CYTOSINE

PRODUCT IDENTIFICATION
CAS NO. 71-30-7

CYTOSINE
EINECS NO.

200-749-5
FORMULA C4H5N3O
MOL WT. 111.10

H.S. CODE

 2933.59

TOXICITY

  
SYNONYMS 4-Amino-2-hydroxypyrimidine; 2-Oxy-4-amino pyrimidine; Cyt;
4-Amino-2(1H)-Pyrimidinone;
SMILES

 

CLASSIFICATION

  

PHYSICAL AND CHEMICAL PROPERTIES

PHYSICAL STATE

white to off-white crystalline powder
MELTING POINT

330 C
BOILING POINT  
SPECIFIC GRAVITY  
SOLUBILITY IN WATER  
pH  
VAPOR DENSITY

 
AUTOIGNITION

 
NFPA RATINGS  

REFRACTIVE INDEX

  
FLASH POINT  
STABILITY

Stable under ordinary conditions

GENERAL DESCRIPTION & APPLICATIONS
Ribose is a pentose (five-carbon sugar) that is a component of the ribonucleic acid (RNA), where it alternates with phosphate groups to form the 'back-bone' of the RNA polymer and binds to nitrogenous bases. Ribose phosphates are components of the nucleotide coenzymes and are utilized by microorganisms in the synthesis of the amino acid histidine. Its close relative, deoxyribose, is a constituent of deoxyribonucleic acid (DNA), where it alternates with phosphate groups to form the 'back-bone' of the DNA polymer and binds to nitrogenous bases. The presence of deoxyribose instead of ribose is one difference between DNA and RNA. Ribose has one more oxygen atom in its molecule than deoxyribose. Ribose has a five member ring composed of four carbon atoms and one oxygen. Hydroxyl groups are attached to three of the carbons. The other carbon and a hydroxyl group are attached to one of the carbon atoms adjacent to the oxygen. In deoxyribose, the carbon furthest from the attached carbon is stripped of the oxygen atom in what would be a hydroxyl group in ribose. The sugar (ribose or deoxyribose) molecules in the nucleic acid are all oriented in the same direction. Their carbon atoms are numbered: the 5' carbon atom is always on the side of the sugar molecule that faces the leading end, while the 3' carbon atom always faces the tail end. Nucleotide is the structural unit of a nucleic acid. A nucleotide consists of either a nitrogenous heterocyclic base (purine or pyrimidine) , a pentose sugar (ribose or deoxyribose) and a phosphate group attached at the 5' position on the sugar. A nucleoside consists of only a pentose sugar linked to a purine or pyrimidine base, without a phosphate group. Purine bases are Adenine, Guanine and Hypoxanthine (examples of purine nucleosides are Adenosine, 2'-Deoxyadenosine, Guanosine, 2'-Deoxyguanosine, Inosine, 2'-Deoxyinosine). Pyrimidine bases are Cytosine, Thymine, and Uracil (examples of pyrimidine nucleosides are Cytidine, 2'-Deoxyguanosine, 5-Methyluridine, 2'-Deoxy-5-Methyluridine, Uridine, 2'-Deoxyuridine). The nucleoside derivatives are involved in important functions in cellular metabolism and are used to synthesize enzyme inhibitors, antiviral agents, and anticancer agents.

 

Cytosine is a pyrimidine base, occurring condensed with ribose or deoxyribose to form the nucleosides cytidine and deoxycytidine in animal cells. It is a fundamental unit or base of nucleic acids. When N9 is linked to the C1 of ribose, cytosine forms a pyrimidine nucleoside called cytidines which are phosphorylated with from one to three phosphoric acid groups to form the three nucleotides; cytidine monophosphate (CMP), cytidine diphosphate (CDP), and cytidine triphosphate (TTP) respectively.  When N1 is linked to the C1 of deoxy ribose, deoxy nucleosides and nucleotides are formed from cytosine and deoxyribose; deoxycytidine monophosphate (dCMP), deoxycytidine diphosphate (dCDP),  deoxycytidine triphosphate (dCTP). CTP is the source of the cytidine in RNA (ribonucleic acid) and deoxycytidine triphosphate (dCTP) is the source of the deoxycytidine in DNA (deoxyribonucleic acid). CTP is involved in the formation of adenosine triphosphate (ATP) as a donator of phosphate groups to adenosine diphosphate (ADP).
  • Cytidine Monophosphate (CMP, Cytidylic Acid; ): a nucleotide, the 5'-phosphate of cytidine, acting as a carrier of N-acetylneuraminic acid in glycoprotein synthesis.
  • Cytidine Diphosphate (CDP): a nucleotide, the 5'-pyrophosphate of cytidine, acting as a carrier of choline and ethanolamine in the phospholipid synthesis.
  • Cytidine Triphosphate (CTP): a nucleotide, the 5'-triphosphate of cytidine; precursor in the synthesis of ribonucleic acid and of CDP- and CMP-linked compounds.
  • Deoxycytidine Monophosphate (dCMP): a nucleotide, the 5'-phosphate of deoxycytidine (deoxy-, also called desoxy, is a prefix for the designation of compounds which contain one less atom of oxygen than the reference substance).
  • Deoxycytidine Diphosphate (dCDP): a nucleotide, the 5'-pyrophosphate of deoxycytidine.
  • Deoxycytidine Triphosphate (dCTP): a nucleotide, the 5'-triphosphate of deoxycytidine; an precursor in the synthesis of DNA.
 

Chemically modified nucleotides substituted or attached by special chemical groups or elements are studied and used to inactivate the normal biological operation in the living organism and the function of important enzymes.
SALES SPECIFICATION

APPEARANCE

fine off-white crystalline powder
ASSAY

98.0 - 102.0 %

HEAVY METALS

10ppm max

LOSS ON DRYING

3.0% max

MELTING POINT

 > 300 C
TRANSPORTATION
PACKING
 
HAZARD CLASS  
UN NO.  
OTHER INFORMATION
Hazard Symbols: n/a, Risk Phrases: 36/37/38, Safety Phrases: 26-36