Tag: M.W=100-150

Itahara, Toshio published the artcilePreparation and NMR study of 7,7′-(α,ω-alkanediyl)bis[theophylline], 1,1′-(α,ω-alkanediyl)bis[theobromine], and 1,1′-(α,ω-alkanediyl)bis[3-methyluracil], Synthetic Route of 608-34-4, the publication is Bulletin of the Chemical Society of Japan (1994), 67(1), 203-9, database is CAplus.

The treatment of theophylline, theobromine, and 3-methyluracil with X(CH₂)_nX (X = Br or I, n = 1-12) in N,N-dimethylformamide containing sodium hydride gave the corresponding 7,7′-(α,ω-alkanediyl)-bis[theophylline], 1,1′-(α,ω-alkanediyl)bis[theobromine], and 1,1′-(α,ω-alkanediyl)bis[3-methyluracil]. The interaction of the theophylline, theobromine, and 3-methyluracil rings of these compounds was studied based on their ¹H NMR spectra, and stacking of the two purine rings of 7,7′-(α,ω-alkanediyl)bis[theophylline] was observed

Bulletin of the Chemical Society of Japan 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, Synthetic Route of 608-34-4.

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

Palafox, M. A. published the artcileThe hydration effect on the uracil frequencies: an experimental and quantum chemical study, Category: pyrimidines, the publication is Journal of Molecular Structure: THEOCHEM (2002), 69-92, database is CAplus.

This work describes the performance of different quantum chem. theor. methods in calculating the vibrational frequencies of uracil and some derivatives, and the effect of hydration on the uracil frequencies. The Raman spectra of polycrystalline uracil with different water contents are discussed. To correct the deficiency of the theor. quantum chem. methods, several procedures are described. Two of them are new. For these new procedures, scaling factors and scaling equations were determined at different levels. With them, a significant reduction in the error of the predicted frequencies was obtained over the 1-factor scaling standard procedure. A comparison of the cost/effective method and procedure of scaling was carried out on uracil mol. Scale factors transferred from uracil to related mols. provided an a priori prediction of fundamental frequencies and intensities, permitting several corrections to be proposed for earlier assignments.

Journal of Molecular Structure: THEOCHEM 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

Cowden, William B. published the artcilePyrimidine N-oxides. VI. The ionization constants of pyrimidine-2,4-diamine N-oxides, Formula: C4H6N4O, the publication is Australian Journal of Chemistry (1984), 37(6), 1195-201, database is CAplus.

The ionization constants of some pyrimidine-2,4-diamines and their N-oxides, including the drugs trimethoprim and minoxidil, are reported. The syntheses of several pyrimidine-2,4-diamine N-oxides are described.

Australian Journal of Chemistry published new progress about 74638-76-9. 74638-76-9 belongs to pyrimidines, auxiliary class Pyrimidine, name is 2,4-Diaminopyrimidine-3-oxide, and the molecular formula is C4H6N4O, Formula: C4H6N4O.

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

Dracinsky, Martin published the artcileMechanism of the Isotopic Exchange Reaction of the 5-H Hydrogen of Uracil Derivatives in Water and Nonprotic Solvents, Name: 3-Methylpyrimidine-2,4(1H,3H)-dione, the publication is European Journal of Organic Chemistry (2011), 777-785, S777/1-S777/16, database is CAplus.

The mechanism of the isotopic exchange reaction of the 5-H hydrogen of uracil and its Me derivatives in water and organic solvents has been studied. The key intermediate of the reaction is a C-5 tautomer of uracil in which the carbon atom at the 5-position has two hydrogen atoms, its hybridization is changed from sp² to sp³, and the aromaticity of the pyrimidine ring is lost. We have used ¹H NMR spectroscopy to follow the kinetics of the hydrogen/deuterium exchange reaction. In aqueous media a general base catalysis was observed and for exchange in organic solvents we have proposed a reaction mechanism that involves the participation of solvent mols. The reaction rates determined by NMR can be rationalized by d. functional computations. We have shown that the hydrogen-to-deuterium exchange reaction is much faster in some suitable nucleophilic solvents than in water. These findings could be used for the tritium labeling of pyrimidine nucleic acid bases.

European 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, Name: 3-Methylpyrimidine-2,4(1H,3H)-dione.

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

Dracinsky, Martin published the artcileIsotope exchange reactions of the hydrogen H-5 of selected pyrimidine derivatives and the preparation of tritium-labeled pyrimidines, Product Details of C5H6N2O2, the publication is Collection of Czechoslovak Chemical Communications (2011), 76(12), 1567-1577, database is CAplus.

The hydrogen-to-deuterium isotope exchange reaction of hydrogen in position 5 of pyrimidine derivatives was studied using NMR techniques. The dependence of the reaction rate on the pH and on the solvent composition was explored. In tracer experiments using tritiated water, the application of this exchange reaction was tested for the preparation of pyrimidine derivatives labeled by tritium.

Collection of Czechoslovak Chemical Communications 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

Paudler, William W. published the artcileBromination of some pyridine and diazine N-oxides, SDS of cas: 31401-45-3, the publication is Journal of Organic Chemistry (1983), 48(7), 1064-9, database is CAplus.

Selected monosubstituted pyridines, pyrazines, pyrimidines, and their N-oxides, having an electron-donating substituent, were successfully brominated under very mild conditions. The N-oxide function itself is not sufficient to cause these π-deficient systems to undergo electrophilic aromatic halogenation. Only strongly electron-donating substituents (amino groups) activate the heterocyclic nucleus toward bromination. These substituents direct the electrophilic substitution ortho/para to them with or without the N-oxide group present. Pyridine and diazines with moderately activating substituents such as alkoxy groups are brominated only when their ortho/para activation is augmented by the activation of the N-oxide function. Failure to brominate 5-methoxypyrimidine 1-oxide may well reflect the greater π deficiency of the pyrimidine ring.

Journal of Organic Chemistry published new progress about 31401-45-3. 31401-45-3 belongs to pyrimidines, auxiliary class Pyrimidine,Amine, name is N,N-Dimethylpyrimidin-4-amine, and the molecular formula is C6H9N3, SDS of cas: 31401-45-3.

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

Ren, Sijin published the artcileAn EOM-CCSD-PCM Benchmark for Electronic Excitation Energies of Solvated Molecules, Related Products of pyrimidines, the publication is Journal of Chemical Theory and Computation (2017), 13(1), 117-124, database is CAplus and MEDLINE.

In this work, we benchmark the equation of motion coupled cluster with single and double excitations (EOM-CCSD) method combined with the polarizable continuum model (PCM) for the calculation of electronic excitation energies of solvated mols. EOM-CCSD is one of the most accurate methods for computing one-electron excitation energies, and accounting for the solvent effect on this property is a key challenge. PCM is one of the most widely employed solvation models due to its adaptability to virtually any solute and its efficient implementation with d. functional theory methods (DFT). Our goal in this work is to evaluate the reliability of EOM-CCSD-PCM, especially compared to time-dependent DFT-PCM (TDDFT-PCM). Comparisons between calculated and exptl. excitation energies show that EOM-CCSD-PCM consistently overestimates exptl. results by 0.4-0.5 eV, which is larger than the expected EOM-CCSD error in vacuo. We attribute this decrease in accuracy to the approximated solvation model. Thus, we investigate a particularly important source of error: the lack of H-bonding interactions in PCM. We show that this issue can be addressed by computing an energy shift, Δ_HB, from bare-PCM to microsolvation + PCM at DFT level. Our results show that such a shift is independent of the functional used, contrary to the absolute value of the excitation energy. Hence, we suggest an efficient protocol where the EOM-CCSD-PCM transition energy is corrected by Δ_HB(DFT), which consistently improves the agreement with the exptl. measurements.

Journal of Chemical Theory and Computation 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

Xu, Li published the artcileSynthesis, Structure-Activity Relationships, and In Vivo Evaluation of Novel Tetrahydropyran-Based Thiodisaccharide Mimics as Galectin-3 Inhibitors, Formula: C7H6N2O, the publication is Journal of Medicinal Chemistry (2021), 64(10), 6634-6655, database is CAplus and MEDLINE.

Galectin-3 is a member of a family of β-galactoside-binding proteins. A substantial body of literature reports that galectin-3 plays important roles in cancer, inflammation, and fibrosis. Small-mol. galectin-3 inhibitors, which are generally lactose or galactose-based derivatives, have the potential to be valuable disease-modifying agents. In our efforts to identify novel galectin-3 disaccharide mimics to improve drug-like properties, we found that one of the monosaccharide subunits can be replaced with a suitably functionalized tetrahydropyran ring. Optimization of the structure-activity relationships around the tetrahydropyran-based scaffold led to the discovery of potent galectin-3 inhibitors. Three compounds (identified within) were selected for further in vivo evaluation. The synthesis, structure-activity relationships, and in vivo evaluation of novel tetrahydropyran-based galectin-3 inhibitors are described.

Journal of Medicinal Chemistry published new progress about 1059705-07-5. 1059705-07-5 belongs to pyrimidines, auxiliary class Pyrimidine, name is 5-Ethynyl-2-methoxypyrimidine, and the molecular formula is C4H4OS, Formula: C7H6N2O.

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

Gompper, Rudolf published the artcileAminopyridines, aminopyrimidines, and tris(dimethylamino) benzene from (aza) vinamidinium and (aza)pentamethinium salts, Application of N,N-Dimethylpyrimidin-4-amine, the publication is Angewandte Chemie (1981), 93(3), 298-9, database is CAplus.

Reaction of H₂XC(NMe₂):N⁺:CRNMe₂.ClO₄^– (X = CH, R = H, Ph, Me, NMe₂; X = N, R = H) with Me₂NCH(OEt)₂ gave 74-90% Me₂NCH:XC(NMe₂):N⁺:CRNMe₂.ClO₄^– (I). I (X = CH) were cyclized with NH₄OAc to give the pyrimidines II (R = H, Ph, NMe₂). The pyridine III was obtained by treating I (X = CH, R = Me) with base. 1,3,5-(Me₂N)₃C₆H₃ was obtained in 70% yield by treating Me₂NCMe:C:C(NMe₂)₂.HClO₄ with Me₂NCMe(OEt)₂.

Angewandte Chemie published new progress about 31401-45-3. 31401-45-3 belongs to pyrimidines, auxiliary class Pyrimidine,Amine, name is N,N-Dimethylpyrimidin-4-amine, and the molecular formula is C6H9N3, Application of N,N-Dimethylpyrimidin-4-amine.

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