Tag: M.W=150-200

Poole, Colin F. published the artcileSelection of calibration compounds for selectivity evaluation of wall-coated, open-tubular columns for gas chromatography by the solvation parameter model, Application of 2-Methoxynaphthalene, the publication is Journal of Chromatography A (2020), 461500, database is CAplus and MEDLINE.

To facilitate faster selectivity evaluation of wall-coated, open-tubular columns using the solvation parameter model a reduced set of calibration compounds is identified and validated for the temperature ranges 60-140°C and 160-260°C. The Kennard-Stone uniform mapping algorithm is used to identify the calibration compounds from a larger database of compounds with known retention properties previously adopted for column selectivity evaluation. Thirty-five compounds for each temperature range are required to minimize the standard deviation of the system constants used for selectivity evaluation and to minimize differences between system constants determined by conventional calibration and the reduced calibration compounds The models for the reduced calibration compounds on ten siloxane-based and poly(ethylene glycol) stationary phases have a coefficient of determination of 0.984 to 0.998 and standard error of the estimate of 0.012 to 0.30. The predictive capability of models is evaluated for the reduced sets of calibration compounds using external test sets with ranking of the calibration models by changes in the average error, average absolute error and root mean square error of prediction for the test sets. For the selected thirty-five reduced calibration compounds the range for the average absolute error was 0.014 to 0.033 and 0.016 to 0.040 for the root mean square error of prediction for the independent test sets.

Journal of Chromatography A published new progress about 93-04-9. 93-04-9 belongs to ethers-buliding-blocks, auxiliary class Naphthalene,Ether, name is 2-Methoxynaphthalene, and the molecular formula is C11H10O, Application of 2-Methoxynaphthalene.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Schuster, Ingeborg I. published the artcileA carbon-13 NMR study of the 1:1 hydrogen bond between trifluoroacetic acid and aromatic ethers in deuteriochloroform, HPLC of Formula: 2944-47-0, the publication is Journal of Organic Chemistry (1991), 56(2), 624-31, database is CAplus.

From the measured values of the equilibrium constants and ¹³C NMR shift changes for 1:1 hydrogen bonding of trifluoroacetic acid with 2-alkyl- and 2,6-dialkylanisoles and 7-alkyl-2,3-dihydrobenzofurans in deuteriochloroform, conclusions are drawn concerning the stereochemistries of the hydrogen bonded complexes. The data indicate that hydrogen bonding of the planar 2-alkylanisoles may involve rotation of the methoxy group about the aryl-OCH₃ bond, the rotational angles ranging from 13° (anisole) to 43° (tert-butylanisole). The values of log K₁ correlate roughly with the torsional potential for methoxy group rotation in anisole, recently obtained by means of quantum mechanics, and with the angle-dependent electron densities at the methoxy oxygens that have been calculated for these o-alkylanisoles. The equilibrium constants for hydrogen bonding of the 2,6-dialkylanisoles also follow the predicted order of increasing methoxy oxygen electronic charge. The results for the rotationally rigid 2,3-dihydrobenzofurans are compatible with preferential involvement of the oxygen sp² lone electron pair in hydrogen bond formation.

Journal of Organic Chemistry published new progress about 2944-47-0. 2944-47-0 belongs to ethers-buliding-blocks, auxiliary class Benzene,Ether, name is 2-Isopropylanisole, and the molecular formula is C15H14O, HPLC of Formula: 2944-47-0.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Yan, Boyu published the artcileCatalyst-free reductive hydrogenation or deuteration of aryl-heteroatom bonds induced by light, SDS of cas: 93-04-9, the publication is Organic Chemistry Frontiers (2021), 8(19), 5244-5249, database is CAplus.

A simple and catalyst-free photochem. strategy for the direct reduction of aryl trimethylammonium salts ArNMe₃OTf (Ar = biphenyl-4-yl, 2-naphthyl, quinolin-3-yl, etc.), aryl triflates Ar¹OTf (Ar¹ = biphenyl-3-yl, 1,6-dimethylpyridin-4-yl, benzothiazol-5-yl, etc.), and haloarenes Ar²X (Ar² = biphenyl-4-yl, 2-naphthyl, quinolin-4-yl, etc.; X = Cl, Br, I) to arenes ArH/Ar¹H or deuterium-labeled arenes ArD/Ar¹D/Ar²D was described. A broad range of substrate scope was demonstrated with high yields and deuterium incorporations. Radical clock experiments indicate the formation of aryl radical intermediates that can also be trapped by phenols.

Organic Chemistry Frontiers published new progress about 93-04-9. 93-04-9 belongs to ethers-buliding-blocks, auxiliary class Naphthalene,Ether, name is 2-Methoxynaphthalene, and the molecular formula is C19H14O2, SDS of cas: 93-04-9.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Feng, Chengqi published the artcileAcidolysis mechanism of lignin from bagasse during p-toluenesulfonic acid treatment, SDS of cas: 134-96-3, the publication is Industrial Crops and Products (2022), 114374, database is CAplus.

Lignin was efficiently separated from lignocellulosic biomass using p-toluenesulfonic acid (p-TsOH) treatment. However, lignin depolymerization and acidolysis have not been studied to date. In this study, the mechanism of lignin acidolysis was investigated. The structure of lignin in bagasse before and after the p-TsOH treatment was analyzed. The efficiency and selectivity of lignin depolymerization were evaluated. The lignin removal rate reached 88.81%. Hemicellulose was completely removed from lignin, and cellulose destruction was inhibited. The structure of lignin in bagasse was analyzed using NMR. The results revealed that α-methoxylated β-O-4 intermediates were formed during lignin depolymerization This indicated that the benzyl ether bonds were effectively catalyzed and broke, thereby promoting lignin dissolution The lignin-carbohydrate complex structure was destroyed. The insoluble and soluble lignin in the hydrolyzate were analyzed using NMR and gas chromatog.-mass spectrometry. The results indicated that the catalyst promoted breaking of the C_β-O bonds in the β-O-4 structures. Phenols and Hibbert ketones were formed. In addition, lignin sulfonation was confirmed by the presence of di-o-tolusulfone and di-p-tolusulfone. The low contents of β-β and β-5 bonds in the reaction products indicated that lignin condensation was inhibited. The results demonstrated that lignin acidolysis was synergistically catalyzed by H⁺ and p-TsOH. It provides important theor. support for efficient and clean separation of lignin using the p-TsOH treatment.

Industrial Crops and Products published new progress about 134-96-3. 134-96-3 belongs to ethers-buliding-blocks, auxiliary class Immunology/Inflammation,COX,Natural product, name is 4-Hydroxy-3,5-dimethoxybenzaldehyde, and the molecular formula is C9H10O4, SDS of cas: 134-96-3.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Dai, Guohua published the artcilePlant-derived lipids play a crucial role in forest soil carbon accumulation, Formula: C9H10O4, the publication is Soil Biology & Biochemistry (2022), 108645, database is CAplus.

Plant and microbial residues are two main sources of soil organic carbon (SOC). While recent studies have extensively examined the distribution of microbial necromass in different ecosystems, how plant residues (in particular, non-lignin components) contribute to SOC accumulation is less clear, especially in forests which make up 50% of the global soil carbon storage. Filling this knowledge gap will help us better understand SOC accumulation patterns and their response to land-use changes. Here, we analyze plant- and microbial-derived biomarkers (including lignin phenols, amino sugars, free and hydrolysable lipids) in the topsoil of major forest types in China and compare their distribution patterns together with the existing data (for lignin phenols and amino sugars) in forests and grasslands distributed globally. At the global scale, forests contain significantly less microbial necromass in SOC compared with grasslands, suggesting higher contribution of plant-derived components to forest SOC. However, plant-derived lignin phenols do not seem to play a major role in SOC accumulation, given their neg. relationship with SOC contents. Instead, leaf- and root-derived hydrolysable lipids constitute a much higher proportion of SOC than lignin phenols in the investigated forests of China, even compared to grassland soils. Moreover, in contrast to lignin phenols, both SOC contents and the relative abundance of hydrolysable plant lipids in SOC increase with decreasing soil pH, increasing reactive iron and aluminum contents and with increasing lignin oxidation (indicated by acid-to-aldehyde ratios) in these forest soils. These results suggest that with increasing lignin decomposition, plant lipids and SOC accumulated via (oxyhydr)oxide protection. Collectively, our results demonstrate differential importance of plant-derived components in SOC accumulation in forests vs. grasslands and highlight that plant lipids play a more important part than lignin in forest SOC accumulation. Quant. investigations on the distribution of plant-derived lipids in addition to lignin in forest soils may help to elucidate pathways and hotspots of plant component-dominated SOC accrual.

Soil Biology & Biochemistry published new progress about 134-96-3. 134-96-3 belongs to ethers-buliding-blocks, auxiliary class Immunology/Inflammation,COX,Natural product, name is 4-Hydroxy-3,5-dimethoxybenzaldehyde, and the molecular formula is C9H10O4, Formula: C9H10O4.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Homann, Julia published the artcileDevelopment of a Method for Anodic Degradation of Lignin for the Analysis of Paleo-Vegetation Proxies in Speleothems, Computed Properties of 134-96-3, the publication is ChemElectroChem (2022), 9(6), e202101312, database is CAplus.

Here we present an electrochem. method for the anodic oxidation and subsequent degradation of lignin in speleothems to utilize the resulting lignin oxidation products (LOPs) as paleo-vegetation markers. LOPs were analyzed using an ultra-high performance liquid chromatog. (UHPLC) system coupled to a high-resolution mass spectrometer (HRMS). The method presented here achieved comparable or even higher LOP concentrations than established CuO and CuSO₄ oxidation methods. The method represents a new tool for the anal. and reconstruction of paleo-vegetation and has the potential to be applied to other climate archives.

ChemElectroChem published new progress about 134-96-3. 134-96-3 belongs to ethers-buliding-blocks, auxiliary class Immunology/Inflammation,COX,Natural product, name is 4-Hydroxy-3,5-dimethoxybenzaldehyde, and the molecular formula is C9H10O4, Computed Properties of 134-96-3.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Baerncopf, Jamie published the artcilePrevalence of ignitable liquids in clothing with printing, Quality Control of 93-04-9, the publication is Forensic Science International (2020), 110312, database is CAplus and MEDLINE.

In this study, 141 shirts were evaluated to determine the prevalence of ignitable liquids in printed shirts. Both new and worn shirts were included in this study. Volatile components extracted from the shirts were noted and many of the most commonly encountered components could be contributed to human skin or laundry, personal hygiene, or personal care products. Volatile components that are known to be present in ignitable liquids were also identified, including toluene, C2-alkylbenzenes, and normal alkanes. An aromatic pattern consisting of toluene, C2-alkylbenzenes, and sometimes extending to the C3-alkylbenzenes or beyond was observed in 41% of the shirts in this study. This pattern was mainly visible in the aromatic extracted ion profile, though it was clearly identifiable in some total ion chromatograms. This high occurrence suggests that a caveat should be used if identifying an aromatic product in a clothing item with printing. Though several shirts showed multiple sequential n-alkanes, only one had a petroleum pattern that would be considered for identification.

Forensic Science International published new progress about 93-04-9. 93-04-9 belongs to ethers-buliding-blocks, auxiliary class Naphthalene,Ether, name is 2-Methoxynaphthalene, and the molecular formula is C11H10O, Quality Control of 93-04-9.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Baliah, V. published the artcileEvidence for steric enhancement of resonance in 2-alkylanisoles from ¹³C NMR T₁ relaxation times of methoxy-carbons and from atomic charges on methoxy-oxygens, Recommanded Product: 2-Isopropylanisole, the publication is Journal of the Indian Chemical Society (1993), 70(10), 841-2, database is CAplus.

The title study of MeOC₆H₄R-2 (R = H, alkyl) and MeOC₆H₃R¹R²-2,6 (R¹ = R² = alkyl) confirmed the steric enhancement of resonance in these compounds

Journal of the Indian Chemical Society published new progress about 2944-47-0. 2944-47-0 belongs to ethers-buliding-blocks, auxiliary class Benzene,Ether, name is 2-Isopropylanisole, and the molecular formula is C10H14O, Recommanded Product: 2-Isopropylanisole.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Wang, Jiangli published the artcileIn-Depth Identification of Phenolics Fractionated from Eucalyptus Kraft Lignin, Quality Control of 134-96-3, the publication is Advanced Sustainable Systems (2022), 6(5), 2100406, database is CAplus.

Kraft lignin, the principal byproduct of the pulping industry, is an abundant yet highly underutilized aromatic resource. It is useful due to the vast scales involved as a source of fuels, chems., and functional materials when suitable postprocessing is applied. It is deemed to be a renewable alternative to fossil sources. Because of the extreme complexity of kraft lignin, in-depth composition anal. and chem. structural identification are crucial for the development of effective valorization strategies. This work embarks on the characterization and identification of lignin-derived phenolic compounds in representative hardwood (Eucalyptus) kraft lignin after selective fractionation using a single solvent. Advanced 2D heteronuclear single quantum coherence (HSQC) NMR, ³¹P NMR, and mass spectrometry in combination with synthetic authentic compounds are used for the structural identification of the low-mol.-weight fraction of kraft lignin. A total of 20 phenolic compounds, including several novel monomers (catechols), dimers (diarylethanes, diarylethenes, etc.), and trimers with tri-Ph structures are systematically identified in the Eucalyptus kraft lignin. In addition, polysulfide is detected in the low-mol.-weight fraction, indicating that the oxidative polymerization of S^2-/HS^– occurrs during the kraft pulping process. An improved understanding of kraft lignin, especially the low-Mw fraction, is expected to provide essential information for the selective fractionation and valorization of lignin.

Advanced Sustainable Systems published new progress about 134-96-3. 134-96-3 belongs to ethers-buliding-blocks, auxiliary class Immunology/Inflammation,COX,Natural product, name is 4-Hydroxy-3,5-dimethoxybenzaldehyde, and the molecular formula is C9H22OSi, Quality Control of 134-96-3.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Hu, Boqin published the artcileEthanol extracts of Rhaponticum uniflorum (L.) DC flowers attenuate doxorubicin-induced cardiotoxicity via alleviating apoptosis and regulating mitochondrial dynamics in H9c2 cells, COA of Formula: C9H10O4, the publication is Journal of Ethnopharmacology (2022), 114936, database is CAplus and MEDLINE.

Loulu flowers (LLF) is the inflorescence of Rhaponticum uniflorum (L.) DC. (R. uniflorum), a member of the Compositae family. This plant possesses heat-clearing properties, detoxification effects, and is therefore frequently used for the treatment of cardiovascular diseases. Aim of this study: This study aimed to investigate the cardioprotective effects of ethanol extracts of LLF against doxorubicin (DOX)-induced cardiotoxicity and explore the associated mechanisms. Ethanol extracts of LLF were prepared and analyzed by LC-ESI-MS/MS. DOX-treated H9c2 cells and DOX-treated zebrafish models were used to explore the cardioprotective effect of ethanol extracts on myocardial function. The effects of LLF on DOX-induced cytotoxicity in H9c2 cells were investigated by MTT assay. Reactive Oxygen Species (ROS) levels, mitochondrial membrane potential (MMP), and nuclear translocation of NF-κB p65 were examined using fluorescent probes. The expression level of Bax, Bcl-2, PARP, caspase-3, cleaved-caspase3, caspase9, IκBα, p-IκBα, IKK, p-IKK, p65, p-p65, OPA1, Mfn1, MFF and Fis 1 and GAPDH was determined by western blotting. Twenty-five compounds were detected in ethanol extracts of LLF, include Nicotinamide, Coumarin, Parthenolide, and Ligustilide. Pre-treatment with LLF attenuated the DOX-induced decrease in viability and ROS production in H9c2 cells. Moreover, LLF treatment maintained the mitochondrial membrane integrity and suppressed apoptosis by upregulating expression level of Bcl-2 and downregulating the expression level of Bax, cleaved-caspase-3, cleaved-caspase-9 and cleaved-PARP. In addition, LLF significantly inhibited the DOX-induced activation of NF-κB signaling. Cells treated with DOX showed aberrant expression of mitochondrial dynamics related proteins, and these effects were alleviated by LLF pre-treatment. In conclusion, these results show that LLF can alleviate DOX-induced cardiotoxicity by blocking NF-κB signaling and re-balancing mitochondrial dynamics. Ethanol extracts of LLF is a potential treatment option to against DOX-induced cardiotoxicity.

Journal of Ethnopharmacology published new progress about 134-96-3. 134-96-3 belongs to ethers-buliding-blocks, auxiliary class Immunology/Inflammation,COX,Natural product, name is 4-Hydroxy-3,5-dimethoxybenzaldehyde, and the molecular formula is C9H10O4, COA of Formula: C9H10O4.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem