Tag: 300-400

Miniaturized active air sampling method for the analysis of tire rubber pollutants from indoor and outdoor places was written by Armada, Daniel;Celeiro, Maria;Martinez-Fernandez, Antia;Nurerk, Piyaluk;Dagnac, Thierry;Llompart, Maria. And the article was included in Journal of Separation Science in 2021.Synthetic Route of C20H26O4 This article mentions the following:

An effective, quick, and sustainable air anal. method was developed to analyze 41 volatiles and semivolatile organic compounds present in tire rubber and crumb rubber materials. The proposed method, based on active sampling using a sorbent material followed by an ultrasound assisted extraction, was developed with the aim of obtaining a fast and simple procedure to determine polycyclic aromatic hydrocarbons, plasticizers, antioxidants, and vulcanization agents in air. A small amount of sorbent (25 mg) was used, and the analytes were recovered in only 1 mL of solvent. An exptl. design was applied to study the influence of main factors such as type of sorbent and type of solvent, extraction technique (ultrasound-assisted extraction and vortex extraction), extraction time, as well as the factor interactions. Under optimal conditions, no breakthrough occurs in the studied interval (up to 4 m³). Linearity was demonstrated in a wide concentration range. Accuracy of the total sampling-extraction anal. was evaluated obtaining satisfactory recoveries as well as good precision. The method was successfully applied to different outdoor and indoor air environments, including a recycled rubber synthetic turf football pitch. In the experiment, the researchers used many compounds, for example, Dicyclohexyl phthalate (cas: 84-61-7Synthetic Route of C20H26O4).

Dicyclohexyl phthalate (cas: 84-61-7) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. Acyl chlorides and acid anhydrides alcoholysis is another way to produce esters. Acyl chlorides and acid anhydrides react with alcohols to produce esters. Anydrous conditions are recommended since both acyl chlorides and acid anhydrides react with water.Synthetic Route of C20H26O4

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Peptide inhibitors of IκB protease: modification of the C-termini of Z-LLF-CHO was written by Suto, Mark J.;Sullivan, Robert W.;Ransone, Lynn J.. And the article was included in Bioorganic & Medicinal Chemistry Letters in 1996.Formula: C16H24N2O4 This article mentions the following:

A series of tripeptides (Z-Leu-Leu-Phe-R; where R is a modified C-terminus) were synthesized and evaluated for their ability to prevent the activation of NF-κB (nuclear factor κB) through the inhibition of IκB protease. Of the compounds evaluated, only the C-terminal aldehydes, Z-Leu-Leu-Phe-CHO and Z-Leu-Leu-D-Phe-CHO, were active in the Jurkat T-cell based assay. Z-Leu-Leu-Phe-CHO also decreased IL-2 and IL-8 levels in these cells indicating that inhibitors of IκB protease can have an effect on various signaling pathways. In the experiment, the researchers used many compounds, for example, (S)-tert-Butyl (1-(methoxy(methyl)amino)-1-oxo-3-phenylpropan-2-yl)carbamate (cas: 87694-53-9Formula: C16H24N2O4).

(S)-tert-Butyl (1-(methoxy(methyl)amino)-1-oxo-3-phenylpropan-2-yl)carbamate (cas: 87694-53-9) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. Many esters have the potential for conformational isomerism, but they tend to adopt an s-cis (or Z) conformation rather than the s-trans (or E) alternative, due to a combination of hyperconjugation and dipole minimization effects. The preference for the Z conformation is influenced by the nature of the substituents and solvent, if present. Lactones with small rings are restricted to the s-trans (i.e. E) conformation due to their cyclic structure.Formula: C16H24N2O4

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Elution behavior of a 3D-printed, milled and conventional resin-based occlusal splint material was written by Wedekind, Lennart;Gueth, Jan-Frederik;Schweiger, Josef;Kollmuss, Maximilian;Reichl, Franz-Xaver;Edelhoff, Daniel;Hoegg, Christof. And the article was included in Dental Materials in 2021.Application of 84-61-7 This article mentions the following:

The elution of unpolymerized (co-)monomers and additives from methacrylic resin-based materials like polymethyl methacrylate (PMMA) can cause adverse side effects, such as mutagenicity, teratogenicity, genotoxicity, cytotoxicity and estrogenic activity.The aim of this study was to quantify the release and the cytotoxicity of residual (co-)monomers and additives from PMMA-based splint materials under consideration of real splint sizes. Three different materials used for additive (3D printing), subtractive (milling) and conventional (powder and liquid) manufacturing were examinedThe splint materials SHERAprint-ortho plus (additive), SHERAeco-disk PM20 (subtractive) and SHERAORTHOMER (conventional) were analyzed. 16 (n = 4) sample disks of each material (6 mm diameter and 2 mm height) were polished on the circular and one cross-section area and then eluted in both distilled water and methanol. The disks were incubated at 37°C for 24 h or 72 h and subsequently analyzed by gas chromatog./mass spectrometry (GC/MS) for specifying and quantifying released compounds XTT-based cell viability assays with human gingival fibroblasts (HGFs) were performed for Tetrahydrofurfuryl methacrylate (THFMA), 1,4-Butylene glycol dimethacrylate (BDDMA) and Tripropylenglycol diacrylate (TPGDA). In order to project the disk size to actual splint sizes in a worst-case scenario, lower and upper jaw occlusal splints were designed and volumes and surfaces were measured.For SHERAeco-disk PM20 and for SHERAORTHOMER no elution was determined in water. SHERAprint-ortho plus eluted the highest THFMA concentration of 7.47μ mol/l ±2,77μmol/l after 72 h in water. Six (co-)monomers and five additives were detected in the methanol eluates of all three materials tested. The XTT-based cell viability assays resulted in a EC50 of 3006 ± 408μmol/l for THFMA, 2569.5 ± 308μmol/l for BDDMA and 596.7 ± 88μmol/l for TPGDA.With the solvent methanol, released components from the investigated splint materials exceeded cytotoxic concentrations in HGFs calculated for a worst-case scenario in splint size. In the water eluates only the methacrylate THFMA could be determined from SHERAprint-ortho plus in concentrations below cytotoxic levels in HGFs. In the experiment, the researchers used many compounds, for example, Dicyclohexyl phthalate (cas: 84-61-7Application of 84-61-7).

Dicyclohexyl phthalate (cas: 84-61-7) belongs to esters. Volatile esters with characteristic odours are used in synthetic flavours, perfumes, and cosmetics. Certain volatile esters are used as solvents for lacquers, paints, and varnishes. Because of their lack of hydrogen-bond-donating ability, esters do not self-associate. Consequently, esters are more volatile than carboxylic acids of similar molecular weight.Application of 84-61-7

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Exploiting urban roadside snowbanks as passive samplers of organic micropollutants and metals generated by traffic was written by Muller, Alexandra;Oesterlund, Helene;Marsalek, Jiri;Viklander, Maria. And the article was included in Environmental Pollution (Oxford, United Kingdom) in 2022.Formula: C20H26O4 This article mentions the following:

Stormwater and snowmelt runoff is known to contribute to the deterioration of quality of urban surface waters. Vehicular traffic is recognized as a major source of a wide range of pollutants to urban runoff, including conventional pollutants, such as suspended solids and metals, and those referred to as ‘contaminants of emerging concern ‘. The aim of this study was to investigate the contribution of selected metal(loid)s (Cd, Cr, Cu, Ni, Pb, Pd, Sb, W, Zn), polycyclic aromatic hydrocarbons (PAHs), nonylphenols, octylphenols and -ethoxylates, phthalates and bisphenol A (BPA) from vehicular traffic by sampling urban roadside snow at eight sites, with varying traffic intensities, and one control site without direct impacts of traffic. Our results confirmed that vehicles and traffic-related activities were the sources of octylphenols, BPA and phthalates as well as the metal(loid)s Sb and W, infrequently reported in previous studies. Among metal(loid)s, Cu, Zn and W occurred in the highest concentrations (up to 1.2 mg/L Cu, 2.4 mg/L Zn and 1.9 mg/L W), while PAHs and phthalates occurred in the highest concentrations among the trace organic pollutants (up to 540μg/L phthalate diisononyl phthalate). Among the phthalates, di-(2-ethylhexyl)phthalate had the highest frequency of detection (43% of the roadside samples). While BPA and octylphenols had relatively high frequencies of detection (50% for BPA and 81% for octylphenols), they were present in comparatively low concentrations (up to 0.2μg/L BPA and 1.1μg/L octylphenols). The control site displayed generally low concentrations of the pollutants studied, indicating that atm. deposition was not a significant source of the pollutants found in the roadside snow. Several of the pollutants in the roadside snow exceeded the applicable surface water and stormwater effluent guideline values. Thus, the transport of these pollutants with runoff posed risk of causing adverse effects in the receiving surface waters. In the experiment, the researchers used many compounds, for example, Dicyclohexyl phthalate (cas: 84-61-7Formula: C20H26O4).

Dicyclohexyl phthalate (cas: 84-61-7) belongs to esters. Volatile esters with characteristic odours are used in synthetic flavours, perfumes, and cosmetics. Certain volatile esters are used as solvents for lacquers, paints, and varnishes. Many esters have the potential for conformational isomerism, but they tend to adopt an s-cis (or Z) conformation rather than the s-trans (or E) alternative, due to a combination of hyperconjugation and dipole minimization effects. The preference for the Z conformation is influenced by the nature of the substituents and solvent, if present. Lactones with small rings are restricted to the s-trans (i.e. E) conformation due to their cyclic structure.Formula: C20H26O4

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

A comprehensive evaluation of organic micropollutants (OMPs) pollution and prioritization in equatorial lakes from mainland Tanzania, East Africa was written by Zhao, Zhonghua;Yao, Xiaolong;Ding, Qiqi;Gong, Xionghu;Wang, Jianjun;Tahir, Saadu;Kimirei, Ishmael Aaron;Zhang, Lu. And the article was included in Water Research in 2022.Synthetic Route of C20H26O4 This article mentions the following:

A lack of understanding the fate of highly toxic organic micropollutants (OMPs) in the equatorial lakes of Tanzania hinders public awareness for protecting these unique aquatic ecosystems, which are precious water resources and stunning wildlife habitats. To address this knowledge gap, the occurrence of 70 anthropogenically-sourced OMPs, including phthalates (PAEs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), was investigated in the water and sediment of 18 lakes in Tanzania. Similar residue concentrations were found in both compartments, showing higher pollution of PAEs ranging from 835.0 to 13,153.1 ng/L in water and 244.6-8691.8 ng/g dw in sediment, followed by PAHs, while OCPs and PCBs were comparatively lower. According to the multi-criteria scoring method for prioritization, the final OMP priority list for the lake environment in Tanzania comprised 25 chems., specifically 5 PAEs (DEHP, DIBP, DBP, DCHP and DMPP), 6 PCBs (PCB153, PCB105, PCB28, PCB156, PCB157 and PCB167), 6 PAHs (BaP, BaA, BbF, Pyr, DahA and InP) and 8 OCPs (cis-chlordane, trans-chlordane, p,p’-DDD, p,p’-DDE, p,p’-DDT, endrin, methoxychlor and heptachlor epoxide), suggesting the key substances for conventional monitoring and pollution control in these equatorial lakes, with an emphasis on PAEs, especially DEHP, due to the top priority and endocrine disruptor properties. In the experiment, the researchers used many compounds, for example, Dicyclohexyl phthalate (cas: 84-61-7Synthetic Route of C20H26O4).

Dicyclohexyl phthalate (cas: 84-61-7) belongs to esters. Esters are also usually derived from carboxylic acids. It may also be obtained by reaction of acid anhydride or acid halides with alcohols or by the reaction of salts of carboxylic acids with alkyl halides. Liquid esters of low volatility serve as softening agents for resins and plastics. Esters also include many industrially important polymers. Polymethyl methacrylate is a glass substitute sold under the names Lucite and Plexiglas; polyethylene terephthalate is used as a film (Mylar) and as textile fibres sold as Terylene, Fortrel, and Dacron.Synthetic Route of C20H26O4

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Copper-Catalyzed Anomeric O-Arylation of Carbohydrate Derivatives at Room Temperature was written by Verdelet, Tristan;Benmahdjoub, Sara;Benmerad, Belkacem;Alami, Mouad;Messaoudi, Samir. And the article was included in Journal of Organic Chemistry in 2019.Synthetic Route of C16H22O11 This article mentions the following:

Direct and practical anomeric O-arylation of sugar lactols with substituted arylboronic acids has been established. Using copper catalysis at room temperature under an air atm., the protocol proved to be general, and a variety of aryl O-glycosides have been prepared in good to excellent yields. Furthermore, this approach was extended successfully to unprotected carbohydrates, including α-mannose, and it was demonstrated here how the interaction between carbohydrates and boronic acids can be combined with copper catalysis to achieve selective anomeric O-arylation. In the experiment, the researchers used many compounds, for example, (2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate (cas: 4163-60-4Synthetic Route of C16H22O11).

(2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate (cas: 4163-60-4) belongs to esters. Esters are also usually derived from carboxylic acids. It may also be obtained by reaction of acid anhydride or acid halides with alcohols or by the reaction of salts of carboxylic acids with alkyl halides. Many esters have the potential for conformational isomerism, but they tend to adopt an s-cis (or Z) conformation rather than the s-trans (or E) alternative, due to a combination of hyperconjugation and dipole minimization effects. The preference for the Z conformation is influenced by the nature of the substituents and solvent, if present. Lactones with small rings are restricted to the s-trans (i.e. E) conformation due to their cyclic structure.Synthetic Route of C16H22O11

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Concise Synthesis of 1-Thioalkyl Glycoside Donors by Reaction of Per-O-acetylated Sugars with Sodium Alkanethiolates under Solvent-Free Conditions was written by Feng, Guang-Jing;Luo, Tao;Guo, Yang-Fan;Liu, Chun-Yang;Dong, Hai. And the article was included in Journal of Organic Chemistry.Quality Control of (2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate This article mentions the following:

A relatively green method for synthesizing 1-thioalkyl glycosides has been developed, where sodium alkanethiolates were used to react with per-O-acetylated sugars instead of odorous alkyl mercaptans in the presence of BF₃·Et₂O without the use of solvents under mild conditions. Furthermore, we found that 1,2-trans-β-thioglycosides can be converted into corresponding 1,2-cis-α-thioglycosides in the presence of trifluoromethanesulfonic acid in nonpolar solvents under mild conditions. This provides a simple and efficient new approach for synthesizing challenging 1,2-cis-α-thioglycosides. In the experiment, the researchers used many compounds, for example, (2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate (cas: 4163-60-4Quality Control of (2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate).

(2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate (cas: 4163-60-4) belongs to esters. Esters are widespread in nature and are widely used in industry. In nature, fats are in general triesters derived from glycerol and fatty acids. Esters are responsible for the aroma of many fruits, including apples, durians, pears, bananas, pineapples, and strawberries. Because of their lack of hydrogen-bond-donating ability, esters do not self-associate. Consequently, esters are more volatile than carboxylic acids of similar molecular weight.Quality Control of (2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Making of water soluble curcumin to potentiate conventional antimicrobials by inducing apoptosis-like phenomena among drug-resistant bacteria was written by Yadav, Shivangi;Singh, Ashish Kumar;Agrahari, Anand Kumar;Sharma, Kavyanjali;Singh, Anoop Shyam;Gupta, Munesh Kumar;Tiwari, Vinod Kumar;Prakash, Pradyot. And the article was included in Scientific Reports in 2020.Application In Synthesis of (2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate This article mentions the following:

The upsurge of multidrug resistant bacterial infections with declining pipeline of newer antibiotics has made it imperative to develop newer mols. or tailor the existing mols. for more effective antimicrobial therapies. Since antiquity, the use of curcumin, in the form of Curcuma longa paste, to treat infectious lesions is unperturbed despite its grave limitations like instability and aqueous insolubility Here, we utilized “click” chem. to address both the issues along with improvisation of its antibacterial and antibiofilm profile. We show that soluble curcumin disrupts several bacterial cellular processes leading to the Fenton′s chem. mediated increased production of reactive oxygen species and increased membrane permeability of both Gram-pos. and Gram-neg. bacteria. We here report that its ability to induce oxidative stress can be harnessed to potentiate activities of ciprofloxacin, meropenem, and vancomycin. In addition, we demonstrated that the soluble curcumin reported herein even sensitizes resistant Gram-neg. clin. isolates to the Gram-pos. specific antibiotic vancomycin, thereby expanding the antibacterial spectrum of this drug. This work shows that the soluble curcumin can be used to enhance the action of existing antimicrobials against both Gram-pos. and Gram-neg. bacteria thus strengthening the antibiotic arsenal for fighting resistant bacterial infections for many years to come. In the experiment, the researchers used many compounds, for example, (2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate (cas: 4163-60-4Application In Synthesis of (2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate).

(2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate (cas: 4163-60-4) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. Esters are more polar than ethers but less polar than alcohols. They participate in hydrogen bonds as hydrogen-bond acceptors, but cannot act as hydrogen-bond donors, unlike their parent alcohols. This ability to participate in hydrogen bonding confers some water-solubility.Application In Synthesis of (2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Reduction effects of solar radiation, mechanical tension, and soil burial on phthalate esters concentrations in plastic film and soils was written by Wang, Dong;Xi, Yue;Shi, Xiao-Yan;Han, Ya-Nan;Zhang, Ning;Ahmad, Farhan;Li, Feng-Min. And the article was included in Science of the Total Environment in 2021.Safety of Dicyclohexyl phthalate This article mentions the following:

Phthalate esters (PAEs) are potentially dangerous chems. in plastic film mulched fields; however, few studies have investigated how to reduce their concentrations in plastic film and soil. In this study, the effects of solar radiation, mech. tension, and soil burial on PAEs concentrations in polyethylene (PE) film and degradable film were investigated, and the half-lives of di-Bu phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP) in soil also studied. PAEs concentrations in polyethylene films were about twice those in the degradable films; however, PAEs concentrations in all exptl. films were similar after 1-yr of field exposure. Mech. tension had no effect on the PAEs concentrations of polyethylene films, but increased the detected concentrations of PAEs in degradable films by 34%-120%. After 4-years of burial, the PAEs concentrations in films decreased by 79.2%-98.0%, and mech. tension promoted the reductions However, there was little difference in PAEs concentrations between the buried soils with and without films, indicating the released PAEs reduced quickly in soil. Also, the half-lives of DBP and DEHP were 2.4-4.6 days and 18.5-41.4 days, resp. Overall, the results presented herein provide reasonable approaches to reduce the concentrations of PAEs in plastic films and soils. In the experiment, the researchers used many compounds, for example, Dicyclohexyl phthalate (cas: 84-61-7Safety of Dicyclohexyl phthalate).

Dicyclohexyl phthalate (cas: 84-61-7) belongs to esters. Esters typically have a pleasant smell; those of low molecular weight are commonly used as fragrances and are found in essential oils and pheromones. Esterification is the general name for a chemical reaction in which two reactants (typically an alcohol and an acid) form an ester as the reaction product. Esters are common in organic chemistry and biological materials.Safety of Dicyclohexyl phthalate

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Degradation of PVA wastewater by Cu_xMn_xFe_3-2xO₄/MWCNT catalyst was written by Zhang, Yue;Zhu, Gaofeng;Ge, Mingqiao. And the article was included in Journal of Materials Science: Materials in Electronics in 2021.Synthetic Route of C20H26O4 This article mentions the following:

Cu_xMn_xFe_3-2xO₄/MWCNT nanocomposites were prepared by co-precipitation method. The structure, morphol., and surface properties of the samples were characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM), Energy dispersive spectrometer (EDS), Fourier transform IR spectrometer (FTIR), N2 phys. adsorption instrument, and X-ray photoelectron spectrometer (XPS). The successful loading of metal oxides on MWCNTs increased the catalytic activity of nanocomposites. In addition, CuxMnxFe3-2xO4/MWCNTs were used as catalyst for the degradation of PVA wastewater by catalytic wet air oxidation Under the degradation conditions, pH was 2.5, catalyst dosage was1.5 g/L, reaction temperature was 275 °C, oxygen pressure was 1.0MP, the PVA degradation rate was 99.94%, the viscosity average mol. weight was decreased by 99.36%, and the degradation products were small mols. such as aldehydes, phenols, and acids, which basically confirmed the degradation of PVA wastewater. The degradation principle and kinetics were analyzed. The catalyst was washed and recovered and can maintain good catalytic capacity after four times of repeated use. In the experiment, the researchers used many compounds, for example, Dicyclohexyl phthalate (cas: 84-61-7Synthetic Route of C20H26O4).

Dicyclohexyl phthalate (cas: 84-61-7) belongs to esters. Esters are widespread in nature and are widely used in industry. In nature, fats are in general triesters derived from glycerol and fatty acids. Esters are responsible for the aroma of many fruits. Cyclic esters are called lactones, regardless of whether they are derived from an organic or inorganic acid. One example of an organic lactone is γ-valerolactone.Synthetic Route of C20H26O4

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics