20545-68-0

Basic information

• Product Name: 5,5'-Dimethyl-4,4'-bipyrimidine-2,2',6(1H,1'H,3H)-trione
• Synonyms: 5,5'-Dimethyl-4,4'-bipyrimidine-2,2',6(1H,1'H,3H)-trione
• CAS NO: 20545-68-0
• Molecular Formula: C10H10N4O3
• Molecular Weight: 234.2114
• Mol File: 20545-68-0.mol
• Article Data: 3

Chemical Properties

• Appearance: /
• CAS DataBase Reference: 5,5'-Dimethyl-4,4'-bipyrimidine-2,2',6(1H,1'H,3H)-trione(CAS DataBase Reference)
• NIST Chemistry Reference: 5,5'-Dimethyl-4,4'-bipyrimidine-2,2',6(1H,1'H,3H)-trione(20545-68-0)
• EPA Substance Registry System: 5,5'-Dimethyl-4,4'-bipyrimidine-2,2',6(1H,1'H,3H)-trione(20545-68-0)

Safety Data

• Hazardous Substances Data: 20545-68-0(Hazardous Substances Data)

Upstream product

• 50-89-5 thymidine 
• 41398-83-8 C₂₀H₂₈N₄O₁₀ 
• 87367-14-4 thymidilyl(3'-5')thymidine 
• 20545-93-1 (5-hydroxy-5,6-dihydrothyminyl)-(6-4')(5'-methyl-1',2'-dihydropyrimidin-2'-one) 

Relevant articles and documents

The (5-4) and (6-4) adducts of 1-methylthymine and their Dewar valence isomers

Previous studies of the photochemical reaction of 1-methylthymine (MeT) in frozen aqueous solution have indicated that four cyclobutane type dimers are formed. We have restudied this system and have found that, in addition to cyclobutane dimers, both a (5-4) adduct and a (6-4) adduct of MeT are formed in significant amounts. Upon standing in aqueous solution, the (5-4) adduct is susceptible to reaction to form an isomeric form of the parent adduct, possibly via ring-opening and closure reactions at C-6 of the saturated pyrimidine ring component of the adduct. Irradiation of each of these three adducts with UVB light produces a pair of Dewar-type adducts. The nine products were individually characterized by mass spectrometry, proton NMR spectroscopy and UV spectroscopy. A less comprehensive study showed that irradiation of thymidine in frozen aqueous solution produces a diastereomeric pair of (5-4) adducts, along with the previously known diastereomeric pair of (6-4) adducts. Irradiation of 1-methylthymine (center) at 254 nm in frozen aqueous solution produces, in addition to cyclobutane dimers, both a (6-4) adduct (left) and a (5-4) adduct (right). The initially formed (5-4) adduct is unstable toward thermal conversion to another isomeric (5-4) adduct. Irradiation of each of these adducts in fluid solution with UVB results in the formation of two Dewar valence isomers. Similarly, irradiation of thymidine, frozen in ice at -78.5°C, produces a diastereomeric pair of (5-4) adducts, along with a corresponding pair of previously known (6-4) adducts.

Thymine-thymine adduct as a photoproduct of thymine.

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