanol, dec 220-230°. [a]D25 +31° (c = 0.7 in water). Freely sol in water, less sol in alcohol. pK (amino, cationic) 4.22; pK (sugar, anionic) 12.5. uv max (pH 8.2): 271 nm (e 9100); (pH 2.2): 280 nm (e 13400), Voet et al., Biopolymers 1, 193 (1963).
pKa: pK (amino, cationic) 4.22; pK (sugar, anionic) 12.5
Optical Rotation: [a]D25 +31° (c = 0.7 in water)
Absorption maximum: uv max (pH 8.2): 271 nm (e 9100); (pH 2.2): 280 nm (e 13400), Voet et al., Biopolymers 1, 193 (1963)
Derivative Type: Sulfate
Molecular Formula: (C9H13N3O5)2.H2SO4
Molecular Weight: 584.51
Percent Composition: C 36.99%, H 4.83%, N 14.38%, O 38.32%, S 5.49%
Properties: Long prismatic needles, mp 224-225° (dec with effervescence). [a]25589 +34°; [a]25546 +43°.
Melting point: mp 224-225° (dec with effervescence)
Optical Rotation: [a]25589 +34°; [a]25546 +43°
Cytisine Cytochalasins Cytochrome c Cytochromes P450 Cytohemin

CAS number 65-46-3 YesY
PubChem 6175
ChemSpider 5940 YesY
KEGG D07769 YesY
MeSH Cytidine
ChEBI CHEBI:17562 YesY
Jmol-3D images Image 1
Molecular formula C9H13N3O5
Molar mass 243.22 g mol−1
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Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Cytidine is a nucleoside molecule that is formed when cytosine is attached to a ribose ring (also known as a ribofuranose) via a β-N1-glycosidic bond. Cytidine is a component of RNA.

If cytosine is attached to a deoxyribose ring, it is known as a deoxycytidine.