Journal articles: 'Chemical inhibitors'

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Osadchuk, T. V., O. V. Shybyryn, and V. K. Kibirev. "Chemical structure and properties of low-molecular furin inhibitors." Ukrainian Biochemical Journal 88, no. 6 (December 14, 2016): 5–25. http://dx.doi.org/10.15407/ubj88.06.005.

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Grant, Karen M., Morag H. Dunion, Vanessa Yardley, Alexios-Leandros Skaltsounis, Doris Marko, Gerhard Eisenbrand, Simon L. Croft, Laurent Meijer, and Jeremy C. Mottram. "Inhibitors of Leishmania mexicana CRK3 Cyclin-Dependent Kinase: Chemical Library Screen and Antileishmanial Activity." Antimicrobial Agents and Chemotherapy 48, no. 8 (August 2004): 3033–42. http://dx.doi.org/10.1128/aac.48.8.3033-3042.2004.

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ABSTRACT The CRK3 cyclin-dependent kinase of Leishmania has been shown by genetic manipulation of the parasite to be essential for proliferation. We present data which demonstrate that chemical inhibition of CRK3 impairs the parasite's viability within macrophages, thus further validating CRK3 as a potential drug target. A microtiter plate-based histone H1 kinase assay was developed to screen CRK3 against a chemical library enriched for protein kinase inhibitors. Twenty-seven potent CRK3 inhibitors were discovered and screened against Leishmania donovani amastigotes in vitro. Sixteen of the CRK3 inhibitors displayed antileishmanial activity, with a 50% effective dose (ED50) of less than 10 μM. These compounds fell into four chemical classes: the 2,6,9-trisubstituted purines, including the C-2-alkynylated purines; the indirubins; the paullones; and derivatives of the nonspecific kinase inhibitor staurosporine. The paullones and staurosporine derivatives were toxic to macrophages. The 2,6,9-trisubstituted purines inhibited CRK3 in vitro, with 50% inhibitory concentrations ranging from high nanomolar to low micromolar concentrations. The most potent inhibitors of CRK3 (compounds 98/516 and 97/344) belonged to the indirubin class; the 50% inhibitory concentrations for these inhibitors were 16 and 47 nM, respectively, and the ED50s for these inhibitors were 5.8 and 7.6 μM, respectively. In culture, the indirubins caused growth arrest, a change in DNA content, and aberrant cell types, all consistent with the intracellular inhibition of a cyclin-dependent kinase and disruption of cell cycle control. Thus, use of chemical inhibitors supports genetic studies to confirm CRK3 as a validated drug target in Leishmania and provides pharmacophores for further drug development.

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Kumar Dokka, Muni, Hemalatha K. P. J, and Siva Prasad Davuluri. "CHARACTERIZATION OF MONOHEADED TRYPSIN INHIBITORS FROM THE SEEDS OF ABELMOSCHUS MOSCHATUS L." Asian Journal of Pharmaceutical and Clinical Research 11, no. 12 (December 7, 2018): 459. http://dx.doi.org/10.22159/ajpcr.2018.v11i12.28735.

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Objective: The objective of the present study was to characterize the monoheaded trypsin inhibitors, Abelmoschus moschatus trypsin inhibitor-I (AMTI-I) and AMTI-II from the seeds of A. moschatus with respect to their specificity, mode of action, and active site residues.Methods: Standard methods were followed in determining inhibitory activities of monoheaded inhibitors. IC50 values and inhibitory constants (Ki) of AMTI-I and AMTI-II were determined. Studies on complex formation and chemical modification of inhibitors were performed.Results: AMTI-I and AMTI-II were found to be serpins, strongly active against trypsin, moderately active against porcine elastase, Staphylococcus aureus protease, and Aspergillus oryzae protease. AMTI-I and AMTI-II have shown non-competitive type of inhibition toward bovine trypsin with Ki values of inhibitors for trypsin found to be 0.25±0.02 nM and 0.22±0.06 nM, respectively. Complex studies revealed the formation of stable 1:1 complex of trypsin with both AMTI-I and AMTI-II. Chemical modification of the functional groups of the inhibitors by selective reagents indicated that arginine residues are essential for their trypsin inhibitory activities.Conclusion: Investigations on the specificity of protease inhibitors are important for understanding their physiological role, control mechanisms involved in the regulation of proteolysis in biological systems and mode of action.

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Li, Wenchao, Bowen Pan, Yang Shi, Meiying Wang, Tianjiao Han, Qing Wang, Guifang Duan, and Hongzheng Fu. "Identification of poly(ADP-ribose)polymerase 1 and 2 (PARP1/2) as targets of andrographolide using an integrated chemical biology approach." Chemical Communications 57, no. 51 (2021): 6308–11. http://dx.doi.org/10.1039/d1cc02272e.

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Andrographolide is the first PARP natural product inhibitor that does not contain an amide structure and has an inhibitory activity in the nanomolar range. This chemical structure is significant for expanding the structural type of PARP inhibitors.

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Sharma, Manish Kumar, Anil Kumar Sharma, and S. P. Mathur. "Solanum surrattence as Potential Corrosion Inhibitor." ISRN Corrosion 2012 (August 28, 2012): 1–5. http://dx.doi.org/10.5402/2012/907676.

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Developping chip and ecofriendlly corrosion inhibitors can replace toxic chemicals which are currently used in industries. Plant extract of Solanum surrattence in acetone, petroleum ether, and methanol has been tasted using mass loss and thermometric measurements for corrosion of aluminium in acid solutions. The plant extract of Solanum surrattence is a good corrosion inhibitor for aluminium. The inhibition efficiency depends upon the concentration of inhibitors, it inhibits the metal of 97.60% at its maximum value. This inhibitor shows efficiency at 25°C. At higher temperature the inhibition efficiency decreases. These types of inhibitors can be used to replace the toxic chemicals which are currently used in industries. We find out cheap and ecofriendlly corrosion inhibitors which can be used by acid, petrochemical, and chemical industries.

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Ernawati, Teni, Maksum Radji, Muhammad Hanafi, Abdul Mun’im, and Arry Yanuar. "Cinnamic Acid Derivatives as α-Glucosidase Inhibitor Agents." Indonesian Journal of Chemistry 17, no. 1 (April 1, 2017): 151. http://dx.doi.org/10.22146/ijc.23572.

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This paper reviews biological activity of some cinnamic acid derivative compounds which are isolated from natural materials and synthesized from the chemical compounds as an agent of α-glucosidase inhibitors for the antidiabetic drug. Aegeline, anhydroaegeline and aeglinoside B are natural products isolated compounds that have potential as an α-glucosidase inhibitor. Meanwhile, α-glucosidase inhibitor class of derivatives of cinnamic acid synthesized compounds are p-methoxy cinnamic acid and p-methoxyethyl cinnamate. Chemically, cinnamic acid has three main functional groups: first is the substitution of the phenyl group, second is the additive reaction into the α-β unsaturated, and third is the chemical reaction with carboxylic acid functional groups. The synthesis and modification of the structure of cinnamic acid are very influential in inhibitory activity against α-glucosidase.

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Juárez-Mercado, K. Eurídice, Fernando D. Prieto-Martínez, Norberto Sánchez-Cruz, Andrea Peña-Castillo, Diego Prada-Gracia, and José L. Medina-Franco. "Expanding the Structural Diversity of DNA Methyltransferase Inhibitors." Pharmaceuticals 14, no. 1 (December 27, 2020): 17. http://dx.doi.org/10.3390/ph14010017.

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Inhibitors of DNA methyltransferases (DNMTs) are attractive compounds for epigenetic drug discovery. They are also chemical tools to understand the biochemistry of epigenetic processes. Herein, we report five distinct inhibitors of DNMT1 characterized in enzymatic inhibition assays that did not show activity with DNMT3B. It was concluded that the dietary component theaflavin is an inhibitor of DNMT1. Two additional novel inhibitors of DNMT1 are the approved drugs glyburide and panobinostat. The DNMT1 enzymatic inhibitory activity of panobinostat, a known pan inhibitor of histone deacetylases, agrees with experimental reports of its ability to reduce DNMT1 activity in liver cancer cell lines. Molecular docking of the active compounds with DNMT1, and re-scoring with the recently developed extended connectivity interaction features approach, led to an excellent agreement between the experimental IC50 values and docking scores.

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Umezawa, Koji, and Isao Kii. "Druggable Transient Pockets in Protein Kinases." Molecules 26, no. 3 (January 27, 2021): 651. http://dx.doi.org/10.3390/molecules26030651.

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Drug discovery using small molecule inhibitors is reaching a stalemate due to low selectivity, adverse off-target effects and inevitable failures in clinical trials. Conventional chemical screening methods may miss potent small molecules because of their use of simple but outdated kits composed of recombinant enzyme proteins. Non-canonical inhibitors targeting a hidden pocket in a protein have received considerable research attention. Kii and colleagues identified an inhibitor targeting a transient pocket in the kinase DYRK1A during its folding process and termed it FINDY. FINDY exhibits a unique inhibitory profile; that is, FINDY does not inhibit the fully folded form of DYRK1A, indicating that the FINDY-binding pocket is hidden in the folded form. This intriguing pocket opens during the folding process and then closes upon completion of folding. In this review, we discuss previously established kinase inhibitors and their inhibitory mechanisms in comparison with FINDY. We also compare the inhibitory mechanisms with the growing concept of “cryptic inhibitor-binding sites.” These sites are buried on the inhibitor-unbound surface but become apparent when the inhibitor is bound. In addition, an alternative method based on cell-free protein synthesis of protein kinases may allow the discovery of small molecules that occupy these mysterious binding sites. Transitional folding intermediates would become alternative targets in drug discovery, enabling the efficient development of potent kinase inhibitors.

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Mohyaldinn, Mysara Eissa, Wai Lin, Ola Gawi, Mokhtar Che Ismail, Quosay A. Ahmed, Mohammed A. Ayoub, and Anas Hasan. "Experimental Investigation of a New Derived Oleochemical Corrosion Inhibitor." Key Engineering Materials 796 (March 2019): 112–20. http://dx.doi.org/10.4028/www.scientific.net/kem.796.112.

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Most of the corrosion inhibitors that are used in industry contain chemicals that are harmful to health and environment. Corrosion inhibitors derived from green sources are, therefore, believed to be a good option for replacing the chemical corrosion inhibitors. In this work, a green oleochemical corrosion inhibitor derived from Jatropha Curcas is introduced. The paper discusses the methodology of deriving the corrosion inhibitor as well as the experimental test conducted for evaluating its corrosion inhibition efficiency. The new oleochemical corrosion inhibitor was derived via two reactions. Jatropha oil was firstly saponified with sodium hydroxide to yield gras acid and glycerol, which was then esterified with boron fluoride in presence of excess methanol to produce the oil methyl esters, which is used as oleo-chemical corrosion inhibitor. To evaluate the oleo-chemical corrosion inhibitor, the corrosion rate of mild steel in NaCl corrosive medium with CO2 is tested at static condition and two dynamic conditions, namely 500 and 1500 rpm. This is to simulate the transitional and turbulent flow in a pipeline. At each dynamic condition, the proposed corrosion inhibitor was tested at concentration dosages of 0, 50, 100, and 150 ppm. The experiments results revealed a good performance of the new oleochemical corrosion inhibitor. The inhibition efficiency was found to be highly affected by the concentration of corrosion inhibitor. Total corrosion inhibition of the mild steel was noticed by using 150 ppm at dynamic condition of 500 rpm.

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Nasser, Rabab M., and Nora M. Masmali. "The effectiveness of Tamarindus Indica extracts as a metal corrosion inhibitor in various circumstances." Anti-Corrosion Methods and Materials 69, no. 3 (March 3, 2022): 224–33. http://dx.doi.org/10.1108/acmm-06-2021-2490.

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Purpose Plant development and use as green corrosion inhibitors are already recognized as one of the most environmentally friendly and effective protocols. In recent years, efforts have been made to find green corrosion inhibitors as an alternative to synthetic inhibitors for metals in acid medium. This paper aims to report the investigation of use of aqueous extracts of Tamarindus Indica as green inhibitors for corrosion of metals within different circumstances. Design/methodology/approach The use of Tamarindus Indica extracts (leaves, stem, fruit pulp and fruit husk) as corrosion inhibitors for mild steel and aluminum in different mediums (HCl, H2SO4, formic acid and citric acid) at different temperatures was investigated. Findings The inhibitory efficiency of Tamarindus Indica extracts increases with increasing concentration and decreases with increasing temperature. Langmuir is the adsorption isotherm, and the extract (inhibitor) is a mixed-type inhibitor (physisorption and chemisorption). Practical implications Tamarindus extracts (leaves, stem, fruit pulp and fruit husk) are effective inhibitors and can be used to protect metals from corrosion at different circumstances. Originality/value To the best of the authors’ knowledge, this is the first review that discusses the use of Tamarindus Indica extracts as corrosion inhibitors for metals.

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Chicca, Andrea, Simon Nicolussi, Ruben Bartholomäus, Martina Blunder, Alejandro Aparisi Rey, Vanessa Petrucci, Ines del Carmen Reynoso-Moreno, et al. "Chemical probes to potently and selectively inhibit endocannabinoid cellular reuptake." Proceedings of the National Academy of Sciences 114, no. 25 (June 5, 2017): E5006—E5015. http://dx.doi.org/10.1073/pnas.1704065114.

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The extracellular effects of the endocannabinoids anandamide and 2-arachidonoyl glycerol are terminated by enzymatic hydrolysis after crossing cellular membranes by facilitated diffusion. The lack of potent and selective inhibitors for endocannabinoid transport has prevented the molecular characterization of this process, thus hindering its biochemical investigation and pharmacological exploitation. Here, we report the design, chemical synthesis, and biological profiling of natural product-derivedN-substituted 2,4-dodecadienamides as a selective endocannabinoid uptake inhibitor. The highly potent (IC50= 10 nM) inhibitorN-(3,4-dimethoxyphenyl)ethyl amide (WOBE437) exerted pronounced cannabinoid receptor-dependent anxiolytic, antiinflammatory, and analgesic effects in mice by increasing endocannabinoid levels. A tailored WOBE437-derived diazirine-containing photoaffinity probe (RX-055) irreversibly blocked membrane transport of both endocannabinoids, providing mechanistic insights into this complex process. Moreover, RX-055 exerted site-specific anxiolytic effects on in situ photoactivation in the brain. This study describes suitable inhibitors to target endocannabinoid membrane trafficking and uncovers an alternative endocannabinoid pharmacology.

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Samsudin, Sity Juaeiriah, Nurlidia Binti Mansor, Suriati Sufian, and Zakaria B. Man. "The Potential of Garlic Extract as Bio-Inhibitor in Urea Fertilizer." Key Engineering Materials 594-595 (December 2013): 296–300. http://dx.doi.org/10.4028/www.scientific.net/kem.594-595.296.

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Urea is extensively used as fertilizer in the agricultural industry based on its suitability for all types of crops. The hydrolysis of urea fertilizer produces ammonia (NH3) and carbon dioxide (CO2). However, up to 40% of NH3 release affects the efficiency of urea fertilizer. By introducing inhibitors into the urea enzymatic reaction, the NH3 emission problem can be solved. Unfortunately, current inhibitors are usually chemical based and non-biodegradable. Several complaints and accidents have been reported when handling chemical based inhibitors especially for surface application. Research on garlic or Allium savatium has been conducted to ensure its inhibitory effects as potentially safe and biodegradable inhibitor. From previous research, thiosulfinates (TS) contained in garlic extract proved to inhibit platelets aggregation in medical applications. In this study, the inhibitory effect is determined by analyzing NH3 concentration in urease-garlic mixture and standard urea assay mixtures using UV-VIS spectrophotometer device. Previous research showed the highest absorbance of free NH3 was detected at 370nm. At 30 minutes of 15ml of urease-garlic mixture confirms the fully inhibition of garlic extract towards reaction.

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Leatherbarrow, Robin J., and Zulfiqar Hasan. "Introduction of trypsin specificity into chymotrypsin inhibitor ii." Protein & Peptide Letters 4, no. 5 (October 1997): 1. http://dx.doi.org/10.2174/092986650405221017154228.

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Abstract: A unique cysteine residue was introduced into the P1 pos1t1on of chymotrypsin inhibitor II (CI2) by - Jigonucleotide-directed mutagenesis (Met59 Cys). Chemical modification of CI2M59C with 2- bromoethylamine, 3-bromopropylamine and 2-mercaptoethylamine resulted in the introduction of lysine-sulfur analogues at the P1 position. Unlike the original CI2, all three modified inhibitors exhibited moderate but effective inhibition of trypsin. The results demonstrate that genetic and chemical modification can be successfully combined to tailor inhibitory specificity.

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Colquhoun, Jennifer M., Lisha Ha, Andrew Beckley, Brinkley Meyers, Daniel P. Flaherty, and Paul M. Dunman. "Identification of Small Molecule Inhibitors of Staphylococcus aureus RnpA." Antibiotics 8, no. 2 (April 28, 2019): 48. http://dx.doi.org/10.3390/antibiotics8020048.

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Staphylococcus aureus RnpA is thought to be a unique dual functional antimicrobial target that is required for two essential cellular processes, precursor tRNA processing and messenger RNA degradation. Herein, we used a previously described whole cell-based mupirocin synergy assay to screen members of a 53,000 compound small molecule diversity library and simultaneously enrich for agents with cellular RnpA inhibitory activity. A medicinal chemistry-based campaign was launched to generate a preliminary structure activity relationship and guide early optimization of two novel chemical classes of RnpA inhibitors identified, phenylcarbamoyl cyclic thiophene and piperidinecarboxamide. Representatives of each chemical class displayed potent anti-staphylococcal activity, limited the protein’s in vitro ptRNA processing and mRNA degradation activities, and exhibited favorable therapeutic indexes. The most potent piperidinecarboxamide RnpA inhibitor, JC2, displayed inhibition of cellular RnpA mRNA turnover, RnpA-depletion strain hypersusceptibility, and exhibited antimicrobial efficacy in a wax worm model of S. aureus infection. Taken together, these results establish that the whole cell screening assay used is amenable to identifying small molecule RnpA inhibitors within large chemical libraries and that the chemical classes identified here may represent progenitors of new classes of antimicrobials that target RnpA.

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Yildiz, Resit, and Basak Dogru Mert. "Theoretical and experimental investigations on corrosion control of mild steel in hydrochloric acid solution by 4-aminothiophenol." Anti-Corrosion Methods and Materials 66, no. 1 (January 7, 2019): 127–37. http://dx.doi.org/10.1108/acmm-04-2018-1920.

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Purpose This paper aims to study inhibitory effect of 4-aminothiophenol on the corrosion of mild steel (MS) in 0.5 M HCl. Design/methodology/approach In this study, electrochemical experiments, quantum chemical calculations, potentiodynamic measurements, linear polarization resistance and scanning electron microscopy were used. Findings The experimental results suggest that this compound is efficient corrosion inhibitor and the inhibition efficiencies increase with increasing their (from 0.5 to 10.0 mM.) concentrations. This reveals that inhibitive actions of inhibitors were mainly due to adsorption on mild steel surface. The adsorption of these inhibitors was found to obey Langmuir adsorption model. The computed quantum chemical features show good correlation with empirical inhibition efficiencies. Originality/value The 4-aminothiophenol is suitable inhibitor for application in closed-circuit systems against corrosion. The study is original and has great impact in industrial area. The obtained theoretical results have been adapted with the experimental data.

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Wu, Chuang Kun, Zong Wu Wei, Run Zhi Huang, Zhong Bao Yu, and Xiao Mu. "A Study of Several Inorganic Inhibitor Effected on Jamesonite and Marmatite Separation Flotation." Advanced Materials Research 616-618 (December 2012): 283–92. http://dx.doi.org/10.4028/www.scientific.net/amr.616-618.283.

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Study on the inorganic inhibitor on jamesonite and marmatite separation flotation，the result indicate the inhibition of minerals mainly has three forms. They are respectively: Inhibitor adsorbed on mineral surface to generate new chemical film which didn’t reaction with collector；After the adsorption of depressant, the reaction between depressant and the adsorbed collector molecule will occur on the mineral surface, which result in the ineffectiveness of the collector；Inhibitors and collector competitive to adsorb on mineral surface, and then the collector is pushed to the liquid phase.。The inhibitor’s performances are relevant to its oxidation and chemical property.

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Gao, Yinghong, Stephen P. Davies, Martin Augustin, Anna Woodward, Umesh A. Patel, Robert Kovelman, and Kevin J. Harvey. "A broad activity screen in support of a chemogenomic map for kinase signalling research and drug discovery." Biochemical Journal 451, no. 2 (March 28, 2013): 313–28. http://dx.doi.org/10.1042/bj20121418.

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Despite the development of a number of efficacious kinase inhibitors, the strategies for rational design of these compounds have been limited by target promiscuity. In an effort to better understand the nature of kinase inhibition across the kinome, especially as it relates to off-target effects, we screened a well-defined collection of kinase inhibitors using biochemical assays for inhibitory activity against 234 active human kinases and kinase complexes, representing all branches of the kinome tree. For our study we employed 158 small molecules initially identified in the literature as potent and specific inhibitors of kinases important as therapeutic targets and/or signal transduction regulators. Hierarchical clustering of these benchmark kinase inhibitors on the basis of their kinome activity profiles illustrates how they relate to chemical structure similarities and provides new insights into inhibitor specificity and potential applications for probing new targets. Using this broad dataset, we provide a framework for assessing polypharmacology. We not only discover likely off-target inhibitor activities and recommend specific inhibitors for existing targets, but also identify potential new uses for known small molecules.

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Liu, Yuan, and Ping Zhang. "Review of Phosphorus-Based Polymers for Mineral Scale and Corrosion Control in Oilfield." Polymers 14, no. 13 (June 30, 2022): 2673. http://dx.doi.org/10.3390/polym14132673.

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Production chemistry is an important field in the petroleum industry to study the physicochemical changes in the production system and associated impact on production fluid flow from reservoir to topsides facilities. Mineral scale deposition and metal corrosion are among the top three water-related production chemistry threats in the petroleum industry, particularly for offshore deepwater and shale operations. Mineral scale deposition is mainly driven by local supersaturation due to operational condition change and/or mixing of incompatible waters. Corrosion, in contrast, is an electrochemical oxidation–reduction process with local cathodic and anodic reactions taking place on metal surfaces. Both mineral scaling and metal corrosion can lead to severe operational risk and financial loss. The most common engineering solution for oilfield scale and corrosion control is to deploy chemical inhibitors, including scale inhibitors and corrosion inhibitors. In the past few decades, various chemical inhibitors have been prepared and applied for scaling and corrosion control. Phosphorus-based polymers are an important class of chemical inhibitors commonly adopted in oilfield operations. Due to the versatile molecular structures of these chemicals, phosphorus-based polymeric inhibitors have the advantage of a higher calcium tolerance, a higher thermal stability, and a wider pH tolerance range compared with other types of inhibitors. However, there are limited review articles to cover these polymeric chemicals for oilfield scale and corrosion control. To address this gap, this review article systematically reviews the synthesis, laboratory testing, and field applications of various phosphorus-based polymeric inhibitors in the oil and gas industry. Future research directions in terms of optimizing inhibitor design are also discussed. The objective is to keep the readers abreast of the latest development in the synthesis and application of these materials and to bridge chemistry knowledge with oilfield scale and corrosion control practice.

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Sõrmus, Tanel, Darja Lavogina, Erki Enkvist, Asko Uri, and Kaido Viht. "Deactivatable Bisubstrate Inhibitors of Protein Kinases." Molecules 27, no. 19 (October 8, 2022): 6689. http://dx.doi.org/10.3390/molecules27196689.

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Bivalent ligands, including bisubstrate inhibitors, are conjugates of pharmacophores, which simultaneously target two binding sites of the biomolecule. Such structures offer attainable means for the development of compounds whose ability to bind to the biological target could be modulated by an external trigger. In the present work, two deactivatable bisubstrate inhibitors of basophilic protein kinases (PKs) were constructed by conjugating the pharmacophores via linkers that could be cleaved in response to external stimuli. The inhibitor ARC-2121 incorporated a photocleavable nitrodibenzofuran-comprising β-amino acid residue in the structure of the linker. The pharmacophores of the other deactivatable inhibitor ARC-2194 were conjugated via reduction-cleavable disulfide bond. The disassembly of the inhibitors was monitored by HPLC-MS. The affinity and inhibitory potency of the inhibitors toward cAMP-dependent PK (PKAcα) were established by an equilibrium competitive displacement assay and enzyme activity assay, respectively. The deactivatable inhibitors possessed remarkably high 1–2-picomolar affinity toward PKAcα. Irradiation of ARC-2121 with 365 nm UV radiation led to reaction products possessing a 30-fold reduced affinity. The chemical reduction of ARC-2194 resulted in the decrease of affinity of over four orders of magnitude. The deactivatable inhibitors of PKs are valuable tools for the temporal inhibition or capture of these pharmacologically important enzymes.

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Sjulander, Nikki, and Timo Kikas. "Origin, Impact and Control of Lignocellulosic Inhibitors in Bioethanol Production—A Review." Energies 13, no. 18 (September 11, 2020): 4751. http://dx.doi.org/10.3390/en13184751.

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Bioethanol production from lignocellulosic biomass is still struggling with many obstacles. One of them is lignocellulosic inhibitors. The aim of this review is to discuss the most known inhibitors. Additionally, the review addresses different detoxification methods to degrade or to remove inhibitors from lignocellulosic hydrolysates. Inhibitors are formed during the pretreatment of biomass. They derive from the structural polymers-cellulose, hemicellulose and lignin. The formation of inhibitors depends on the pretreatment conditions. Inhibitors can have a negative influence on both the enzymatic hydrolysis and fermentation of lignocellulosic hydrolysates. The inhibition mechanisms can be, for example, deactivation of enzymes or impairment of vital cell structures. The toxicity of each inhibitor depends on its chemical and physical properties. To decrease the negative effects of inhibitors, different detoxification methods have been researched. Those methods focus on the chemical modification of inhibitors into less toxic forms or on the separation of inhibitors from lignocellulosic hydrolysates. Each detoxification method has its limitations on the removal of certain inhibitors. To choose a suitable detoxification method, a deep molecular understanding of the inhibition mechanism and the inhibitor formation is necessary.

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Gohil, Chirag J., Malleshappa N. Noolvi, Chhaganbhai N. Patel, and Dhrubo Jyoti Sen. "Chemical classification of MDM2 inhibitors." International Journal of Pharmaceutical Chemistry and Analysis 8, no. 2 (July 15, 2021): 41–44. http://dx.doi.org/10.18231/j.ijpca.2021.009.

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MDM2 inhibitors class of anti-neoplastic drugs has been evolve after the successful discovery of the nutlins and other potent inhibitors. MDM2 inhibitors can specifically target the tumour cells in the body, by selectively reactivating the inhibited p53 function in the tumour cells.None of the compound of this class has been entered into the market till date, all are under clinical trials. Hence, various researcher classifies them according to their p53 topology mimetic property and as per their peptide type or non-peptide type.Synthetic peptide type of inhibitors can mimic the conformation of p53 helix. Whereas, small organic molecule (non-peptide) type of MDM2 inhibitors have been further subdivided as Non α-helix mimetics (small molecule inhibitors) and α-helix mimetics. In a line with synthetic inhibitors, many potent MDM2 inhibitors are derived from the natural origin (marine, fungus). Therefore, keeping in a view of all these characteristics, here we have classified them as per best of our knowledge.

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Zharmukhamedov, S. K., and S. I. Allakhverdiev. "Chemical Inhibitors of Photosystem II." Russian Journal of Plant Physiology 68, no. 2 (March 2021): 212–27. http://dx.doi.org/10.1134/s1021443721020229.

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Schmitt, G. "‘Chemical inhibitors for corrosion control’." British Corrosion Journal 27, no. 1 (January 1992): 24–25. http://dx.doi.org/10.1179/000705992798268837.

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Albers, Harald M. H. G., and Huib Ovaa. "Chemical Evolution of Autotaxin Inhibitors." Chemical Reviews 112, no. 5 (February 15, 2012): 2593–603. http://dx.doi.org/10.1021/cr2003213.

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Bridges, Alexander J. "Chemical Inhibitors of Protein Kinases." Chemical Reviews 101, no. 8 (August 2001): 2541–72. http://dx.doi.org/10.1021/cr000250y.

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Abu, R. N., L. G. Amah, A. Dulu, and Olalekan Michael Adeloye. "Chemical Control of Natural Gas Hydrate." European Journal of Engineering and Technology Research 1, no. 6 (July 27, 2018): 58–62. http://dx.doi.org/10.24018/ejeng.2016.1.6.231.

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The study investigates chemical control of hydrates in pipeline by the application of different chemical substances such as methanol, ethylene glycol, diethylene glycol and triethylene glycol. Aspen Hysys simulator was used to determine hydrate formation temperature based on gas field composition and operating pressure by using Peng-Robinson equation. Similar simulations were carried out with the injection of chemical inhibitors such as methanol, ethylene glycol, diethylne glycol and triethylene glycol. The chemical inhibitors prevents hydrate formation by reducing hydrate formation temperature, thereby mitigating against hydrate formation and ensuring constant flow and production of fluid with methanol been the most effective chemical inhibitor based on the hydrate formation temperature reduction trends and analysis.

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Saefuloh, Iman, Nufus Kanani, Yazid Rukmayadi, Yusvardi Yusuf, Mahmud Barizya, and Syarif Abdullah. "The Corrosion Inhibition of API 5L Steel Using Natrium Acetate and Natrium Nitrite in Natrium Chloride Acid Solution." Materials Science Forum 988 (April 2020): 3–10. http://dx.doi.org/10.4028/www.scientific.net/msf.988.3.

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Using inhibitors becomes an alternative way to reduce the level of corrosion. One type of the inhibitors proven effective is inorganic or chemical inhibitors. Regarding this, the purpose of this study is to determine the effectiveness of chemical inhibitors in reducing the level of corrosion. This study showed that the addition of natrium acetate and natrium was proven effective in reducing the corrosion, with the level of inhibitor efficiency of 75%. The result also showed that the inhibitors gave good performance to inhibit corrosion attack in natrium chloride acid medium, the form of corrosion that occurs in API 5L material is uniform corrosion.

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Andrianov, Alexey, and Zhanna Govorova. "Study of various organophosphonate additives as calcium carbonate inhibitors for reverse osmosis." E3S Web of Conferences 100 (2019): 00001. http://dx.doi.org/10.1051/e3sconf/201910000001.

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Various chemical additives are used in water treatment industry, among them – precipitation inhibitors for reverse osmosis membrane facilities. The development and synthesis of new inhibitor formulas and the study of their effectiveness is still an urgent task for many researchers working in this field. The relationship between the structure of phosphonate scale inhibitors and their effectiveness in preventing of calcium carbonate precipitation was studied. Two classes of tetraphosphonate and diphosphonate inhibitors that possess systematic structural similarities and differences have been tested on the laboratory membrane unit. All chemicals were tested at doses of 1 and 5 mg/L. The results showed that the antiscalant efficiency for both groups of inhibitors increases with elongation of methylene chain, but the longest compounds have a sharp drop in inhibition efficiency.

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Xie, Jianli, Jiayuan Hu, Jundong Lu, and Xinmin Li. "Inhibiters replacement of chilled water system in nuclear unit." Anti-Corrosion Methods and Materials 64, no. 4 (June 5, 2017): 418–23. http://dx.doi.org/10.1108/acmm-02-2016-1647.

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Purpose The purpose of this paper was to study the corrosion control of B10 copper-nickel alloy using the LiOH-N2H4 compound inhibitors and to evaluate the feasibility of replacing the original inhibitors (NaNO2-Na2MoO4) with the new ones (LiOH-N2H4) for the chilled water system in a nuclear unit. Design/methodology/approach The corrosion resistance performance of B10 copper-nickel alloy was evaluated during the whole replacement process of inhibiters using electrochemical tests and surface analysis techniques. Findings The results indicated that the corrosion of B10 copper-nickel alloy could be prevented effectively using LiOH to increase the pH value of solution higher than 10.0 and using N2H4 to consume dissolved oxygen. During the replacement process of inhibitors from NaNO2-Na2MoO4 to LiOH-N2H4, the corrosion resistance performance of B10 copper-nickel alloy had not decreased greatly. The new LiOH-N2H4 inhibitor, which could enhance the compactness of rust, was able to reduce the corrosion rate of rusted B10 metal. Originality/value It is feasible and operable to replace the NaNO2-Na2MoO4 inhibitors with the LiOH-N2H4 inhibitors for the corrosion prevention of B10 copper-nickel alloy. The research results can provide guidelines for the inhibitor selection of chilled water system in a nuclear unit.

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Temkitthawon, Prapapan, Kanokwan Changwichit, Nantaka Khorana, Jarupa Viyoch, Khanit Suwanborirux, and Kornkanok Ingkaninan. "Phenanthrenes from Eulophia macrobulbon as Novel Phosphodiesterase-5 Inhibitors." Natural Product Communications 12, no. 1 (January 2017): 1934578X1701200. http://dx.doi.org/10.1177/1934578x1701200121.

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Phosphodiesterase 5 (PDE5) inhibitors can be used for the treatment of erectile dysfunction and pulmonary hypertension. In order to search for new leads of PDE5 inhibitors, we investigated the chemical constituents of the tubers of Eulophia macrobulbon (E.C. Parish & Rchb. f) Hook. f A new phenanthrene, 9,10-dihydro-4-(4′-hydroxybenzyl)-2,5-dimethoxyphenanthrene-1,7-diol (1) and three known phenanthrenes i.e., 1-(4′-hydroxybenzyl)-4,8-dimethoxyphenanthrene-2,7-diol (2), (9,10-dihydro-2,5-dimethoxyphenanthrene-1,7-diol (3) and 1,5,7-trimethoxyphenanthrene-2,6-diol) (4) were isolated. Among these, 2 was the most potent PDE5 inhibitor (IC50 =1.67±0.54 μM) evaluated by the [3H]cGMP radioassay method, whereas 1 showed mild activity (IC50 = 62.3±3.3 μM). Their inhibitory selectivities against PDE5 over PDE6 were also studied. This study suggests phenanthrenes as a new class of PDE5 inhibitors.

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Tsuda, Yuko, Koushi Hidaka, Keiko Hojo, and Yoshio Okada. "Exploration of Active Site-Directed Plasmin Inhibitors: Beyond Tranexamic Acid." Processes 9, no. 2 (February 11, 2021): 329. http://dx.doi.org/10.3390/pr9020329.

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Plasmin (Plm), a trypsin-like serine protease, is responsible for fibrinolysis pathway and pathologic events, such as angiogenesis, tumor invasion, and metastasis, and alters the expression of cytokines. A growing body of data indicates that a Plm inhibitor is a potential candidate as an anti-inflammatory and anti-cancer agent. A class of active site-directed plasmin inhibitors containing tranexamic acid residue has been designed. As evidenced by docking studies, the inhibitor binds to the active site not to the lysine binding site (LBS) in plasmin, thus preventing plasmin from digesting the substrate. Further optimization of the series, concerning both activity and selectivity, led to the second generation of inhibitors. This review focuses on the Plm inhibitory activity-structure relationship of Plm inhibitors with the goal of realizing their design and clinical application.

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Basagiannis, Dimitris, Sofia Zografou, Evangeli Goula, Despoina Gkeka, Evangelos Kolettas, and Savvas Christoforidis. "Chemical Inhibitors of Dynamin Exert Differential Effects in VEGF Signaling." Cells 10, no. 5 (April 23, 2021): 997. http://dx.doi.org/10.3390/cells10050997.

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VEGFR2 is the main receptor and mediator of the vasculogenic and angiogenic activity of VEGF. Activated VEGFR2 internalizes through clathrin-mediated endocytosis and macropinocytosis. As dynamin is a key regulator of the clathrin pathway, chemical inhibitors of dynamin are commonly used to assess the role of the clathrin route in receptor signaling. However, drugs may also exert off-target effects. Here, we compare the effects of three dynamin inhibitors, dynasore, dyngo 4a and dynole, on VEGFR2 internalization and signaling. Although these drugs consistently inhibit clathrin-mediated endocytosis of both transferrin (a typical cargo of this route) and VEGFR2, surprisingly, they exert contradictory effects in receptor signaling. Thus, while dynasore has no effect on phosphorylation of VEGFR2, the other two drugs are strong inhibitors. Furthermore, although dyngo does not interfere with phosphorylation of Akt, dynasore and dynole have a strong inhibitory effect. These inconsistent effects suggest that the above dynamin blockers, besides inhibiting dynamin-dependent endocytosis of VEGFR2, exert additional inhibitory effects on signaling that are independent of endocytosis; i.e., they are due to off-target effects. Using a recently developed protocol, we comparatively validate the specificity of two endocytic inhibitors, dynasore and EIPA. Our findings highlight the importance of assessing whether the effect of an endocytic drug on signaling is specifically due to its interference with endocytosis or due to off-targets.

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Ahmadbaygi, Afshar, Behrouz Bayati, Mohsen Mansouri, Hossein Rezaei, and Masoud Riazi. "Chemical study of asphaltene inhibitors effects on asphaltene precipitation of an Iranian oil field." Oil & Gas Science and Technology – Revue d’IFP Energies nouvelles 75 (2020): 6. http://dx.doi.org/10.2516/ogst/2019063.

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The amount of precipitated asphaltene can be considerably reduced with pretreatment of asphaltene inhibitor, in the crude oil. Efficiency of asphaltene inhibitors mainly depends on some parameters such as pH of the oil and the chemical structure of asphaltene inhibitors. In this paper, the amounts of asphaltene precipitation have been experimentally measured using two n-paraffin precipitants; n-heptane and n-hexane. The performance of the studies on the asphaltene accumulation was studied using Fourier-Transform Infrared (FTIR) Spectroscopy analysis. The onset point has been determined by three different commercial asphaltene inhibitors. The results show that when an asphaltene inhibitor is not injected into the mixture of synthetic oil/n-heptane, AOP (Asphaltene Onset Point) occurs at 35 vol.% of n-heptane, while with addition of 3000 ppm of asphaltene B inhibitor, AOP occurs at 60 vol.% of n-heptane.

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Cheng, Zishuo, Caitlyn A. Thomas, Adam R. Joyner, Robert L. Kimble, Aidan M. Sturgill, Nhu-Y. Tran, Maya R. Vulcan, et al. "MBLinhibitors.com, a Website Resource Offering Information and Expertise for the Continued Development of Metallo-β-Lactamase Inhibitors." Biomolecules 10, no. 3 (March 16, 2020): 459. http://dx.doi.org/10.3390/biom10030459.

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In an effort to facilitate the discovery of new, improved inhibitors of the metallo-β-lactamases (MBLs), a new, interactive website called MBLinhibitors.com was developed. Despite considerable efforts from the science community, there are no clinical inhibitors of the MBLs, which are now produced by human pathogens. The website, MBLinhibitors.com, contains a searchable database of known MBL inhibitors, and inhibitors can be searched by chemical name, chemical formula, chemical structure, Simplified Molecular-Input Line-Entry System (SMILES) format, and by the MBL on which studies were conducted. The site will also highlight a “MBL Inhibitor of the Month”, and researchers are invited to submit compounds for this feature. Importantly, MBLinhibitors.com was designed to encourage collaboration, and researchers are invited to submit their new compounds, using the “Submit” function on the site, as well as their expertise using the “Collaboration” function. The intention is for this site to be interactive, and the site will be improved in the future as researchers use the site and suggest improvements. It is hoped that MBLinhibitors.com will serve as the one-stop site for any important information on MBL inhibitors and will aid in the discovery of a clinically useful MBL inhibitor.

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Yuan, Wei, Xin-Yun Zhao, Xi Chen, and Chang-Guo Zhan. "Purin-6-One Derivatives as Phosphodiesterase-2 Inhibitors." Journal of Chemistry 2016 (2016): 1–10. http://dx.doi.org/10.1155/2016/6878353.

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A series of purin-6-one derivatives were synthesized, and theirin vitroinhibitory activity against phosphodiesterase-2 (PDE2) was evaluated by using a fluorescence polarization assay. Three compounds, that are,2j,2p, and2q, showed significant inhibitory activity against PDE2 with IC50values of 1.73, 0.18, and 3.43 μM, respectively. Structure-activity relationship (SAR) analysis was performed to explore the relationship between the chemical structures of these compounds and their inhibitory activity. Compounds2j,2p, and2qwere further selected for molecular docking study. The docking results suggested that these ligands bind with hydrophobic pockets of the catalytic active site of PDE2, where a Tyr655 residue was found to be important in binding with compound2p, the most potent inhibitor identified in this study. Our present study provides useful information for the future design of novel PDE2 inhibitors.

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Kurland, Andrew P., Boris Bonaventure, and Jeffrey R. Johnson. "A Chemical Proteomics Approach to Discover Regulators of Innate Immune Signaling." Viruses 15, no. 5 (May 3, 2023): 1112. http://dx.doi.org/10.3390/v15051112.

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Innate immune pathways are tightly regulated to balance an appropriate response to infectious agents and tolerable levels of inflammation. Dysregulation of innate immune pathways can lead to severe autoinflammatory disorders or susceptibility to infections. Here, we aimed to identify kinases in common cellular pathways that regulate innate immune pathways by combining small-scale kinase inhibitor screening with quantitative proteomics. We found that inhibitors of kinases ATM, ATR, AMPK, and PLK1 reduced the induction of interferon-stimulated gene expression in response to innate immune pathway activation by poly(I:C) transfection. However, siRNA depletion of these kinases did not validate findings with kinase inhibitors, suggesting that off-target effects may explain their activities. We mapped the effects of kinase inhibitors to various stages in innate immune pathways. Determining the mechanisms by which kinase inhibitors antagonize these pathways may illuminate novel mechanisms of innate immune pathway control.

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Habash, Maha, Sami Alshakhshir, Shady Awwad, and Mahmoud Abu-Samak. "The discovery of potential tumor necrosis factor alpha converting enzyme inhibitors via implementation of K Nearest Neighbor QSAR analysis." Pharmacia 70, no. 2 (April 12, 2023): 247–61. http://dx.doi.org/10.3897/pharmacia.70.e96423.

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Tumor necrosis factor-alpha converting enzyme (TACE) is considered as a pro-inflammatory cytokine which catalyzes the formation of TNF-α from membrane bound TNF-α precursor protein. It has important role in various pathological diseases such as inflammation, anorexia, rheumatoid arthritis, cancer and viral replication. Despite the reporting of a variety of TACE inhibitors of diverse chemical scaffolds whether peptide, peptide-like compounds or others, the bioavailability and pharmacokinetic problems are reflected strongly on its clinical effectiveness. In this effort we employed a novel combination of k-nearest neighbor QSAR modeling to select the best critical ligand-TACE contacts capable of elucidation of TACE inhibitory bioactivity among a long list of inhibitors. The recurrence of one valid pharmacophore hypothesis among the successful models emerged the pharmacophore to be used as 3D search queries to screen the National Cancer Institute’s structural database for new TACE inhibitors. Eight potent TACE inhibitors were discovered with inhibition percentage exceeding 50% at 100 μM inhibitor concentration.

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Cheban, S. E., M. D. Valeev, S. A. Leontiev, and A. F. Semenenko. "Technical solution for supplying a wax (deposition) inhibitor to a tubing string of oil wells." Oil and Gas Studies, no. 2 (June 2, 2020): 82–88. http://dx.doi.org/10.31660/0445-0108-2020-2-82-88.

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For prevention and combating paraffin deposites different chemical regents are widely used (wax inhibitors). In field conditions many ways of chemical regents dosing are applied. Injection of chemical reagents in oil well tubing is the most effective for wax inhibitors; in this case consumption of reagents is largely decreasing by comparison with chemical reagents dosing through the well-casing annulus. The article describes design and operating processes of technology of wax inhibitor dosing in electric centrifugal well pumps installation. This process opens fluid access to oil well tubing at higher pressure at the wellhead. Reagent RT-1-3 is used as aromatic wax inhibitor. In RT-1-3 there is butylbenzene fraction of Kazanorgsintez PJSC containing a mixture of butylbenzene, isopropylbenzene and polyalkylbenzene.

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Kapoor, Khyati, Janet S. Finer-Moore, Bjørn P. Pedersen, Laura Caboni, Andrew Waight, Roman C. Hillig, Peter Bringmann, et al. "Mechanism of inhibition of human glucose transporter GLUT1 is conserved between cytochalasin B and phenylalanine amides." Proceedings of the National Academy of Sciences 113, no. 17 (April 12, 2016): 4711–16. http://dx.doi.org/10.1073/pnas.1603735113.

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Cancerous cells have an acutely increased demand for energy, leading to increased levels of human glucose transporter 1 (hGLUT1). This up-regulation suggests hGLUT1 as a target for therapeutic inhibitors addressing a multitude of cancer types. Here, we present three inhibitor-bound, inward-open structures of WT-hGLUT1 crystallized with three different inhibitors: cytochalasin B, a nine-membered bicyclic ring fused to a 14-membered macrocycle, which has been described extensively in the literature of hGLUTs, and two previously undescribed Phe amide-derived inhibitors. Despite very different chemical backbones, all three compounds bind in the central cavity of the inward-open state of hGLUT1, and all binding sites overlap the glucose-binding site. The inhibitory action of the compounds was determined for hGLUT family members, hGLUT1–4, using cell-based assays, and compared with homology models for these hGLUT members. This comparison uncovered a probable basis for the observed differences in inhibition between family members. We pinpoint regions of the hGLUT proteins that can be targeted to achieve isoform selectivity, and show that these same regions are used for inhibitors with very distinct structural backbones. The inhibitor cocomplex structures of hGLUT1 provide an important structural insight for the design of more selective inhibitors for hGLUTs and hGLUT1 in particular.

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Kalyn, Tetyana, Liubomyr Poberezhny, and Dmytro Melnyk. "Experimental and quantum chemical studies of some derivative of decahydroacridinedione-1,8 as corrosion inhibitor of steel 17 gs in ns4 solution." Scientific journal of the Ternopil national technical university 1, no. 101 (2021): 129–37. http://dx.doi.org/10.33108/visnyk_tntu2021.01.129.

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The use of inhibitors remains one of the most effective and economically sound methods of corrosion protection in various aggressive environments. Since universal inhibitors do not exist, effective inhibitors or compositions should be developed for each individual case. The inhibitory properties of N – phenyl – decahydroacridindiones – 1,8 in groundwater imitats were investigated in this research. Inhibitory properties has been studied by the use of the electrochemical and gravimetric methods.

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Elhenawy, Salma, Majeda Khraisheh, Fares Almomani, Mohammad Al-Ghouti, Mohammad Hassan, and Ala’a Al-Muhtaseb. "Towards Gas Hydrate-Free Pipelines: A Comprehensive Review of Gas Hydrate Inhibition Techniques." Energies 15, no. 22 (November 15, 2022): 8551. http://dx.doi.org/10.3390/en15228551.

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Gas hydrate blockage is a major issue that the production and transportation processes in the oil/gas industry faces. The formation of gas hydrates in pipelines results in significant financial losses and serious safety risks. To tackle the flow assurance issues caused by gas hydrate formation in the pipelines, some physical methods and chemical inhibitors are applied by the oil/gas industry. The physical techniques involve subjecting the gas hydrates to thermal heating and depressurization. The alternative method, on the other hand, relies on injecting chemical inhibitors into the pipelines, which affects gas hydrate formation. Chemical inhibitors are classified into high dosage hydrate inhibitors (thermodynamic hydrate inhibitors (THI)) and low dosage hydrate inhibitors (kinetic hydrate inhibitors (KHI) and anti-agglomerates (AAs)). Each chemical inhibitor affects the gas hydrate from a different perspective. The use of physical techniques (thermal heating and depressurization) to inhibit hydrate formation is studied briefly in this review paper. Furthermore, the application of various THIs (alcohols and electrolytes), KHIs (polymeric compounds), and dual function hydrate inhibitors (amino acids, ionic liquids, and nanoparticles) are discussed thoroughly in this study. This review paper aims to provide a complete and comprehensive outlook on the fundamental principles of gas hydrates, and the recent mitigation techniques used by the oil/gas industry to tackle the gas hydrate formation issue. It hopes to provide the chemical engineering platform with ultimate and effective techniques for gas hydrate inhibition.

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Flaumenhaft, Robert, Lynn VerPlank, James R. Dilks, Price S. Blair, Albert Mairuhu, Joseph Negri, Jason Burbank, et al. "A Chemical Genetic Analysis of Platelet Activation." Blood 114, no. 22 (November 20, 2009): 4009. http://dx.doi.org/10.1182/blood.v114.22.4009.4009.

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Abstract Abstract 4009 Poster Board III-945 Platelets are anucleate cells that are not amenable to traditional forward genetic analysis. In collaboration with the Broad Institute Probe Development Center, we have performed a chemical genetic analysis of platelet activation. Chemical genetics involves exposure of cells to a library of small molecules, identification of compounds that produce a phenotype of interest, and determination of the target of these small molecules. We have used an assay designed both to identify allosteric inhibitors of Protease Activated Receptor-1 (PAR1) and to find inhibitors that selectively target granule release. This assay monitors dense granule secretion mediated by SFLLRN, a PAR1-specific agonist, using a luciferase-based assay system to detect ADP/ATP release. For primary screening, over 300,000 compounds were assayed in duplicate using freshly outdated platelet-rich plasma supplied by several blood banks across the United States. Computational analyses of the primary data demonstrated that approximately 0.2% of compounds showed ≥50% inhibition relative to maximally inhibitory concentrations of the known antiplatelet agent, cilostazol. Secondary screening using 8-point dose response curves were performed on the 629 inhibitory compounds, 742 compounds with inconclusive activity (e.g., ambiguous duplicates in primary screening), and 213 structural analogs of active compounds. These assays identified 367 active compounds with IC50s ≤10 micromolar. Counter screening to exclude luciferase inhibitors demonstrated 137 small molecules that inhibited PAR1-mediated ATP/ADP release without significant inhibition of luciferase. Database mining using PubChem and CAS search engines was performed to assess the selectivity of active compounds. Twenty eight compounds were selected for further testing based on their IC50s in confirmatory assays, lack of activity in unrelated bioassays, and chemical structure. Known platelet inhibitors were excluded. Of the 28 compounds, 16 compounds potently inhibited SFLLRN-induced alpha-granule release from washed platelets, as monitored by P-selectin expression. IC50s for these compounds ranged from <0.3 to 1 micromolar. None of the selected compounds that failed to inhibit alpha-granule release demonstrated significant inhibition of SFLLRN-induced 14C-serotonin release at 10 micromolar. Ongoing studies are directed at selecting best candidates from among the 16 confirmed inhibitory compounds to develop as biological probes that target either PAR1 activation or distal steps in granule secretion. Disclosures: No relevant conflicts of interest to declare.

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Kassenova, Zh. "Residual chemical analysis of amines used as corrosion inhibitors." Bulletin of the Innovative University of Eurasia 80, no. 4 (December 25, 2020): 109–14. http://dx.doi.org/10.37788/2020-4/109-114.

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Main problem: Presence of acidic chemicals such as carbon dioxide and hydrogen sulphide, composition of production fluids triggers corrosion. Corrosion in oil and gas industry leads to deterioration of equipment since most of equipment is made of metal alloys. Application of inhibitors is one of the corrosion mitigation methods that needs to be controlled because it is important to identify optimal concentration of the chemicals in production fluids.Residual chemical analysis plays an important rolein identifying the appropriate dosage of corrosion inhibitors and its correction. It is imperative to find the most optimal concentration of amines due to the fact that both overdose and underdose could lead to equipment deterioration. The chemical analysis is hindered by complexity of mixtures that are applied in petroleum industry. Purpose: The main purpose of this article is to find out the most effective method of residual chemical analysis for inhibitors used against sweet and sour corrosion by studying and analyzing corresponding literature review. The analysis should be carried out with robust, sensitive, and accurate instrumentation. Methods :Theoretical study of composition and mechanism of amines used in oil and gas industry as corrosion inhibitors and selection of appropriate instrumental analytical techniques for the residual analysis. Results and their importance: After careful studying and consideration of modern instrumental analytical techniques the most optimal and efficient method in terms of robustness, time saving and cost was selected. Ion chromatography is an adequate method to carry out residual chemical analysis for amines that are used as inhibitors in oil and gas industry to prevent sweet and sour corrosion.

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Purish, L. M., D. R. Abdulina, and G. O. Iutynska. "Inhibitors of Corrosion Induced by Sulfate-Reducing Bacteria." Mikrobiolohichnyi Zhurnal 83, no. 6 (December 17, 2021): 95–109. http://dx.doi.org/10.15407/microbiolj83.06.095.

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Currently, a lot of researcher’s attention is devoted to the problem of microbiologically influenced corrosion (MIC), since it causes huge damages to the economy, initiating the destruction of oil and gas pipelines and other underground constructions. To protect industrial materials from MIC effects an organic chemical inhibitors are massively used. However, the problem of their use is associated with toxicity, dangerous for the environment that caused the need for development the alternative methods of MIC repression. At the review, the data about different types of inhibitors-biocides usage has provided. The chemical inhibitors features are given and the mechanisms of their protective action are considered. The screening results and use of alternative and eco-friendly methods for managing the effect of corrosion caused by sulfate-reducing bacteria (SRB) are highlighted. Methods of joint application of chemical inhibitors and enhancers, such as chelators, biosurfactants, which contribute to reducing the concentration of chemical inhibitors, are discussed. The possibility of disruption of the quorum sensing interaction in the bacterial community to prevent the biofilm formation is considered. The information about the use of natural plant extracts, food waste, as well as by-products of agro-industrial production to combat MIC is provided. The development of biological corrosion control methods (to combat MIC) is of great importance for creating the best alternative and eco-friendly approaches to managing the effect of corrosion caused by SRB. The analysis of the literature data indicates the need to find the best alternatives and environmentally friendly solutions.

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Li, Jianping, Xiaofeng Min, Xi Zheng, Shaohua Wang, Xuetao Xu, and Jinbao Peng. "Synthesis, Anti-Tyrosinase Activity, and Spectroscopic Inhibition Mechanism of Cinnamic Acid–Eugenol Esters." Molecules 28, no. 16 (August 9, 2023): 5969. http://dx.doi.org/10.3390/molecules28165969.

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Tyrosinase plays crucial roles in mediating the production of melanin pigment; thus, its inhibitors could be useful in preventing melanin-related diseases. To find potential tyrosinase inhibitors, a series of cinnamic acid–eugenol esters (c1~c29) was synthesized and their chemical structures were confirmed by 1H NMR, 13C NMR, HRMS, and FT-IR, respectively. The biological evaluation results showed that all compounds c1~c29 exhibited definite tyrosinase inhibitory activity; especially, compound c27 was the strongest tyrosinase inhibitor (IC50: 3.07 ± 0.26 μM), being ~4.6-fold stronger than the positive control, kojic acid (IC50: 14.15 ± 0.46 μM). Inhibition kinetic studies validated compound c27 as a reversible mixed-type inhibitor against tyrosinase. Three-dimensional fluorescence and circular dichroism (CD) spectra results indicated that compound c27 could change the conformation and secondary structure of tyrosinase. Fluorescence-quenching results showed that compound c27 quenched tyrosinase fluorescence in the static manner with one binding site. Molecular docking results also revealed the binding interactions between compound c27 and tyrosinase. Therefore, cinnamic acid–eugenol esters, especially c27, could be used as lead compounds to find potential tyrosinase inhibitors.

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Kimmich, R., and W. -C. Park. "Chemical Libraries Towards Protein Kinase Inhibitors." Combinatorial Chemistry & High Throughput Screening 6, no. 7 (November 1, 2003): 661–72. http://dx.doi.org/10.2174/138620703771981223.

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Clopper, Kevin C., and Dylan J. Taatjes. "Chemical inhibitors of transcription-associated kinases." Current Opinion in Chemical Biology 70 (October 2022): 102186. http://dx.doi.org/10.1016/j.cbpa.2022.102186.

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Callus, B. A., and D. L. Vaux. "Caspase inhibitors: viral, cellular and chemical." Cell Death & Differentiation 14, no. 1 (September 8, 2006): 73–78. http://dx.doi.org/10.1038/sj.cdd.4402034.

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Noble, Martin E. M., and Jane A. Endicott. "Chemical Inhibitors of Cyclin-Dependent Kinases." Pharmacology & Therapeutics 82, no. 2-3 (May 1999): 269–78. http://dx.doi.org/10.1016/s0163-7258(98)00051-5.

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Sessa, D. J., and P. E. Ghantous. "Chemical inactivation of soybean trypsin inhibitors." Journal of the American Oil Chemists' Society 64, no. 12 (December 1987): 1682–87. http://dx.doi.org/10.1007/bf02542503.

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Journal articles on the topic 'Chemical inhibitors'

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