Tag: M.W=100-150

Barbieri, Giorgio published the artcileInternal rotation of the NN-dimethylamino-group in aromatic and heteroaromatic systems, Category: pyrimidines, the publication is Journal of the Chemical Society, Perkin Transactions 2: Physical Organic Chemistry (1972-1999) (1979), 330-6, database is CAplus.

The title rotation was examined by comparing thermodn. activation parameters obtained exptl. with energy differences between ground and transition state evaluated by semiempirical MO calculations and describing the mol. electronic characteristics which determine the barriers to rotation. The rotational behavior in the N-protonated and N-alkylated forms relative to the free base of some (dimethylamino)pyridines was also examined Semiempirical calculations were used to predict the activation parameters and to describe the rotational path in these systems.

Journal of the Chemical Society, Perkin Transactions 2: Physical Organic Chemistry (1972-1999) 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, Category: pyrimidines.

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

Barnes, J. published the artcileThe protonation state of one-electron reduced cytosine and adenine. 1. Initial protonation sites at low temperatures in glassy solids, Safety of N,N-Dimethylpyrimidin-4-amine, the publication is Journal of Physical Chemistry (1993), 97(13), 3401-8, database is CAplus.

ESR spectra of cytosine and adenine, one-electron reduced in a 9 M LiCl glass at 4° K, show that in each case protonation occurs at the amino group. In order to understand this, a number of one-electron-reduced cytosine and adenine analogs in different glassy environments were produced, at 4° K, and used Q-band EPR to determine the sites of protonation. That the specific association of Li⁺ with the ring nitrogen blocks protonation at the expected sites, N3 of cytosine and N1 of adenine, diverting protonation to the less basic amino group was concluded.

Journal of Physical 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, Safety of N,N-Dimethylpyrimidin-4-amine.

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

Silva, F. published the artcileSite- and bond-selective H- formation in methylated pyrimidine bases driven by potassium-molecule collisions, Category: pyrimidines, the publication is Journal of Physics: Conference Series (2012), 388(Part 1), 012040/1-012040/6, database is CAplus.

Electron transfer in alkali-mol. collisions to gas phase thymine and uracil yielding H- formation is selectively controlled in the energy range between 5 and 65 eV. By tuning the collision energy, electron transfer from the alkali to methylated thymine (at the N1 position), methylated uracil (at the N3 position) and partly deuterated thymine, enables H-formation. Such process proceeds not only through the breaking of the (C-H) against (N-H) bonds but also through N1 against N3 sites. Such selectivity, as far as bond and site are concerned, is here reported for the first time in collision induced dissociation experiments by alkali-mol. interactions.

Journal of Physics: Conference Series 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 C17H14O5, Category: pyrimidines.

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

Silva, F. published the artcileSite and bond selective H- formation in methylated pyrimidine bases driven by potassium molecule collisions, Category: pyrimidines, the publication is Journal of Physics: Conference Series (2012), 388(Part 10), 102032/1, database is CAplus.

In this study we present for the first time site (N₁-H/N₃-H) and bond (N-H/C-H) selectivity of H- formation in 1-methylthymine, 3-methyluracil and deuterated thymine (C positions) triggered by potassium mol. collisions. By comparing the H loss of these mols. with H loss in thymine and uracil and setting the energy one can predict site and bond selectivity in these set of mols.

Journal of Physics: Conference Series 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 C23H43NP2, Category: pyrimidines.

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

Ribeiro da Silva, Manuel A. V. published the artcileExperimental study on the thermochemistry of some amino derivatives of uracil, COA of Formula: C5H6N2O2, the publication is Journal of Chemical Thermodynamics (2011), 43(11), 1763-1767, database is CAplus.

Values of the standard (p = 0.1 MPa) molar enthalpy of combustion, ΔcHm , of four crystalline compounds: 5-aminouracil, 6-aminouracil, 6-amino-1-methyluracil, and 6-amino-1,3-dimethyluracil, were determined, at T = 298.15 K, using a static bomb combustion calorimeter. The values obtained of standard molar enthalpy of combustion were used to derive the standard molar enthalpy of formation of the compounds investigated in their condensed phase and together with literature values of the standard molar enthalpy of sublimation, yielded the standard molar enthalpies of formation in the gaseous phase. These are discussed in terms of the effects of the mol. structure on the relative enthalpic stability.

Journal of Chemical Thermodynamics 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, COA of Formula: C5H6N2O2.

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

Krchnak, V. published the artcilePreparation and some reactions of 2,5-substituted pyrimidines, Synthetic Route of 56621-93-3, the publication is Collection of Czechoslovak Chemical Communications (1975), 40(5), 1384-9, database is CAplus.

The title compounds I (X = H, NH2, SH, SMe) were prepared by direct synthesis from [Me2NCH:C(CH:NMe2)N:CHNMe2]+ClO4- and HN:CXNH2. The reactants were reluxed in EtOH with dropwise addition of MeONa and HNEt2 distilled off in vacuo. I (X = H) was accompanied by [Me2NCH:NCH:NMe2]+ClO4- as by-product formed by reaction of liberated HNMe2 with HN:CHNH2. I (X = SMe) gave with NaClO, according to the reaction temperature, I (X = SOMe) or I (X = SO2Me) (II). II was especially ready for nucleophilic substitution of the SO2Me group and gave with alc. MeONa and with KCN in hot DMF, resp., I (X = OMe) and I (X = CN). Reaction of I (X = SH) with Me2SO in the presence of H2SO4 yielded III instead of the expected 2-hydroxypyrimidine derivative The readiness of II to undergo nucleophilic substitution by OMe and CN in the position 2 was compared with 3 addnl. 2-methylsulfonylpyrimidine 5-substituted with NHCHO, NH2, and H. The reaction rate was lowered by electron donating 5-substituents but the order of reactivities was different for OMe and CN.

Collection of Czechoslovak Chemical Communications published new progress about 56621-93-3. 56621-93-3 belongs to pyrimidines, auxiliary class Pyrimidine,Nitrile,Amine, name is 5-Aminopyrimidine-2-carbonitrile, and the molecular formula is C5H4N4, Synthetic Route of 56621-93-3.

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

Krchnak, V. published the artcileNovel pyrimidine derivatives, reactions, and ultraviolet spectra, Name: 5-Aminopyrimidine-2-carbonitrile, the publication is Collection of Czechoslovak Chemical Communications (1975), 40(5), 1396-402, database is CAplus.

The conditions were studied for selective hydrolysis of I (R1 = NH2, NMe2, OH, OAc, OMe, SH, SMe, H, F, Cl, Br, SOME2, SO2Me, CN) and the products characterized by uv spectra. Hydrolysis of I in boiling 0.02M H2SO4 or 0.2M AcOH gave the corresponding II, while treating I with 0.2M H2SO4 at 110° or with boiling 5% K2CO3 solution yielded the appropriate III. In strongly alk. media I (R1 = CN) gave III (R1 = CONH2) and III (R1 = CO2H). Special conditions were required for the hydrolysis of I (R1 = F) (IV) which gave in 3M KHF2 at 75° II (R1 = F) and at 120° afforded III (R1 = F), while heating IV in 5% K2CO3 solution yielded III (R1 = NMe2).

Collection of Czechoslovak Chemical Communications published new progress about 56621-93-3. 56621-93-3 belongs to pyrimidines, auxiliary class Pyrimidine,Nitrile,Amine, name is 5-Aminopyrimidine-2-carbonitrile, and the molecular formula is C5H4N4, Name: 5-Aminopyrimidine-2-carbonitrile.

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

Della Sala, Giorgio published the artcileSynthesis of uracil derivatives by oxidation of Fischer tungsten-carbene uracil complexes, Recommanded Product: 3-Methylpyrimidine-2,4(1H,3H)-dione, the publication is Journal of Organometallic Chemistry (2007), 692(8), 1623-1627, database is CAplus.

A study on the oxidation of Fischer tungsten-carbene uracil complexes has been carried out. E.g., oxidation of Fischer tungsten-carbene uracil complex I by Me₃NO gave 78% uracil II. Several commonly used oxidants gave results strongly influenced by the presence of substituents on the nitrogen atoms. In particular, the usual oxidants failed in the oxidation of 3-alkyl uracil carbene complexes. Finally, the authors showed that t-Bu hydroperoxide is able to oxidize successfully 3-alkyl uracil carbene complexes and can be used as a good alternative to the other methods.

Journal of Organometallic 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, Recommanded Product: 3-Methylpyrimidine-2,4(1H,3H)-dione.

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