Nie, Shenyou et al. published their research in Journal of Medicinal Chemistry in 2021 | CAS: 330794-35-9

tert-Butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzylcarbamate (cas: 330794-35-9) 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. 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.Reference of 330794-35-9

Synthesis, Structure-Activity Relationships, and Antiviral Activity of Allosteric Inhibitors of Flavivirus NS2B-NS3 Protease was written by Nie, Shenyou;Yao, Yuan;Wu, Fangrui;Wu, Xiaowei;Zhao, Jidong;Hua, Yuanda;Wu, Jingyu;Huo, Tong;Lin, Yi-Lun;Kneubehl, Alexander R.;Vogt, Megan B.;Ferreon, Josephine;Rico-Hesse, Rebecca;Song, Yongcheng. And the article was included in Journal of Medicinal Chemistry in 2021.Reference of 330794-35-9 This article mentions the following:

Flaviviruses, including Zika, dengue, and West Nile viruses, are important human pathogens. The highly conserved NS2B-NS3 protease of Flavivirus is essential for viral replication and therefore a promising drug target. Through compound screening, followed by medicinal chem. studies, a novel series of 2,5,6-trisubstituted pyrazine compounds are found to be potent, allosteric inhibitors of Zika virus protease (ZVpro) with IC50 values as low as 130 nM. Their structure-activity relationships are discussed. The ZVpro inhibitors also inhibit homologous proteases of dengue and West Nile viruses, and their inhibitory activities are correlated. The most potent compounds 47 and 103 potently inhibited Zika virus replication in cells with EC68 values of 300-600 nM and in a mouse model of Zika infection. These compounds represent novel pharmacol. leads for drug development against Flavivirus infections. In the experiment, the researchers used many compounds, for example, tert-Butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzylcarbamate (cas: 330794-35-9Reference of 330794-35-9).

tert-Butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzylcarbamate (cas: 330794-35-9) 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. 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.Reference of 330794-35-9

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

Wen, Zina et al. published their research in Ecotoxicology and Environmental Safety in 2021 | CAS: 84-61-7

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, including apples, durians, pears, bananas, pineapples, and strawberries. Esters contain a carbonyl center, which gives rise to 120° C–C–O and O–C–O angles. Unlike amides, esters are structurally flexible functional groups because rotation about the C–O–C bonds has a low barrier. Their flexibility and low polarity is manifested in their physical properties; they tend to be less rigid (lower melting point) and more volatile (lower boiling point) than the corresponding amides. Name: Dicyclohexyl phthalate

Inhibition of human sperm motility and capacitation by ziram is mediated by decreasing tyrosine protein kinase was written by Wen, Zina;Lei, Zhen;Tian, Erpo;Wang, Yiyan;Zhong, Ying;Ge, Ren-shan. And the article was included in Ecotoxicology and Environmental Safety in 2021.Name: Dicyclohexyl phthalate This article mentions the following:

Many endocrine disruptors may interfere with sperm motility, hyperactivation, and capacitation, thereby leading to male infertility. In the current study, we screened 14 endocrine disruptors, including plant ingredients, cigarette ingredients, minerals, insecticides and fungicides, plastics, and plasticizers, to inhibit human sperm motility and forward motility. Only ziram, a dithiocarbamate fungicide, can effectively inhibit sperm motility, forward motility, hyperactivation, capacitation, and spontaneous acrosome reaction of normal human spermatozoa. Its half maximum inhibitory concentration (IC50) values were less than 4μM. Ziram also inhibited sperm motility and forward motility of asthenozoospermia spermatozoa and IC50 values were about 6-8μM. In addition, ziram inhibited normal sperm motility, calcium influx, reactive oxygen species, and mitochondrial membrane potential at 2.5 and/or 5μM, with IC50 values exceeding 100μM, although it did not affect sperm DNA fragmentation up to 5μM. Ziram-mediated inhibition of sperm motility and forward motility was irreversible. Forskolin, 8Br-cAMP, pentoxifylline, progesterone, vitamin E, and A23187 cannot prevent ziram-mediated inhibition of sperm motility and forward motility. Further studies have shown that ziram inhibited the level of tyrosine protein kinase with an IC50 value of about 10μM, without affecting p21-activated kinase 4, and it caused damage to the mitochondrial structure of normal spermatozoa at 2.5 and 5μM. In conclusion, ziram irreversibly inhibits human sperm motility, forward motility, and capacitation by reducing the level of tyrosine protein kinase and damaging the ultrastructure of mitochondria. In the experiment, the researchers used many compounds, for example, Dicyclohexyl phthalate (cas: 84-61-7Name: Dicyclohexyl phthalate).

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, including apples, durians, pears, bananas, pineapples, and strawberries. Esters contain a carbonyl center, which gives rise to 120° C–C–O and O–C–O angles. Unlike amides, esters are structurally flexible functional groups because rotation about the C–O–C bonds has a low barrier. Their flexibility and low polarity is manifested in their physical properties; they tend to be less rigid (lower melting point) and more volatile (lower boiling point) than the corresponding amides. Name: Dicyclohexyl phthalate

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

Diegelmann, Stephen R. et al. published their research in Journal of the American Chemical Society in 2008 | CAS: 19432-68-9

Methyl 2-thienylacetate (cas: 19432-68-9) 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.COA of Formula: C7H8O2S

One-dimensional optoelectronic nanostructures derived from the aqueous self-assembly of π-conjugated oligopeptides was written by Diegelmann, Stephen R.;Gorham, Justin M.;Tovar, John D.. And the article was included in Journal of the American Chemical Society in 2008.COA of Formula: C7H8O2S This article mentions the following:

The aqueous self-assembly of oligopeptide-flanked π-conjugated mols. into discrete one-dimensional nanostructures is described. Unique to these mols. is the fact that the π-conjugated unit has been directly embedded within the peptide backbone by way of a synthetic amino acid with π-functionality that is compatible with standard Fmoc-based (Fmoc = 9-fluorenylmethoxycarbonyl) peptide synthesis. The peptide-based mol. design enforces intimate π-π communication within the aggregate after charge-screening and self-assembly, making these nanostructures attractive for optical or electronic applications in biol. environments. The synthesis and assembly are reported along with spectroscopic and morphol. characterization of the new nanomaterials. In the experiment, the researchers used many compounds, for example, Methyl 2-thienylacetate (cas: 19432-68-9COA of Formula: C7H8O2S).

Methyl 2-thienylacetate (cas: 19432-68-9) 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.COA of Formula: C7H8O2S

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

Chen, Xing et al. published their research in Journal of Organic Chemistry in 2011 | CAS: 13669-10-8

Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8) 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. 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.Quality Control of Ethyl 3-oxo-3-(thiophen-2-yl)propanoate

Enantioselective synthesis of 4-substituted 4,5-dihydro-1H-[1,5]benzodiazepin-2(3H)-ones by the Lewis base-catalyzed hydrosilylation was written by Chen, Xing;Zheng, Yongsheng;Shu, Chang;Yuan, Weicheng;Liu, Bo;Zhang, Xiaomei. And the article was included in Journal of Organic Chemistry in 2011.Quality Control of Ethyl 3-oxo-3-(thiophen-2-yl)propanoate This article mentions the following:

Enantioselective synthesis of 4-substituted 4,5-dihydro-1H-[1,5]benzodiazepin-2(3H)-ones has been accomplished through chiral Lewis base-catalyzed hydrosilylation. The corresponding products were obtained in excellent yields (up to 99%) and enantioselectivities (up to 98%). The absolute configuration of product I has been determined as S by X-ray crystallog. anal. In the experiment, the researchers used many compounds, for example, Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8Quality Control of Ethyl 3-oxo-3-(thiophen-2-yl)propanoate).

Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8) 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. 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.Quality Control of Ethyl 3-oxo-3-(thiophen-2-yl)propanoate

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

Chen, Yin et al. published their research in Journal of Medicinal Chemistry in 2013 | CAS: 13669-10-8

Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8) 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. 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.Recommanded Product: Ethyl 3-oxo-3-(thiophen-2-yl)propanoate

Synthesis and Biological Investigation of Coumarin Piperazine (Piperidine) Derivatives as Potential Multireceptor Atypical Antipsychotics was written by Chen, Yin;Wang, Songlin;Xu, Xiangqing;Liu, Xin;Yu, Minquan;Zhao, Song;Liu, Shicheng;Qiu, Yinli;Zhang, Tan;Liu, Bi-Feng;Zhang, Guisen. And the article was included in Journal of Medicinal Chemistry in 2013.Recommanded Product: Ethyl 3-oxo-3-(thiophen-2-yl)propanoate This article mentions the following:

The discovery and synthesis of potential and novel antipsychotic coumarin derivatives, associated with potent dopamine D2, D3, and serotonin 5-HT1A and 5-HT2A receptor properties, are the focus of the present article. The most-promising derivative was 7-(4-(4-(6-fluorobenzo[d]isoxazol-3-yl)-piperidin-1-yl)butoxy)-4-methyl-8-chloro-2H-chromen-2-one (I). This derivative possesses unique pharmacol. features, including high affinity for dopamine D2 and D3 and serotonin 5-HT1A and 5-HT2A receptors. Moreover, it possesses low affinity for 5-HT2C and H1 receptors (to reduce the risk of obesity associated with chronic treatment) and hERG channels (to reduce the incidence of torsade de pointes). In animal models, compound I inhibited apomorphine-induced climbing behavior, MK-801-induced hyperactivity, and the conditioned avoidance response without observable catalepsy at the highest dose tested. Further, fewer preclin. adverse events were noted with I compared with risperidone in assays that measured prolactin secretion and weight gain. Acceptable pharmacokinetic properties were also noted with I. Taken together, I may constitute a novel class of drugs for the treatment of schizophrenia. In the experiment, the researchers used many compounds, for example, Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8Recommanded Product: Ethyl 3-oxo-3-(thiophen-2-yl)propanoate).

Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8) 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. 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.Recommanded Product: Ethyl 3-oxo-3-(thiophen-2-yl)propanoate

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

Sun, Shaojing et al. published their research in Environmental Science and Pollution Research in 2021 | CAS: 84-61-7

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. 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.Application of 84-61-7

The spatiotemporal distribution and potential risk assessment of 19 phthalate acid esters in wastewater treatment plants in China was written by Sun, Shaojing;Shen, Jimin;Li, Bo;Geng, Jialu;Ma, Lixin;Qi, Hong;Zhang, Anping;Zhao, Zebin. And the article was included in Environmental Science and Pollution Research in 2021.Application of 84-61-7 This article mentions the following:

The spatiotemporal distribution of phthalate acid esters (phthalates, PAEs) in wastewater treatment plants (WWTPs) in China was studied. The concentration of PAEs in influent and effluent increased from 2009 to 2016, indicating that the exposure level of PAEs in China increased continuously. Although the concentration of PAEs in sewage sludge in China ranged from 33.3 to 298 ug/g, there was no obvious spatial distribution pattern. Among the 19 PAE homologues, DEHP, DnBP, and DIBP were the most abundant phthalates detected in wastewater and sludge. Ecol. risk assessment confirmed that there was a high chronic and acute risk of DIBP in effluent since 2015. Therefore, this study highlights the need for further studies on the exposure and toxicol. of DIBP. Dietary intake accounted for more than 98% of the total risk, indicating that the risk of sludge application in agricultural land was much higher than that in nonagricultural land. The results from this study will provide valuable information for the safe disposal of sludge and wastewater. 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. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. 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.Application of 84-61-7

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

Liu, Runzeng et al. published their research in Environmental Science & Technology Letters in 2021 | CAS: 6683-19-8

2,2-Bis(((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoyl)oxy)methyl)propane-1,3-diyl bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoate) (cas: 6683-19-8) 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. 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.HPLC of Formula: 6683-19-8

Single-Use Face Masks as a Potential Source of Synthetic Antioxidants to the Environment was written by Liu, Runzeng;Mabury, Scott A.. And the article was included in Environmental Science & Technology Letters in 2021.HPLC of Formula: 6683-19-8 This article mentions the following:

Single-use face masks are a powerful tool for reducing the spread of COVID-19. The usage of single-use face masks has increased enormously since the start of the COVID-19 pandemic, and pollution from the huge volume of discarded single-use face masks may become an environmental issue. This study focuses on synthetic antioxidants (AOs), including synthetic phenolic antioxidants (SPAs) and organophosphite antioxidants (OPAs), used in single-use 3-layer face masks. Both SPAs and OPAs were detected in single-use face masks, with total concentrations ranging 20.0-575μg/g (median of 175μg/g). The dominant congeners detected in the face masks were tris(2,4-di-tert-butylphenyl) phosphite (AO168, median of 83.2μg/g), tris(2,4-di-tert-butylphenyl) phosphate (AO168O, median of 72.9μg/g), and pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (AO1010, median of 13.7μg/g). No significant concentration difference was observed between medical and nonmedical face masks. Among the 3 different layers of the face masks, the middle layers showed the highest AO concentrations On the basis of the median concentrations detected, we estimate that 1084 tons of AOs is used in face masks annually, suggesting that discarded face masks may be a source of AOs to the environment. This is the 1st study to report the occurrence of a wide range of AOs in face masks. In the experiment, the researchers used many compounds, for example, 2,2-Bis(((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoyl)oxy)methyl)propane-1,3-diyl bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoate) (cas: 6683-19-8HPLC of Formula: 6683-19-8).

2,2-Bis(((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoyl)oxy)methyl)propane-1,3-diyl bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoate) (cas: 6683-19-8) 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. 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.HPLC of Formula: 6683-19-8

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

Welke, Juliane Elisa et al. published their research in Food Research International in 2014 | CAS: 106-79-6

Dimethyl decanedioate (cas: 106-79-6) 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. 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.Quality Control of Dimethyl decanedioate

Quantitative analysis of headspace volatile compounds using comprehensive two-dimensional gas chromatography and their contribution to the aroma of Chardonnay wine was written by Welke, Juliane Elisa;Zanus, Mauro;Lazzarotto, Marcelo;Alcaraz Zini, Claudia. And the article was included in Food Research International in 2014.Quality Control of Dimethyl decanedioate This article mentions the following:

The quant. determination of volatile compounds of Chardonnay wines using HS-SPME-GC × GC/TOFMS along with the determination of odor activity value (OAV) and relative odor contribution (ROC) of volatiles are reported for the first time. The use of GC × GC/TOFMS for the anal. of Chardonnay wine of Serra Gaucha resulted in the tentative identification of 243 compounds, showing the superior performance of this anal. technique for this specific varietal wine, considering that the number of compounds usually separated by 1D-GC for this type of wine is lower. Furthermore, 42 compounds co-eluted in the first dimension and 34 of them were separated in the second dimension, while the others were resolved by spectral deconvolution (8), which indicates that the conventional 1D-GC/MS may result in misleading results. The calculation of OAV and ROC allowed the determination of the volatile compounds that presented the greater contribution to wine aroma. Et octanoate, Et hexanoate, Et butanoate, and beta-damascenone showed the highest OAV and ROC values, although other 43 compounds showed also potential to contribute to wine aroma. Figures of merit of the developed method were: accuracies from 92.4 to 102.6%, repeatability from 1.2% to 13.4%, LOD from 0.001 μg L 1 (Et isovalerate and hexanoic acid) to 2.554 μg L 1 (Et 3-hydroxybutanoate), LOQ from 0.003 μg L 1 (Et isovalerate and hexanoic acid) to 7.582 μg L 1 (Et 3-hydroxybutanoate). In the experiment, the researchers used many compounds, for example, Dimethyl decanedioate (cas: 106-79-6Quality Control of Dimethyl decanedioate).

Dimethyl decanedioate (cas: 106-79-6) 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. 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.Quality Control of Dimethyl decanedioate

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

Liu, Dachun et al. published their research in Journal of Organic Chemistry in 2003 | CAS: 2199-49-7

Ethyl 4-methyl-1H-pyrrole-3-carboxylate (cas: 2199-49-7) 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. 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.Electric Literature of C8H11NO2

Conjugated Macrocycles Related to the Porphyrins. 25.Proton NMR Spectroscopic Evidence for a Preferred [18]Annulene Substructure in Carbaporphyrins from the Magnitude of Selected 4JH,H CH:C-CH3 Coupling Constants was written by Liu, Dachun;Lash, Timothy D.. And the article was included in Journal of Organic Chemistry in 2003.Electric Literature of C8H11NO2 This article mentions the following:

Two new benzocarbaporphyrins with four or five alkyl substituents have been synthesized by the “3 + 1” MacDonald methodol. At lower temperatures, the proton NMR spectrum of the asym. substituted carbaporphyrin I gave two NH resonances, while carbaporphyrin II, which retains a plane of symmetry, gave only one resonance of this kind. As no addnl. peaks were seen for the remaining protons, these data strongly support the proposal that a single tautomer predominates in solution where the two NH protons flank the interior CH. Carbaporphyrin I, which has a CH:CMe unit on the pyrrolic ring opposite the indene moiety, gave a long-range coupling constant of 4JMe,H = 1.3-1.4 Hz. On the other hand, the CH:CMe units of II, which correspond to the pyrrole rings on each side of the carbocyclic moiety, gave 4JMe,H = 0.9-1.0 Hz. These values are in accord with those expected if the exterior carbon-carbon bonds of the pyrrole units next to the indene ring are part of a fully delocalized 18π electron system, while the C:C bond of the remaining pyrrole ring retains substantial olefinic character. In the experiment, the researchers used many compounds, for example, Ethyl 4-methyl-1H-pyrrole-3-carboxylate (cas: 2199-49-7Electric Literature of C8H11NO2).

Ethyl 4-methyl-1H-pyrrole-3-carboxylate (cas: 2199-49-7) 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. 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.Electric Literature of C8H11NO2

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

Li, Yanni et al. published their research in Synthetic Communications in 2019 | CAS: 13669-10-8

Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8) 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. 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.Product Details of 13669-10-8

Copper-catalyzed cyanoisopropylation of beta-keto esters using azos: synthesis of beta-dicarbonyls bearing an alfa-tertiary nitrile moiety was written by Li, Yanni;Yang, Ruirong;Zhao, Xiaohui;Yao, Yongchao;Yang, Siping;Wu, Qiong;Liang, Deqiang. And the article was included in Synthetic Communications in 2019.Product Details of 13669-10-8 This article mentions the following:

A copper-catalyzed α-cyanoisopropylation reaction of β-keto esters using azo compounds as cyanoalkylating agents is presented, providing an easy access to β-dicarbonyls containing an α-tertiary nitrile moiety with adjacent tertiary and quaternary carbon centers. It is remarkable because a tremendous steric conflict is involved during reaction. Such nitriles were otherwise unavailable, and the reaction features simple and relatively mild conditions and good functional-group tolerance. In the experiment, the researchers used many compounds, for example, Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8Product Details of 13669-10-8).

Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8) 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. 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.Product Details of 13669-10-8

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