Month: November 2022

On November 30, 1987, Roberts, D. W. published an article.SDS of cas: 1985-51-9 The title of the article was Structure-activity relationships for skin sensitization potential of diacrylates and dimethacrylates. And the article contained the following:

Apparently conflicting guinea pig sensitization data on diacrylates and dimethacrylates, published by 3 groups of authors, are analyzed in terms of the relative alkylation index model. This model, correlating sensitization score with a combination of induction dose, chem. reactivity, and lipophilicity, enables the major discrepancies to be rationalized. The data provide a striking example of the overload effect, in that some of the diacrylates have failed to show sensitization when tested at high induction doses, but are revealed as strong sensitizers when tested by other authors at lower induction doses. The experimental process involved the reaction of 2,2-Dimethylpropane-1,3-diyl bis(2-methylacrylate)(cas: 1985-51-9).SDS of cas: 1985-51-9

The Article related to mol structure sensitization acrylate methacrylate, allergy diacrylate dimethacrylate mol structure, Toxicology: Chemicals (Household, Industrial, General) and other aspects.SDS of cas: 1985-51-9

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

On August 1, 2000, Nishihara, Tsutomu; Nishikawa, Junichi; Kanayama, Tomohiko; Dakeyama, Fumi; Saito, Koichi; Imagawa, Masayoshi; Takatori, Satoshi; Kitagawa, Yoko; Hori, Shinjiro; Utsumi, Hideo published an article.COA of Formula: C13H20O4 The title of the article was Estrogenic activities of 517 chemicals by yeast two-hybrid assay. And the article contained the following:

One of the urgent tasks in understanding endocrine disruptors (EDs) is to compile a list of suspected substances among the huge number of chems. by using the screening test method. We developed a simple and rapid screening method using the yeast two-hybrid system based on the ligand-dependent interaction of nuclear hormone receptors with coactivators. To date, we have tested the estrogenic activity of more than 500 chems. including natural substances, medicines, pesticides, and industrial chems. Sixty-four compounds were evaluated as pos., and most of these demonstrated a common structure; phenol with a hydrophobic moiety at the para-position without bulky groups at the ortho-position. These results are expected to facilitate further risk assessment of chems. The experimental process involved the reaction of 2,2-Dimethylpropane-1,3-diyl bis(2-methylacrylate)(cas: 1985-51-9).COA of Formula: C13H20O4

The Article related to estrogenic activity chem substance risk assessment, endocrine disruptor risk assessment yeast assay, Toxicology: Chemicals (Household, Industrial, General) and other aspects.COA of Formula: C13H20O4

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

McCombie, Gregor; Biedermann, Sandra; Suter, Gaby; Biedermann, Maurus published an article in 2017, the title of the article was Survey on plasticizers currently found in PVC toys on the Swiss market: Banned phthalates are only a minor concern.Quality Control of Tris(2-ethylhexyl) benzene-1,2,4-tricarboxylate And the article contains the following content:

Plasticizers in toys are a recurring source of criticism and concern, as consumers feel they may endanger the health of their children. Most of the information available in literature concerns the presence or absence of certain phthalic acid ester plasticizers. Very little information can be found in the public domain with respect to the actually used plasticizers at a given time and place. In this paper, we present the plasticizer composition of 118 samples from 88 polyvinyl chloride toys found on the Swiss market in autumn 2015. Bis(2-ethylhexyl) terephthalate (DEHT) was by far the most frequent main plasticizer in the analyzed samples, which is a change when compared to the plasticizers found in toys and child care articles in 2007. Furthermore, the data show that the banned phthalates in toys are only a minor concern. The occurrence, however, is not evenly distributed between importers. If a toy is not designed to be sold on the European market by the manufacturer, it seems to be more likely to contain a banned phthalic acid ester. The experimental process involved the reaction of Tris(2-ethylhexyl) benzene-1,2,4-tricarboxylate(cas: 3319-31-1).Quality Control of Tris(2-ethylhexyl) benzene-1,2,4-tricarboxylate

The Article related to plasticizer phthalate polyvinyl chloride switzerland, dehp, pvc, phthalates, plasticizers, toy safety, Toxicology: Chemicals (Household, Industrial, General) and other aspects.Quality Control of Tris(2-ethylhexyl) benzene-1,2,4-tricarboxylate

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

On January 31, 1983, Van der Walle, H. B.; Waegemaekers, T.; Bensink, T. published an article.HPLC of Formula: 1985-51-9 The title of the article was Sensitizing potential of 12 di(meth)acrylates in the guinea pig. And the article contained the following:

The sensitizing potential of 12 di(meth)acrylates was investigated in the Guinea Pig Maximization Test and Freund’s Complete Adjuvant Test (FCAT). In these tests, the same (molar) concentration was used for intradermal induction. Dimethacrylates were moderate to strong sensitizers in the guinea pig. In diacrylates, no sensitization to diethylene glycol diacrylate  [4074-88-8] was observed 1,2-ethanediol diacrylate  [2274-11-5] And 1,6-hexanediol diacrylate  [13048-33-4] sensitized a number of animals. The challenge reaction pattern of the FCAT with 1,4-butanediol diacrylate  [1070-70-8], neopentanediol diacrylate  [2223-82-7] and 5-pentanediol diacrylate  [36840-85-4] differed form that commonly observed with sensitizers. Pos. reactions were seen only to the maximum nonirritant concentration at 24 h in the challenge at day 21. At 48 h and in the 2nd challenge at day 35, the reactivity had decreased or disappeared. This different reaction pattern made it difficult to classify these monomers with certainty as sensitizers. In most of the FCATs, a decrease in reactivity in successive challenges was found. Possible explanations for this decrease and for the different challenge reaction patterns of some diacrylates were discussed. The skin irritant capacity of di(meth)acrylates was estimated after 1 open application. Diacrylates were very strong irritants on guinea pig skin. Dimethacrylates were weak irritants. The experimental process involved the reaction of 2,2-Dimethylpropane-1,3-diyl bis(2-methylacrylate)(cas: 1985-51-9).HPLC of Formula: 1985-51-9

The Article related to dimethacrylate allergy, skin irritation methacrylate, acrylate allergy, sensitization skin acrylate methacrylate, Toxicology: Chemicals (Household, Industrial, General) and other aspects.HPLC of Formula: 1985-51-9

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

On August 31, 2020, Pannala, Venkat R.; Estes, Shanea K.; Rahim, Mohsin; Trenary, Irina; O’Brien, Tracy P.; Shiota, Chiyo; Printz, Richard L.; Reifman, Jaques; Oyama, Tatsuya; Shiota, Masakazu; Young, Jamey D.; Wallqvist, Anders published an article.Recommanded Product: (R)-Methyl 3-hydroxybutanoate The title of the article was Mechanism-based identification of plasma metabolites associated with liver toxicity. And the article contained the following:

Early diagnosis of liver injuries caused by drugs or occupational exposures is necessary to enable effective treatments and prevent liver failure. Whereas histopathol. remains the gold standard for assessing hepatotoxicity in animals, plasma aminotransferase levels are the primary measures for monitoring liver dysfunction in humans. In this study, using Sprague Dawley rats, we investigated whether integrated analyses of transcriptomic and metabolomic data with genome-scale metabolic models (GSMs) could identify early indicators of injury and provide new insights into the mechanisms of hepatotoxicity. We obtained concurrent measurements of gene-expression changes in the liver and kidneys, and expression changes along with metabolic profiles in the plasma and urine, from rats 5 or 10 h after exposing them to one of two classical hepatotoxicants, acetaminophen (2 g/kg) or bromobenzene (0.4 g/kg). Global multivariate analyses revealed that gene-expression changes in the liver and metabolic profiles in the plasma and urine of toxicant-treated animals differed from those of controls, even at time points much earlier than changes detected by conventional markers of liver injury. Furthermore, clustering anal. revealed that both the gene-expression changes in the liver and the metabolic profiles in the plasma induced by the two hepatotoxicants were highly correlated, indicating commonalities in the liver toxicity response. Systematic GSM-based analyses yielded metabolites associated with the mechanisms of toxicity and identified several lipid and amino acid metabolism pathways that were activated by both toxicants and those uniquely activated by each. Our findings suggest that several metabolite alterations, which are strongly associated with the mechanisms of toxicity and occur within injury-specific pathways (e.g., of bile acid and fatty acid metabolism), could be targeted and clin. assessed for their potential as early indicators of liver damage. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Recommanded Product: (R)-Methyl 3-hydroxybutanoate

The Article related to plasma metabolite liver toxicity, acetaminophen, biomarker, bromobenzene, genome-scale models, hepatotoxicants, pathways, Toxicology: Chemicals (Household, Industrial, General) and other aspects.Recommanded Product: (R)-Methyl 3-hydroxybutanoate

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

On January 31, 2016, Fromme, H.; Schuetze, A.; Lahrz, T.; Kraft, M.; Fembacher, L.; Siewering, S.; Burkardt, R.; Dietrich, S.; Koch, H. M.; Voelkel, W. published an article.HPLC of Formula: 3319-31-1 The title of the article was Non-phthalate plasticizers in German daycare centers and human biomonitoring of DINCH metabolites in children attending the centers (LUPE 3). And the article contained the following:

Plasticizers have been widely used for decades as additives in diverse applications, including consumer and building products, toys, cables, and floorings. Due to toxicol. concerns and restrictions of different dialkyl ortho-phthalates, other plasticizers have been increasingly used in recent years. Therefore, di-isononyl cyclohexane-1,2-dicarboxylate (DINCH), di(2-ethylhexyl) terephthalate (DEHT), di(2-ethylhexyl) adipate (DEHA), acetyl tri-Bu citrate (ATBC), and trioctyl trimellitate (TOTM) plasticizer levels in indoor air and dust samples from 63 daycare centers in Germany were measured. Moreover, the urine samples of 208 children who attend 27 of these facilities were analyzed for the presence of four DINCH metabolites.DINCH, DEHT, and DEHA were present in indoor air with median values of 108 ng/m3, 20 ng/m3, and 34 ng/m3, resp. Median values of 302 mg/kg for DINCH, 49 mg/kg for DEHA, 40 mg/kg for DEHT, and 24 mg/kg ATBC were found in dust. In the urine samples, the three secondary metabolites of DINCH were observed with median values (95th percentiles) of 1.7 μg/l (10.0 μg/l) for OH-MINCH, 1.5 μg/l (8.0 μg/l) for oxo-MINCH, and 1.1 μg/l (6.1 μg/l) for cx-MINCH. Overall, these metabolite levels are orders of magnitude lower than the current HBM I values set by the German Human Biomonitoring Commission.Using general exposure assumptions, the intake resulting from dust ingestion and inhalation is low for children. The total daily DINCH intake calculated from biomonitoring data was 0.5 μg/kg b.w. using median values and 9.8 μg/kg b.w. as the maximum value. At present, non-phthalate plasticizers, especially DINCH, can be found in considerable amounts in dust samples from daycare centers and as DINCH metabolites in the urine of children. In relation to previous studies, the concentrations of DINCH in dust and urine have an increasing time trend. Compared with tolerable daily intake values, the total daily intake of DINCH reached only 1% of its maximum value to date; however, due to its increased use, higher exposure of DINCH is expected in the future. The experimental process involved the reaction of Tris(2-ethylhexyl) benzene-1,2,4-tricarboxylate(cas: 3319-31-1).HPLC of Formula: 3319-31-1

The Article related to nonphthalate plasticizer dinch urine germany, deha, deht, dinch, daycare centers, human biomonitoring, indoor air, plasticizer, Toxicology: Chemicals (Household, Industrial, General) and other aspects.HPLC of Formula: 3319-31-1

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

On September 30, 2018, Hoellerer, Christine; Becker, Guenther; Goeen, Thomas; Eckert, Elisabeth published an article.SDS of cas: 3319-31-1 The title of the article was Human metabolism and kinetics of tri-(2-ethylhexyl) trimellitate (TEHTM) after oral administration. And the article contained the following:

Tri-(2-ethylhexyl) trimellitate (TEHTM) is a plasticizer for PVC material and is used for medical devices as an alternative to di-(2-ethylhexyl) phthalate. As plasticizers are known to migrate easily into contact liquids, exposure of patients to TEHTM is highly probable. In the present study, human metabolism pathways of TEHTM and its elimination kinetics were investigated. For that purpose, four healthy volunteers were orally exposed to a single dose of TEHTM. TEHTM and its postulated primary metabolites were investigated in blood samples (up to 48 h after exposure), and in urine samples (collected until 72 h after exposure) using liquid chromatog. tandem mass spectrometry (LC-MS/MS). TEHTM was found to be regioselectively hydrolyzed to its diesters di-2-(ethylhexyl) trimellitates (1,2-DEHTM, 2,4-DEHTM) with maximum blood concentrations at 3-h post-exposure, and to its monoester isomers mono-2-(ethylhexyl) trimellitates (1-MEHTM, 2-MEHTM) with peak blood concentrations 5-h post-exposure. For the elimination of investigated urinary metabolites, biphasic elimination kinetics was observed The most dominant urinary biomarker was found to be 2-MEHTM (2-mono-(2-ethylhexyl) trimellitate), followed by several specific secondary metabolites. All in all, approx. 5.8% of the orally administered dose was recovered in urine over a period of 72 h, indicating a comparatively low resorption rate of TEHTM in humans in combination with an apparently rather slow metabolism and excretion rate. In fact, TEHTM and selected metabolites were still detectable in blood and urine 48-h and 72-h post-exposure, resp. This study is the first to elucidate TEHTM metabolism pathways in humans and to identify metabolites of TEHTM in blood and urine by usage of especially designed human biomonitoring methods. Powerful tools for exposure monitoring and risk assessment of TEHTM are therewith available for future research. The experimental process involved the reaction of Tris(2-ethylhexyl) benzene-1,2,4-tricarboxylate(cas: 3319-31-1).SDS of cas: 3319-31-1

The Article related to metabolism kinetics tehtm, biomonitoring, elimination kinetics, human metabolism, plasticizers, tri-(2-ethylhexyl) trimellitate, Toxicology: Chemicals (Household, Industrial, General) and other aspects.SDS of cas: 3319-31-1

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

On June 30, 2009, Ren, Sumei; McNamara, Paul; Koharski, David; Hesk, David; Borges, Scott published an article.Category: esters-buliding-blocks The title of the article was Design and synthesis of sulfur-35 agents and their applications for protein labeling. And the article contained the following:

Two new 35S reagents were developed to radiolabel proteins. The first reagent, SMSB (I), acylates the ε-amino group of lysine residues in proteins. The second reagent, MSAPPA (II), labels lysine residues via reductive alkylation. Comparing the two methods, the reductive alkylation method labeled proteins over a broader pH range with higher overall radiochem. yield. More than ten monoclonal antibodies (mAbs) have been labeled with these 35S labeling reagents, the biol. activity of the mAbs was unchanged. The experimental process involved the reaction of tert-Butyl 4-((((benzyloxy)carbonyl)amino)methyl)benzoate(cas: 220851-46-7).Category: esters-buliding-blocks

The Article related to monoclonal antibody 35s radiolabeled preparation, radiolabel smsb msappa preparation acylation reductive alkylation lysine protein, Amino Acids, Peptides, and Proteins: Protein Synthesis and other aspects.Category: esters-buliding-blocks

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

On March 31, 2018, Hoellerer, Christine; Becker, Guenther; Goeen, Thomas; Eckert, Elisabeth published an article.Electric Literature of 3319-31-1 The title of the article was Regioselective ester cleavage of di-(2-ethylhexyl) trimellitates by porcine liver esterase. And the article contained the following:

In a comparative study the ester hydrolysis of the plasticizers di-(2-ethylhexyl) phthalate (DEHP) and tri-(2-ethylhexyl) trimellitate (TEHTM) as well as of the diester isomers 1,2-di-(2-ethylhexyl) trimellitate (1,2-DEHTM), 1,4-di-(2-ethylhexyl) trimellitate (1,4-DEHTM) and 2,4-di-(2-ethylhexyl) trimellitate (2,4-DEHTM) was investigated by a newly developed in vitro exptl. using porcine liver esterase (PLE). The substrates were incubated with PLE for 48 h at 25° in borate buffer and samples were taken at predetermined intervals during the experiment The samples were processed using liquid-liquid extraction and analyzed using LC-MS/MS. The results demonstrated a rapid and extensive hydrolysis of the diester DEHP to the monoester mono-(2-ethylhexyl) phthalate (MEHP) during the incubation with PLE. The isomers of DEHTM were also hydrolyzed by PLE to a high extent, whereas TEHTM showed a high stability against enzymic hydrolysis. The regioselective anal. revealed that the monoester isomers 1-MEHTM and 2-MEHTM were predominantly produced during the degradation of DEHTM isomers, indicating a preferred hydrolysis at the para-position. These findings are eminent for planning further investigations on the human TEHTM metabolism, as the extent, rate and route of metabolism are of crucial importance for a toxicol. assessment. The experimental process involved the reaction of Tris(2-ethylhexyl) benzene-1,2,4-tricarboxylate(cas: 3319-31-1).Electric Literature of 3319-31-1

The Article related to pig liver esterase dehp tehtm dehtm, di-(2-ethylhexyl) phthalate, metabolism, porcine liver esterase, tri-(2-ethylhexyl) trimellitate, Toxicology: Chemicals (Household, Industrial, General) and other aspects.Electric Literature of 3319-31-1

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

Kambia, Nicolas; Farce, Amaury; Belarbi, Karim; Gressier, Bernard; Luyckx, Michel; Chavatte, Philippe; Dine, Thierry published an article in 2016, the title of the article was Docking study: PPARs interaction with the selected alternative plasticizers to di(2-ethylhexyl) phthalate.COA of Formula: C33H54O6 And the article contains the following content:

Phthalates, used in medical devices (MDs), have been identified as reproductive and developmental toxicants. Their toxicity varies somewhat depending on the specific phthalate and is in part linked to the activation of Peroxisome Proliferating-Activated Receptors (PPARs). So, the use of MDs containing targeted phthalates such as di(2-ethylhexyl) phthalate (DEHP) has been challenged by European directive 2007/47/EC. Therefore, MDs manufacturers were forced to quickly find replacement plasticizers. However, very little toxicol. and epidemiol. studies are available on human health. So, we proceeded to dock these chems. in order to identify compounds that are likely to interact with PPARs binding sites. The results obtained are generally very mixed on the harmlessness of these alternatives. Moreover, no data exist on the biol. effects of their possible metabolites. As DEHP toxicity resulted mainly from its major metabolites, generalizing the use of these plasticizers without conducting extensive studies on the possible effects on human health of their metabolites seems inconceivable. The experimental process involved the reaction of Tris(2-ethylhexyl) benzene-1,2,4-tricarboxylate(cas: 3319-31-1).COA of Formula: C33H54O6

The Article related to dehp alternative plasticizer ppar interaction docking, alternative plasticizers, ppars, docking, medical devices, toxicological action, Toxicology: Chemicals (Household, Industrial, General) and other aspects.COA of Formula: C33H54O6

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