Category: 608-34-4

Kurinovich, Mary Ann published the artcileThe Acidity of Uracil from the Gas Phase to Solution: The Coalescence of the N1 and N3 Sites and Implications for Biological Glycosylation, Category: pyrimidines, the publication is Journal of the American Chemical Society (2000), 122(26), 6258-6262, database is CAplus.

The gas-phase acidities of the N1 and N3 sites of uracil have been bracketed to provide an understanding of the intrinsic reactivity of this nucleic base. The experiments indicate that in the gas phase, the N3 site is far less acidic (ΔH_acid = 347 ± 4 kcal mol^-1) than the N1 site (ΔH_acid = 333 ± 4 kcal mol^-1), in direct contrast to in solution, where the two sites are so close in acidity as to be unresolvable. This intrinsic difference and the coalescence in solution is interpreted through gas-phase and dielec.-medium calculations The results point to a possible chem. reason that N1 is the preferred glycosylation site in nature: nature may simply take advantage of the differential N1 and N3 acidities in a nonpolar environment to achieve selectivity.

Journal of the American Chemical Society published new progress about 608-34-4. 608-34-4 belongs to pyrimidines, auxiliary class Pyrimidine,Amide, name is 3-Methylpyrimidine-2,4(1H,3H)-dione, and the molecular formula is C5H6N2O2, Category: pyrimidines.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Kurinovich, Mary Ann published the artcileThe acidity of uracil and uracil analogs in the gas phase: four surprisingly acidic sites and biological implications, Recommanded Product: 3-Methylpyrimidine-2,4(1H,3H)-dione, the publication is Journal of the American Society for Mass Spectrometry (2002), 13(8), 985-995, database is CAplus and MEDLINE.

The gas phase acidities of a series of uracil derivatives (1-methyluracil, 3-methyluracil, 6-methyluracil, 5,6-dimethyluracil, and 1,3-dimethyluracil) have been bracketed to provide an understanding of the intrinsic reactivity of uracil. The experiments indicate that in the gas phase, uracil has four sites more acidic than water. Among the uracil analogs, the N1-H sites have ΔH_acid values of 331-333 kcal mol^-1; the acidity of the N3 sites fall between 347-352 kcal mol^-1. The vinylic C6 in 1-methyluracil and 3-methyluracil brackets to 363 kcal mol^-1, and 369 kcal mol^-1 in 1,3-dimethyluracil; the C5 of 1,3-dimethyluracil brackets to 384 kcal mol^-1. Calculations conducted at B3LYP/6-31+G are in agreement with the exptl. values. The bracketing of several of these sites involved utilization of an FTMS protocol to measure the less acidic site in a mol. that has more than one acidic site, establishing the generality of this method. In mols. with multiple acidic sites, only the two most acidic sites were bracketable, which is attributable to a kinetic effect. The measured acidities are in direct contrast to solution acidities, where the two most acidic sites of uracil (N1 and N3) are cannot be differentiated. The vinylic C6 site is also particularly acidic, compared to acrolein and pyridine. The biol. implications of these results particularly with respect to enzymes for which uracil is a substrate are discussed.

Journal of the American Society for Mass Spectrometry published new progress about 608-34-4. 608-34-4 belongs to pyrimidines, auxiliary class Pyrimidine,Amide, name is 3-Methylpyrimidine-2,4(1H,3H)-dione, and the molecular formula is C5H6N2O2, Recommanded Product: 3-Methylpyrimidine-2,4(1H,3H)-dione.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Zielenkiewicz, Wojciech published the artcileHeat Capacities of Uracil, Thymine, and Its Alkylated, Cyclooligomethylenated, and Halogenated Derivatives by Differential Calorimetry, Recommanded Product: 3-Methylpyrimidine-2,4(1H,3H)-dione, the publication is Journal of Chemical & Engineering Data (2007), 52(1), 93-97, database is CAplus.

The molar heat capacity (C_p) of solid uracil, its alkylated and halogenated derivatives, and cyclooligomethylenouracils in the temperature range of (298.15 to 343.15) K by a differential scanning calorimeter (SETARAM TG-DSC 111) were determined It was demonstrated that the C_p value increases by increasing the number of methylene groups attached to the diketo-pyrimidine ring. The correlations C_p = f(T) are given. The contributions of C-CH₃, N-CH₃, and C-NO₂ groups as well as F, Cl, Br, and I atoms in the value of C_p for the temperature of 298.15 K are presented. The Chickos method for calculation of C_p values is discussed.

Journal of Chemical & Engineering Data published new progress about 608-34-4. 608-34-4 belongs to pyrimidines, auxiliary class Pyrimidine,Amide, name is 3-Methylpyrimidine-2,4(1H,3H)-dione, and the molecular formula is C10H10O3, Recommanded Product: 3-Methylpyrimidine-2,4(1H,3H)-dione.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Novak, Igor published the artcileElectronic structure and biological activity of nucleobases, Formula: C5H6N2O2, the publication is Spectrochimica Acta, Part A: Molecular and Biomolecular Spectroscopy (2005), 61A(11-12), 2771-2774, database is CAplus and MEDLINE.

HeI and HeII photoelectron spectra of 6-chloro-1,3-dimethyluracil have been measured. The assignment of the spectrum was made by comparison with photoelectron spectra of related compounds and by high-level OVGF calculations The electronic structure changes in substituted nucleobases are discussed on the basis of photoelectron spectroscopic data. The electronic structure data are compared with structure-activity relationships regarding enzyme inhibition and complex formation. The electronic structure data give some insight into the nature of binding between nucleobases’ derivatives and different enzymes whose activity they inhibit.

Spectrochimica Acta, Part A: Molecular and Biomolecular Spectroscopy published new progress about 608-34-4. 608-34-4 belongs to pyrimidines, auxiliary class Pyrimidine,Amide, name is 3-Methylpyrimidine-2,4(1H,3H)-dione, and the molecular formula is C5H6N2O2, Formula: C5H6N2O2.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Samijlenko, S. P. published the artcileSpecific interactions of deprotonated carboxylic group with uracil and thymine provoke diketo → keto-enol tautomeric transition in bases., Related Products of pyrimidines, the publication is Ukrains’kii Biokhimichnii Zhurnal (2001), 73(4), 128-131, database is CAplus.

The H¹ NMR and MNDO/H calculation data combined indicate the uracil and thymine tautomeric transitions from the ground diketo tautomeric state to the high-energy keto-enol one stimulated by specific interaction with carboxylate ion in anhydrous DMSO, which is blocked by base methylation at the 1 or 3 positions.

Ukrains’kii Biokhimichnii Zhurnal published new progress about 608-34-4. 608-34-4 belongs to pyrimidines, auxiliary class Pyrimidine,Amide, name is 3-Methylpyrimidine-2,4(1H,3H)-dione, and the molecular formula is C5H6N2O2, Related Products of pyrimidines.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Stepanyugin, A. V. published the artcileUV spectra of pyrimidine bases and nucleosides in the context of methyl substitution and interaction with amino acid carboxylic group, Computed Properties of 608-34-4, the publication is Biopolimeri i Klitina (2003), 19(1), 43-63, database is CAplus.

UV spectra of pyrimidine nucleotide bases, nucleosides, a number of their derivatives and analogs were investigated in anhydrous DMSO. Effects of interaction with neutral and deprotonated carboxylic group of amino acids on the UV spectra were traced. It was established that methylation of pyrimidine bases at the positions 1 and S leads to the 5-12 nm bathochromic shift of the absorption bands. The majority of the Cyt derivatives excluding m³ Cyt and isoCyt were shown to interact specifically with neutral carboxylic group. Interactions with deprotonated carboxylic group is characteristic of Ura, Thy and their derivatives, except chx¹Ura, s²Ura and dU. The conclusion was drawn that substitution at the positions 1 and 5 is accompanied by a decrease of a complex formation ability with the both forms of carboxylic groups, but substitution at the position 5 strengthens interaction with neutral carboxylic group but decreases interaction with carboxylate-ion. Biol. significance of the results obtained is discussed.

Biopolimeri i Klitina published new progress about 608-34-4. 608-34-4 belongs to pyrimidines, auxiliary class Pyrimidine,Amide, name is 3-Methylpyrimidine-2,4(1H,3H)-dione, and the molecular formula is C4H12ClNO, Computed Properties of 608-34-4.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Bojarska, Elzbieta published the artcileNovel electrochemically derived dimers of methylated uracils, Category: pyrimidines, the publication is Zeitschrift fuer Naturforschung, B: Chemical Sciences (1997), 52(6), 742-748, database is CAplus.

Electrolysis of HOAc/NaOAc solutions of N-methylated uracils results in the formation of 5-substituted Me and acetoxy derivatives Electrolysis of CF₃CO₂H/CF₃CO₂K solutions of N(1)- and N(3)-methylated uracils provided, besides 5-trifluoromethyl derivatives, novel N-C uracil dimers. Decomposition kinetics of the latter in NaOH are reported. In case of 1,3-dimethyluracil in CF₃CO₂H, N(1)-demethylation was also observed

Zeitschrift fuer Naturforschung, B: Chemical Sciences published new progress about 608-34-4. 608-34-4 belongs to pyrimidines, auxiliary class Pyrimidine,Amide, name is 3-Methylpyrimidine-2,4(1H,3H)-dione, and the molecular formula is C5H6N2O2, Category: pyrimidines.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Iltzsch, Max H. published the artcileStructure-activity relationship of nucleobase ligands of uridine phosphorylase from Toxoplasma gondii, Formula: C5H6N2O2, the publication is Biochemical Pharmacology (1993), 46(10), 1849-58, database is CAplus and MEDLINE.

Seventy-nine nucleobase analogs were evaluated as potential inhibitors of T. gondii uridine phosphorylase (UrdPase), and the apparent K_i (appK_i) values for these compounds were determined Based on the inhibition data, a structure-activity relationship for the binding of nucleobase analogs to the enzyme was formulated, using uracil as a reference compound Two compounds were identified as very potent inhibitors of T. gondii UrdPase: 5-benzyloxybenzylbarbituric acid and 5-benzyloxybenzyluracil, which had appK_i values of 0.32 and 2.5 μM, resp. A comparison of the results from the present study with those from similar studies on mammalian UrdPase and thymidine phosphorylase (dThdPase) revealed that there are both similarities and differences between the catalytic site of T. gondii UrdPase and the catalytic sites of the mammalian enzymes with respect to binding of uracil analogs. One compound, 6-benzyl-2-thiouracil, was identified as a potent, specific inhibitor (appK_i = 14 μM) of T. gondii UrdPase, relative to mammalian UrdPase and dThdPase.

Biochemical Pharmacology published new progress about 608-34-4. 608-34-4 belongs to pyrimidines, auxiliary class Pyrimidine,Amide, name is 3-Methylpyrimidine-2,4(1H,3H)-dione, and the molecular formula is C5H6N2O2, Formula: C5H6N2O2.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Almeida, D. published the artcileN-site de-methylation in pyrimidine bases as studied by low energy electrons and ab initio calculations, Computed Properties of 608-34-4, the publication is Physical Chemistry Chemical Physics (2013), 15(27), 11431-11440, database is CAplus and MEDLINE.

Electron transfer and dissociative electron attachment to 3-methyluracil (3meU) and 1-methylthymine (1meT) yielding anion formation were studied in atom-mol. collision and electron attachment experiments, resp. The former was studied in the collision energy range 14-100 eV whereas the latter in the 0-15 eV incident electron energy range. In the present studies, emphasis is given to the reaction channel resulting in the loss of the Me group from the N-sites with the extra charge located on the pyrimidine ring. This particular reaction channel has neither been approached in the context of dissociative electron attachment nor in atom-mol. collisions yet. Quantum chem. calculations were performed to provide some insight into the dissociation mechanism involved along the N-CH₃ bond reaction coordinate. The calculations provide support to the threshold value derived from the electron transfer measurements, allowing for a better understanding of the role of the potassium cation as a stabilizing agent in the collision complex. The present comparative study gives insight into the dynamics of the decaying transient anion and more precisely into the competition between dissociation and auto-detachment.

Physical Chemistry Chemical Physics published new progress about 608-34-4. 608-34-4 belongs to pyrimidines, auxiliary class Pyrimidine,Amide, name is 3-Methylpyrimidine-2,4(1H,3H)-dione, and the molecular formula is C5H6N2O2, Computed Properties of 608-34-4.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Sako, Magoichi published the artcileReductive Cleavage of Heteroaryl C-Halogen Bonds by Iodotrimethylsilane. Facile and Regioselective Dechlorination of Antibiotic Pyrrolnitrin, Product Details of C5H6N2O2, the publication is Journal of Organic Chemistry (2001), 66(10), 3610-3612, database is CAplus and MEDLINE.

The authors describe regioselective dechlorination of antibiotic pyrrolnitrin (I) via reductive cleavage of heteroaryl C-halogen bonds by iodotrimethylsilane. Reductive cleavage of the C-halo bond proceeds smoothly, efficiently and chemoselectively even under mild conditions with halo uridines and pyrimidines.

Journal of Organic Chemistry published new progress about 608-34-4. 608-34-4 belongs to pyrimidines, auxiliary class Pyrimidine,Amide, name is 3-Methylpyrimidine-2,4(1H,3H)-dione, and the molecular formula is C5H6N2O2, Product Details of C5H6N2O2.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia