156398-76-4

Basic information

• Product Name: 1,3-dimethyl-2,4-pyrimidinione
• Synonyms: 1,3-dimethyl-2,4-pyrimidinione
• CAS NO: 156398-76-4
• Molecular Formula: C6H8N2O2
• Molecular Weight: 140.14
• Mol File: 156398-76-4.mol

Chemical Properties

• Appearance: /
• CAS DataBase Reference: 1,3-dimethyl-2,4-pyrimidinione(CAS DataBase Reference)
• NIST Chemistry Reference: 1,3-dimethyl-2,4-pyrimidinione(156398-76-4)
• EPA Substance Registry System: 1,3-dimethyl-2,4-pyrimidinione(156398-76-4)

Safety Data

• Hazardous Substances Data: 156398-76-4(Hazardous Substances Data)

Upstream product

• 186581-53-3 diazomethane 
• 66-22-8 uracil 
• 3551-55-1 2,4-dimethoxypyrimidine 
• 6972-27-6 1,3-Dimethyl-6-chlorouracil 
• 7152-66-1 1-methyl-4-methoxy-2-oxo-1,2-dihydropyrimidine 
• 77-78-1 dimethyl sulfate 
• 120-72-9 indole 
• 4869-46-9 1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydro-pyrimidine-5-carbaldehyde 
• 141-90-2 2-thiouracil 
• 17237-74-0 (4aR*,4bS*,8aS*,8bR*)-1,3,6,8-tetramethylhexahydrocyclobuta[1,2-d:4,3-d']dipyrimidine-2,4,5,7(3H,6H)-tetraone 
• 49785-67-3 1,3-dimethyl-4-thiouracil 
• 109-80-8 1.3-propanedithiol 
• 7033-39-8 5-bromo-1,3-dimethyluracil 
• 91-16-7 1,2-dimethoxybenzene 

Downstream Products

• 104139-64-2 5-(1-Benzyl-2,5-dioxo-2,5-dihydro-1H-pyrrol-3-yl)-1,3-dimethyl-1H-pyrimidine-2,4-dione 
• 84174-99-2 4-[3-Chloro-4-(1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydro-pyrimidin-5-yl)-2,5-dioxo-2,5-dihydro-pyrrol-1-yl]-benzoic acid ethyl ester 
• 124851-78-1 5-cyclohexyl-1,3-dimethyluracil 
• 32079-08-6 5-Acetoxymethyl-1,3-dimethyluracil 
• 129056-81-1 5-Carboxymethyl-1,3-dimethyluracil 
• 10211-36-6 3-phenyl-pyridine-2,6-diol 
• 10211-36-6 6-Hydroxy-5-phenyl-1H-pyridin-2-one 
• 4874-13-9 1,3-dimethyluracil 
• 1224944-43-7 sodium pyrazolo[1,5-a] pyrimidin-5-olate 
• 42542-99-4 1,3-dimethyl-6-phenyluracil 
• 55377-22-5 1,3-dimethyl-5-phenylpyrimidine-2,4(1H,3H)-dione 

Relevant articles and documents

A Possible Chain Reaction in Photosensitized Splitting of Pyrimidine Dimers by a Protonated, Oxidized Flavin

Pyrimidine dimer cycloreversion was photosensitized by protonated 2',3',4',5'-tetraacetylriboflavin (ac4rfH+), whereas the protonated flavin radical (ac4rfH2.+) failed to sensitize detectable dimer splitting.In acetonitrile containing 0.075percent perchloric acid, the ac4rf absorption bands at 375 nm and 445 nm are replaced by a new band at 390 nm due to ac4rfH+.Irradiation of ac4rfH+ in the presence of cis,syn- or trans,syn-1,3-dimethyluracil dimer resulted in efficient cycloreversion to 1,3-dimethyluracil, probably induced by electron abstraction from the dimer by ac4rfH+ to produce the dimer radical cation.The quantum yields of splitting were large (Φspl = 0.35 and 1.5 for cis,syn and trans,syn isomers, respectively, at = 1.2 mM).Splitting quantum yields increased with dimer concentration in a quadratic fashion.These results are consistent with the occurance of a chain reaction propagated by monomer.+ + dimer -> monomer + dimer.+ in the case of the dimethyluracil dimers.The fluorescence of the protonated flavin (λem = 507 nm) was found to be quenched by the dimers.In the presence of small amounts of added water, however, both the fluorescence quenching and splitting were abolished.Two cis,syn dimers in which the N(1)- and N(1')-atoms were tethered via a trimethylene bridge exhibited quantum yields of approximately 0.02 at the above dimer concentration.A compound in which ac4rf is covalently bound to a pyrimidine dimer was also found to undergo splitting in acidified acetonitrile (Φ = 0.03).These values are more than 1 order of magnitude greater than those reported for unprotonated flavins.

Photochemical behaviour of 5-perfluoroalkenyl uracils

Phototransformations of derivatives of 5-fluoroalkenyl uracils depend strongly on the fluorinated substituents. 1,3-Dimethyl-5-trifluorovinyluracil when irradiated in water with UV light (λ>300nm) gives 1,3-dimethyl-(5,6-dihydrourac-6-yl)-difluoroacetic a

Relative Enthalpies of 1,3-Dimethyl-2,4-pyrimidinedione, 2,4-Dimethoxypyrimidine, and 4-Methoxy-1-methyl-2-pyrimidinone: Estimation of the Relative Stabilities of Two Protomers of Uracil

The relative gas-phase enthalpies of 1,3-dimethyl-2,4-pyrimidinedione (5), 2,4-dimethoxypyrimidine (6), and 4-methoxy-1-methyl-2-pyrimidinone (7) have been determined by calorimetric measurements of the heats of isomerisation in the liquid and estimates of the heats of vaporization.The values of ΔHg0 are -38 +/- 4.7 kcal/mol for 5-6 and -27 +/- 4.1 kcal/mol for 5-7.These results show the relative energies of the amide-imidate functions in a heteroaromatic system can be quite different.The relative enthalpies for 5,6, and 7 are used to provide estimates of the enthalpy differences between uracil (11) and 2,4-dihydroxypyrimidine (16) as -22 +/- 10 kcal/mol and between 11 and 4-hydroxy-2-pyrimidinone (13) as -19 +/- 6 kcal/mol.Although the errors are large, this is the first experimentally based estimate for the relative stabilities of these tautomers in the vapor.It is suggested that the relative energies of uracil protomers in soluion are effected more by hydrogen bonding than by reaction field effects.

13C kinetic isotope effects and the mechanism of the uncatalyzed decarboxylation of orotic acid

A complete set of 13C kinetic isotope effects were determined for the thermal decarboxylation of 1,3-dimethylorotic acid and compared with theoretically predicted isotope effects for decarboxylation via either O-2 or O-4 protonated pathways. The best correspondence of experimental and calculated isotope effects is found for the O-4 protonated mechanism. This observation and the calculated reaction barriers support the previously predicted preference for this pathway. The preference for the O-4 protonated mechanism is found to result from a general predilection for O-4 protonation over O-2 protonation in the orotate/uracil series, and no significant extra stability appears associated with the formation of a formal carbene in the O- 4 protonated decarboxylation. The carboxylate isotope effect for the uncatalyzed reaction is much smaller than the enzyme-catalyzed isotope effect recently reported, suggesting some divergence between uncatalyzed and enzyme- catalyzed mechanisms.

A multi-step photoreaction of 5-formyl-1,3-dimethyluracil with indole in the solid state

Irradiation of the mixed crystals between 5-formyl-1,3-dimethyluracil (1) and indole (2) gave 5-(bis-1-indolyl)methyl-1,3-dimethyluracil (3), whereas 1,3-dimethyluracil was the sole product in the photolysis of 1 and 2 in solution.

Carbanions from decarboxylation of orotate analogs: Stability and mechanistic implications

The pKa's of the 6-CH groups of 1,3-dimethyluracil, N-methyl-2-pyridone, and N-methyl-4-pyridone were determined through their reactions with bases derived from carbon acids with known pKa and the reactions of their corresponding carbanions with the carbon acids. No correlation between the stability of the carbanions and the rate of decarboxylation of corresponding carboxylic acids was found.

A FACILE PHOTOCHEMICAL ROUTE TO C-5 AND C-6 ALLYL-SUBSTITUTED URACIL NUCLEOSIDES

Irradiation of 5-iodouridine or 6-iodo-1,3-dimethyluracil in aq. acetonitrile in the presence of allyltrimethylsilane provided the corresponding 5- or 6-allylated product.

Decarboxylation of orotic acid analogues: Comparison of solution and gas-phase reactivity

The decarboxylation of orotic acid and analogues have been investigated as a model for enzymatic decarboxylation catalyzed by orotidine-5′-monophosphate decarboxylase (ODCase). The rate of decarboxylation of 1-methyl-4-pyridone-2-carboxylic acid in solution has been reported to be three orders of magnitude greater than those of 1,3-dimethylorotic acid and 1-methyl-2-pyridone-6-carboxylic acid in solution. Here, the gas-phase decarboxylation of the three corresponding carboxylates were investigated. The carboxylate of 1,3-dimethylorotic acid decarboxylates at a faster rate and thus the relative rates of decarboxylation are different from those observed in solution. The relative rates of decarboxylation correlate well with the stability of the corresponding carbanions and the calculated activation energies for gas-phase decarboxylation. Therefore, the reactions in the gas phase seem to go through the direct decarboxylation mechanism whereas the reactions in solution likely go through zwitterionic intermediates as previously proposed.

Photochemistry of Flavins in Micelles: Specific Effects of Anionic Surfactants on the Monomerization of Thymine Cyclobutane Dimers Photosensitized by Tetra-O-acyl Riboflavins

It was found that tetra-o-acyl riboflavins efficiently photosensitize the monomerization of the cis, syn-cyclobutane dimers of 1,3-dimethylthymine and 1,3-dimethyluracil in aqueous solution in the presence of such anionic surfactants as sodium dodecyl sulfate and sodium hexadecyl sulfate at concentrations higher than their critical micelle concentration, while little monomerization of the dimers was photosensitized by the flavins in the absence of the surfactants and even in the presence of cationic and nonionic surfactants.

Mechanism of decarboxylation of 1,3-dimethylorotic acid revisited: Trapping of the reaction intermediate

The decarboxylation of 1,3-dimethylorotic acid was investigated to study the nature of the reaction intermediate. 6-Benzyl-1,3-dimethyluracil was isolated when the decarboxylation was carried out in benzyl bromide, indicating the involvement of a carbon-6 centered nucleophilic intermediate in the reaction pathway.