Day: November 10, 2022

Rezaei, Saghar published the artcileMono- and multifold C-C coupling reactions catalyzed by a palladium complex encapsulated in MIL-Cr as a three dimensional nano reactor, Computed Properties of 36847-11-7, the main research area is phenylboronic acid halobenzene chromium MOF encapsulated palladium Suzuki reaction; biaryl preparation green chem; styrene halobenzene chromium MOF encapsulated palladium Heck reaction; styrylbenzene preparation green chem; reusable chromium MOF encapsulated palladium complex catalyst preparation.

The organic palladium complex (trans-dichlorobis(4-iodoaniline-κN)palladium(II)) was encapsulated into a porous metal-organic framework MIL-Cr (Pd complex@MIL-Cr) using ship-in-a-bottle strategy. The novel catalyst as a three dimensional nanoreactor was fully characterized using different techniques such as XRD, BET, XPS, SEM, EDX, TEM and ICP. The Pd complex@MIL-Cr was isostructural to the parent MIL-Cr framework, with a high surface area and pore volume of ca. 1418 m2 g-1 and 0.87 cm3 g-1, resp. The nanoreactor was highly efficient in the catalytic conversion of aryl halides, showing extraordinarily higher activity than the homogeneous Pd counterparts. Surprisingly, high yields were achieved in Suzuki-Miyaura and Heck coupling reactions of chloroarenes bearing a wide range of substituents. Besides, this protocol could be extended to the cross-couplings of 2-bromo and 2,6-dibromopyridine with arylboronic acids in excellent yields at room temperature The Pd complex@MIL-Cr was also used as an efficient and convenient catalyst for the preparation of a series of C3-sym. mols. with benzene, pyridine or pyrimidine units as the central core. Moreover, the catalyst could be recovered easily and reused several times without any considerable loss of its catalytic activity. Investigation of the nature of the recovered catalyst showed that the catalyst was converted to Pd nanoparticles.

RSC Advances published new progress about Aryl alkenes Role: SPN (Synthetic Preparation), PREP (Preparation). 36847-11-7 belongs to class pyrimidines, name is 2,4,6-Tribromopyrimidine, and the molecular formula is C4HBr3N2, Computed Properties of 36847-11-7.

Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia

Si, Xingyu published the artcileDetecting Low-Abundance Molecules at Single-Cell Level by Repeated Ion Accumulation in Ion Trap Mass Spectrometer, Name: 5-Methylcytosinehydrochloride, the main research area is low abundance mol detection cell ion trap mass spectrometry.

Low-abundance metabolites or proteins in single-cell samples are usually undetectable by mass spectrometry (MS) due to the limited amount of substances in single cells. This limitation inspired the authors to further enhance the sensitivity of com. mass spectrometers. Herein, the authors developed a technique named repeated ion accumulation by ion trap MS, which is capable of enhancing the sensitivity by selectively and repeatedly accumulating ions in a linear ion trap for up to 25 cycles. The increase in MS sensitivity was pos. correlated with the number of repeated cycles. When ions were repeatedly accumulated for 25 cycles, the sensitivity of ATP detection was increased by 22-fold within 1.8 s. The authors’ technique could stably detect low-abundance ions, especially MSn ions, at the single-cell level, such as 5-methylcytosine hydrolyzed from sample equivalent to ∼0.2 MCF7 cell. The strategy presented in this study offers the possibility to aid single-cell anal. by enhancing MS detection sensitivity.

Analytical Chemistry (Washington, DC, United States) published new progress about Electrospray ionization mass spectrometry (nanospray ionization, ion trap). 58366-64-6 belongs to class pyrimidines, name is 5-Methylcytosinehydrochloride, and the molecular formula is C5H8ClN3O, Name: 5-Methylcytosinehydrochloride.

Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia

Heinisch, Gottfried published the artcileNovel diazinyl 3-pyridyl ketones: efficient synthesis and complete assignment of 1H and 13C NMR spectra, SDS of cas: 42839-08-7, the main research area is diazinyl pyridyl ketone preparation NMR.

The preparation of six diazinyl 3-pyridyl ketones is described: 3-pyridyl 3-pyridazinyl ketone, 3-pyridyl 4-pyridazinyl ketone, 3-pyridyl 2-pyrimidinyl ketone, 3-pyridyl 4-pyrimidinyl ketone, 3-pyridyl 5-pyrimidinyl ketone, and 3-pyridyl 2-pyrazinyl ketone. Detailed 1H NMR data of these novel building blocks are given.

Journal of Heterocyclic Chemistry published new progress about Ketones Role: PRP (Properties), SPN (Synthetic Preparation), PREP (Preparation). 42839-08-7 belongs to class pyrimidines, name is Ethyl pyrimidine-2-carboxylate, and the molecular formula is C7H8N2O2, SDS of cas: 42839-08-7.

Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia

Rao, C. Janakiram published the artcileSubstituent Effects on Photochemical Hydrogen Abstraction in 2-Acylpyridines, 2-Acylpyrazines, and 4-Acylpyrimidines, Quality Control of 67073-96-5, the main research area is photochem hydrogen abstraction acylheterocycle substituent effect; ketone photochem hydrogen abstraction.

Stern-Volmer quenching of the photochem. of I indicates that N- and O-abstraction are quenched at different rates . When I is sensitized with triplet sensitizers of increasing ET, N-abstraction increases . These data indicate that N- and O-abstraction in I take place from distinguishable triplet states. Survey of Φp’s of ring-substituted nitrogen-containing heteroaryl ketones (e.g. II; R= H,Me,CN) demonstrates the effect of substitution on the competition between N- and O-abstraction . For methyl- and dicyano-substituted ketones, the results can be understood simply in terms of shifts in ET of the nπ* and ππ* states of the heterocycle. The photochem. of all these ketones requires consideration of interactions among three triplet states.

Journal of Organic Chemistry published new progress about Heterocyclic compounds, nitrogen Role: RCT (Reactant), RACT (Reactant or Reagent). 67073-96-5 belongs to class pyrimidines, name is 1-(6-Methylpyrimidin-4-yl)ethanone, and the molecular formula is C7H8N2O, Quality Control of 67073-96-5.

Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia

Li, Chun published the artcileIonic liquid promoted synthesis of heterocycle-fused pyrimidine-2,4(1H,3H)-diones utilising CO2, Computed Properties of 36075-35-1, the main research area is heterocycle pyrimidine dione preparation green chem; carbon dioxide cyclization ionic liquid catalyst.

An efficient ionic liquid system was developed for the preparation of various heterocycle-fused pyrimidine-2,4(1H,3H)-diones in moderate to excellent yields (52-95%). It was found that 1,5-diazabicyclo[4.3.0]non-5-ene trifluoroethanol [HDBN+][TFE-], a simple and easily prepared ionic liquid, could act as both the solvent and reaction promoter, and that the reactions could be efficiently carried out at atm. pressures of CO2.

Tetrahedron Letters published new progress about Fused heterocyclic compounds Role: SPN (Synthetic Preparation), PREP (Preparation). 36075-35-1 belongs to class pyrimidines, name is 7-Methylpyrido[2,3-d]pyrimidine-2,4-diol, and the molecular formula is C8H7N3O2, Computed Properties of 36075-35-1.

Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia

Chen, Ying-Chu published the artcileC-N Coupling of DNA-Conjugated (Hetero)aryl Bromides and Chlorides for DNA-Encoded Chemical Library Synthesis, Application In Synthesis of 60703-80-2, the main research area is DNA encoded heteroaryl amide library synthesis.

DNA-encoded chem. library (DECL) screens are a rapid and economical tool to identify chem. starting points for drug discovery. As a robust transformation for drug discovery, palladium-catalyzed C-N coupling is a valuable synthetic method for the construction of DECL chem. matter; however, currently disclosed methods have only been demonstrated on DNA-attached (hetero)aromatic iodide and bromide electrophiles. We developed conditions utilizing an N-heterocyclic carbene-palladium catalyst that extends this reaction to the coupling of DNA-conjugated (hetero)aromatic chlorides with (hetero)aromatic and select aliphatic amine nucleophiles. In addition, we evaluated steric and electronic effects within this catalyst series, carried out a large substrate scope study on two representative (hetero)aryl bromides, and applied this newly developed method within the construction of a 63 million-membered DECL.

Bioconjugate Chemistry published new progress about Anilines Role: CMB (Combinatorial Study), RCT (Reactant), RACT (Reactant or Reagent). 60703-80-2 belongs to class pyrimidines, name is 6-Bromothieno[2,3-d]pyrimidine, and the molecular formula is C6H3BrN2S, Application In Synthesis of 60703-80-2.

Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia

Wagner, Gabor published the artcileCovalent inhibition of the histamine Hi3 receptor, Category: pyrimidines, the main research area is histamine covalent inhibition receptor; G protein-coupled receptor (GPCR); Histamine H3 receptor; covalent binder; isothiocyanate.

Covalent binding of G protein-coupled receptors by small mols. is a useful approach for better understanding of the structure and function of these proteins. We designed, synthesized and characterized a series of 6 potential covalent ligands for the histamine Hi3 receptor (Hi3R). Starting from a 2-amino-pyrimidine scaffold, optimization of anchor moiety and warhead followed by fine-tuning of the required reactivity via scaffold hopping resulted in the isothiocyanate Hi3R ligand 44. It shows high reactivity toward glutathione combined with appropriate stability in water and reacts selectively with the cysteine sidechain in a model nonapeptide equipped with nucleophilic residues. The covalent interaction of 44 with Hi3R was validated with washout experiments and leads to inverse agonism on Hi3R. Irreversible binder 44 (VUF15662) may serve as a useful tool compound to stabilize the inactive Hi3R conformation and to study the consequences of prolonged inhibition of the Hi3R.

Molecules published new progress about Histamine H3 receptor agonists Role: BSU (Biological Study, Unclassified), BIOL (Biological Study). 73576-33-7 belongs to class pyrimidines, name is 4-Chloro-6-isopropylpyrimidin-2-amine, and the molecular formula is C7H10ClN3, Category: pyrimidines.

Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia

Votruba, Ivan published the artcileSynthesis of 2′-deoxy-β-D-ribonucleosides and 2,3-dideoxy-β-D-pentofuranosides on immobilized bacterial cells, Computed Properties of 19030-75-2, the main research area is deoxynucleoside transglycosylation immobilized Escherichia; nucleoside deoxy dideoxy biosynthesis Escherichia.

Alginate gel-entrapped cells of auxotrophic thymine-dependent strain of E. coli catalyze the transfer of 2-deoxy-D-ribofuranosyl moiety of 2′-deoxyuridine to purine and pyrimidine bases as well as their aza and deaza analogs. All experiments invariably gave β-anomers; in most cases, the reaction was regiospecific, affording N9-isomers in the purine and N1-isomers in the pyrimidine series. Also a 2,3-dideoxynucleoside can serve as donor of the glycosyl moiety. The acceptor activity of purine bases depends only little on substitution, the only condition being the presence of N7-nitrogen atom. On the other hand, in the pyrimidine series the activity is limited to only a narrow choice of mostly short 5-alkyl and 5-halo uracil derivatives Heterocyclic bases containing amino groups are deaminated; this can be avoided by conversion of the base to the corresponding N-dimethylaminomethylene derivative which is then ammonolyzed. The method was verified by isolation of 9-(2-deoxy-β-D-ribofuranosyl) derivatives of adenine, guanine, 2-chloroadenine, 6-methylpurine, 8-azaadenine, 8-azaguanine, 1-deazaadenine, 3-deazaadenine, 1-(2-deoxy-β-D-ribofuranosyl) derivatives of 5-ethyluracil, 5-fluorouracil, and 9-(2,3-dideoxy-β-D-pentofuranosyl)hypoxanthine, 9-(2,3-dideoxy-β-D-pentofuranosyl)-6-methylpurine, and other nucleosides.

Collection of Czechoslovak Chemical Communications published new progress about Escherichia coli. 19030-75-2 belongs to class pyrimidines, name is 5-N-Propyluracil, and the molecular formula is C7H10N2O2, Computed Properties of 19030-75-2.

Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia

Yamagami, Chisako published the artcileHydrophobicity parameter of diazines IV: a new hydrogen-accepting parameter of monosubstituted (di)azines for the relationship of partition coefficients in different solvent systems, Application of Ethyl pyrimidine-2-carboxylate, the main research area is hydrophobicity diazine hydrogen accepting parameter scale; monosubstituted azine partition solvent effect LFER hydrophobicity.

The authors recently proposed a new H-accepting scale, SHA, for each member of the substituted (di)azine series from the heat of formation calculated under various dielec. environments by the COSMO method. The SHA scale was used to examine relations between log PCL (PCL: CHCl3/H2O partition coefficient) and log Poct (Poct: 1-octanol/H2O partition coefficient) for each of the 2-substituted pyridine (I), monosubstituted pyrazine (II), and pyrimidine (III) series. This SHA parameter worked nicely, representing the H-accepting effect of the solute mol. A correlation equation with excellent quality, such as log PCL = a log Poct + sSHA + constant, was obtained for each series. The authors further defined the parameter SHA/PY, derived from SHA values for the heterocyclic series by shifting the reference points to unsubstituted pyridine, to unify sep. derived correlation equations. Thus, the correlation between log PCL and log Poct for all combined data of three series was derived by using a single equation as log PCL = a log Poct + sSHA/PY + constant The SHA parameters were reasonably considered as being free-energy related, and the rationale for the H-bond-acceptor scale was presented.

Journal of Pharmaceutical Sciences published new progress about Correlation analysis. 42839-08-7 belongs to class pyrimidines, name is Ethyl pyrimidine-2-carboxylate, and the molecular formula is C7H8N2O2, Application of Ethyl pyrimidine-2-carboxylate.

Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia

Sakai, Holt A. published the artcileCross-Electrophile Coupling of Unactivated Alkyl Chlorides, Recommanded Product: 5-Chloro-2-(methylthio)pyrimidine, the main research area is unactivated alkyl aryl chloride cross electrophile coupling iridium photocatalyst.

Overcoming intrinsic limitations of C(sp3)-Cl bond activation, the development of a novel organosilane reagent Si(TMS)3(N)R1R2 (R1 = adamantyl, tert-Bu, i-Pr, n-Bu; R2 = H) that can participate in chlorine atom abstraction under mild photocatalytic conditions were reported. In particular, the application of this mechanism to a dual nickel/photoredox catalytic protocol that enables the first cross-electrophile coupling of unactivated alkyl chlorides R3Cl (R3 = cyclohexyl, oxan-4-yl, 4-cyanobutyl, etc.) and aryl chlorides R4Cl (R4 = pyridin-4-yl, quinolin-3-yl, 2-(methylsulfanyl)pyrimidin-5-yl, etc.) was described. Employing these low-toxicity, abundant, and com. available organochloride building blocks, this methodol. allows access to a broad array of highly functionalized C(sp2)-C(sp3) coupled adducts, e.g., I including numerous drug analogs.

Journal of the American Chemical Society published new progress about Bond activation (C-Cl). 38275-42-2 belongs to class pyrimidines, name is 5-Chloro-2-(methylthio)pyrimidine, and the molecular formula is C5H5ClN2S, Recommanded Product: 5-Chloro-2-(methylthio)pyrimidine.

Referemce:
Pyrimidine | C4H4N2 – PubChem,
Pyrimidine – Wikipedia