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Fouad Bentiss - One of the best experts on this subject based on the ideXlab platform.
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thermodynamic characterization of metal dissolution and inhibitor adsorption processes in mild steel 3 5 bis 3 4 dimethoxyphenyl 4 amino 1 2 4 Triazole hydrochloric acid system
2014Co-Authors: M Tourabi, B Hammouti, K Nohair, Abdelhamid Nyassi, Charafeddine Jama, Fouad BentissAbstract:New 3,5-disubstituted-4-amino-1,2,4-Triazole Derivative, namely 3,5-bis(3,4-dimethoxyphenyl)-4-amino-1,2,4-Triazole (3,4MAT) was synthesised and its inhibitive action against the corrosion of mild steel in 1 M HCl solution was investigated at 308 K. The detailed study of 3,4-MAT was been performed using gravimetric measurements and polarisation curves method. Results show that 3,4-MAT is a good inhibitor and its inhibition efficiency reaches 98 % at·10 �3 M. Tafel polarisation study revealed that 3,4-MAT acts as a mixed type inhibitor. The inhibitor adsorption process in mild steel/3,4-MAT /hydrochloric acid system was studied at different temperatures (308-323 K) by means of weight loss measurements. The adsorption of 3,4MAT on steel surface obeyed Langmuir’s adsorption isotherm. The kinetic and thermodynamic parameters for mild steel corrosion and inhibitor adsorption, respectively, were determined and discussed
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electrochemical and xps studies of the corrosion inhibition of carbon steel in hydrochloric acid pickling solutions by 3 5 bis 2 thienylmethyl 4 amino 1 2 4 Triazole
Corrosion Science, 2013Co-Authors: M Tourabi, K Nohair, Charafeddine Jama, M Traisnel, Fouad BentissAbstract:Abstract Corrosion inhibition of carbon steel in normal hydrochloric acid solution at 30 °C by new 4-amino-1,2,4-Triazole Derivative, namely 3,5-bis(2-thienylmethyl)-4-amino-1,2,4-Triazole (2-TMAT) has been studied by electrochemical impedance spectroscopy (EIS) and polarization techniques. The experimental results have showed that this organic compound revealed a good corrosion inhibition and that the inhibition efficiency is increased with the inhibitor concentration. Two time constants determined by the charge-transfer and the adsorption of the inhibitor, respectively, can be readily outlined. Potentiodynamic polarization showed that 2-TMAT is a mixed type of inhibitor. The adsorption of 2-TMAT on the carbon steel surface in 1 M HCl solution obeyed to the Langmuir isotherm with a very high negative value of the standard Gibbs free energy of adsorption Δ G ads ° (chemisorption). X-ray photoelectron spectroscopy (XPS) analyses were carried out to establish the mechanism of corrosion inhibition of carbon steel in 1 M HCl medium by 3,5-bis(2-thienylmethyl)-4-amino-1,2,4-Triazole (2-TMAT).
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study of the mechanism and inhibiting efficiency of 3 5 bis 4 methylthiophenyl 4h 1 2 4 Triazole on mild steel corrosion in acidic media
Corrosion Science, 2002Co-Authors: M Lagrenee, Michel Traisnel, B Mernari, M Bouanis, Fouad BentissAbstract:Abstract The efficiency of a new Triazole Derivative, namely, 3,5-bis(4-methylthiophenyl)-4H-1,2,4-Triazole (4-MTHT) has been studied for corrosion inhibition of mild steel in 1 M hydrochloric acid (HCl) and 0.5 M sulphuric acid (H 2 SO 4 ). Corrosion inhibition was studied using electrochemical methods and weight loss measurements. These studies have shown that 4-MTHT was a very good inhibitor. 4-MTHT behaved better in 1 M HCl than in 0.5 M H 2 SO 4 and inhibition efficiencies up to 99% and 80% can be obtained in 1 M HCl and 0.5 M H 2 SO 4 , respectively. Activation energies ( E a ) in the presence and absence of 4-MTHT were obtained by measuring the temperature independence of the corrosion current. The potential of zero charge of mild steel was studied by ac impedance method, and the mechanism of adsorption has been discussed. The adsorption of 4-MTHT followed Langmuir's adsorption isotherm in both acids.
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a new Triazole Derivative as inhibitor of the acid corrosion of mild steel electrochemical studies weight loss determination sem and xps
Applied Surface Science, 1999Co-Authors: Fouad Bentiss, Michel Traisnel, L Gengembre, M LagreneeAbstract:Abstract The effect of addition of 2[5-(2-pyridyl)-1,2,4-triazol-3-yl] phenol (PPT) on mild steel dissolution in 1 M hydrochloric acid is studied through electrochemical impedance spectroscopy (EIS), potentiodynamic polarisation curves and gravimetric measurements. The obtained results showed that PPT revealed a good corrosion inhibition. Potentiodynamic polarisation studies indicate that PPT is a mixed-type inhibitor. The effect of temperature on the corrosion behaviour of mild steel in 1 M HCl with addition of 80 mg/l of PPT was studied in the temperature range from 25°C to 60°C. The associated activation corrosion and free adsorption energies have been determined. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) of the mild steel revealed that PPT is absorbed on the steel surface. PPT appears to function through the general adsorption mode following the Langmuir adsorption isotherm model.
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a new Triazole Derivative as inhibitor of the acid corrosion of mild steel electrochemical studies weight loss determination sem and xps
Applied Surface Science, 1999Co-Authors: Fouad Bentiss, M Traisnel, L Gengembre, M LagreneeAbstract:Abstract The effect of addition of 2[5-(2-pyridyl)-1,2,4-triazol-3-yl] phenol (PPT) on mild steel dissolution in 1 M hydrochloric acid is studied through electrochemical impedance spectroscopy (EIS), potentiodynamic polarisation curves and gravimetric measurements. The obtained results showed that PPT revealed a good corrosion inhibition. Potentiodynamic polarisation studies indicate that PPT is a mixed-type inhibitor. The effect of temperature on the corrosion behaviour of mild steel in 1 M HCl with addition of 80 mg/l of PPT was studied in the temperature range from 25°C to 60°C. The associated activation corrosion and free adsorption energies have been determined. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) of the mild steel revealed that PPT is absorbed on the steel surface. PPT appears to function through the general adsorption mode following the Langmuir adsorption isotherm model.
M Lagrenee - One of the best experts on this subject based on the ideXlab platform.
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study of the mechanism and inhibiting efficiency of 3 5 bis 4 methylthiophenyl 4h 1 2 4 Triazole on mild steel corrosion in acidic media
Corrosion Science, 2002Co-Authors: M Lagrenee, Michel Traisnel, B Mernari, M Bouanis, Fouad BentissAbstract:Abstract The efficiency of a new Triazole Derivative, namely, 3,5-bis(4-methylthiophenyl)-4H-1,2,4-Triazole (4-MTHT) has been studied for corrosion inhibition of mild steel in 1 M hydrochloric acid (HCl) and 0.5 M sulphuric acid (H 2 SO 4 ). Corrosion inhibition was studied using electrochemical methods and weight loss measurements. These studies have shown that 4-MTHT was a very good inhibitor. 4-MTHT behaved better in 1 M HCl than in 0.5 M H 2 SO 4 and inhibition efficiencies up to 99% and 80% can be obtained in 1 M HCl and 0.5 M H 2 SO 4 , respectively. Activation energies ( E a ) in the presence and absence of 4-MTHT were obtained by measuring the temperature independence of the corrosion current. The potential of zero charge of mild steel was studied by ac impedance method, and the mechanism of adsorption has been discussed. The adsorption of 4-MTHT followed Langmuir's adsorption isotherm in both acids.
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a new Triazole Derivative as inhibitor of the acid corrosion of mild steel electrochemical studies weight loss determination sem and xps
Applied Surface Science, 1999Co-Authors: Fouad Bentiss, Michel Traisnel, L Gengembre, M LagreneeAbstract:Abstract The effect of addition of 2[5-(2-pyridyl)-1,2,4-triazol-3-yl] phenol (PPT) on mild steel dissolution in 1 M hydrochloric acid is studied through electrochemical impedance spectroscopy (EIS), potentiodynamic polarisation curves and gravimetric measurements. The obtained results showed that PPT revealed a good corrosion inhibition. Potentiodynamic polarisation studies indicate that PPT is a mixed-type inhibitor. The effect of temperature on the corrosion behaviour of mild steel in 1 M HCl with addition of 80 mg/l of PPT was studied in the temperature range from 25°C to 60°C. The associated activation corrosion and free adsorption energies have been determined. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) of the mild steel revealed that PPT is absorbed on the steel surface. PPT appears to function through the general adsorption mode following the Langmuir adsorption isotherm model.
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a new Triazole Derivative as inhibitor of the acid corrosion of mild steel electrochemical studies weight loss determination sem and xps
Applied Surface Science, 1999Co-Authors: Fouad Bentiss, M Traisnel, L Gengembre, M LagreneeAbstract:Abstract The effect of addition of 2[5-(2-pyridyl)-1,2,4-triazol-3-yl] phenol (PPT) on mild steel dissolution in 1 M hydrochloric acid is studied through electrochemical impedance spectroscopy (EIS), potentiodynamic polarisation curves and gravimetric measurements. The obtained results showed that PPT revealed a good corrosion inhibition. Potentiodynamic polarisation studies indicate that PPT is a mixed-type inhibitor. The effect of temperature on the corrosion behaviour of mild steel in 1 M HCl with addition of 80 mg/l of PPT was studied in the temperature range from 25°C to 60°C. The associated activation corrosion and free adsorption energies have been determined. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) of the mild steel revealed that PPT is absorbed on the steel surface. PPT appears to function through the general adsorption mode following the Langmuir adsorption isotherm model.
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the corrosion inhibition of mild steel in acidic media by a new Triazole Derivative
Corrosion Science, 1999Co-Authors: Fouad Bentiss, M Lagrenee, Michel Traisnel, Jeanchristophe HornezAbstract:A new corrosion inhibitor, namely, 3,5-bis (2-thienyl)-4-amino-1,2,4-Triazoles (2-TAT) has been synthesised and its inhibiting action on the corrosion of mild steel in acid baths (1 M HCl and 0.5 M H2SO4) has been investigated by various corrosion monitoring techniques, such as corrosion weight loss tests and electrochemical impedance spectroscopy. The electrochemical study reveals that this compound is an anodic inhibitor. Changes in impedance parameters (Rt and Cdl) are indicative of the adsorption of 2-TAT on the metal surface, leading to the formation of a protective film which grows with increasing exposure time. 2-TAT is able to reduce the steel corrosion more effectively in 1 M HCl than in 0.5 M H2SO4. The adsorption of this inhibitor is also found to obey the Langmuir adsorption isotherm in both acids. 2-TAT is considered as a non-cytotoxic substance.
Naoyuki Kanzaki - One of the best experts on this subject based on the ideXlab platform.
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discovery of novel highly potent and selective matrix metalloproteinase mmp 13 inhibitors with a 1 2 4 triazol 3 yl moiety as a zinc binding group using a structure based design approach
Journal of Medicinal Chemistry, 2017Co-Authors: Hiroshi Nara, Akira Kaieda, Kenjiro Sato, Takako Naito, Hideyuki Mototani, Hideyuki Oki, Yoshio Yamamoto, Haruhiko Kuno, Takashi Santou, Naoyuki KanzakiAbstract:On the basis of a superposition study of X-ray crystal structures of complexes of quinazoline Derivative 1 and Triazole Derivative 2 with matrix metalloproteinase (MMP)-13 catalytic domain, a novel series of fused pyrimidine compounds which possess a 1,2,4-triazol-3-yl group as a zinc binding group (ZBG) was designed. Among the herein described and evaluated compounds, 31f exhibited excellent potency for MMP-13 (IC50 = 0.036 nM) and selectivities (greater than 1,500-fold) over other MMPs (MMP-1, -2, -3, -7, -8, -9, -10, and -14) and tumor necrosis factor-α converting enzyme (TACE). Furthermore, the inhibitor was shown to protect bovine nasal cartilage explants against degradation induced by interleukin-1 and oncostatin M. In this article, we report the discovery of extremely potent, highly selective, and orally bioavailable fused pyrimidine Derivatives that possess a 1,2,4-triazol-3-yl group as a novel ZBG for selective MMP-13 inhibition.
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Discovery of Novel, Highly Potent, and Selective Matrix Metalloproteinase (MMP)-13 Inhibitors with a 1,2,4-Triazol-3-yl Moiety as a Zinc Binding Group Using a Structure-Based Design Approach
2016Co-Authors: Hiroshi Nara, Akira Kaieda, Kenjiro Sato, Takako Naito, Hideyuki Mototani, Hideyuki Oki, Yoshio Yamamoto, Haruhiko Kuno, Takashi Santou, Naoyuki KanzakiAbstract:On the basis of a superposition study of X-ray crystal structures of complexes of quinazoline Derivative 1 and Triazole Derivative 2 with matrix metalloproteinase (MMP)-13 catalytic domain, a novel series of fused pyrimidine compounds which possess a 1,2,4-triazol-3-yl group as a zinc binding group (ZBG) was designed. Among the herein described and evaluated compounds, 31f exhibited excellent potency for MMP-13 (IC50 = 0.036 nM) and selectivities (greater than 1,500-fold) over other MMPs (MMP-1, -2, -3, -7, -8, -9, -10, and -14) and tumor necrosis factor-α converting enzyme (TACE). Furthermore, the inhibitor was shown to protect bovine nasal cartilage explants against degradation induced by interleukin-1 and oncostatin M. In this article, we report the discovery of extremely potent, highly selective, and orally bioavailable fused pyrimidine Derivatives that possess a 1,2,4-triazol-3-yl group as a novel ZBG for selective MMP-13 inhibition
Julio A Urbina - One of the best experts on this subject based on the ideXlab platform.
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activity of the new Triazole Derivative albaconazole against trypanosoma schizotrypanum cruzi in dog hosts
Antimicrobial Agents and Chemotherapy, 2004Co-Authors: Paulo Marcos Da Matta Guedes, Julio A Urbina, Marta De Lana, Luis Carlos Crocco Afonso, Vanja Maria Veloso, Washington L Tafuri, George L L Machadocoelho, Egler Chiari, Maria Terezinha BahiaAbstract:Albaconazole is an experimental Triazole Derivative with potent and broad-spectrum antifungal activity and a remarkably long half-life in dogs, monkeys, and humans. In the present work, we investigated the in vivo activity of this compound against two strains of the protozoan parasite Trypanosoma (Schizotrypanum) cruzi, the causative agent of Chagas' disease, using dogs as hosts. The T. cruzi strains used in the study were previously characterized (murine model) as susceptible (strain Berenice-78) and partially resistant (strain Y) to the drugs currently in clinical use, nifurtimox and benznidazole. Our results demonstrated that albaconazole is very effective in suppressing the proliferation of the parasite and preventing the death of infected animals. Furthermore, the parasitological, PCR, serological, and proliferative assay results indicated parasitological cure indices of 25 and 100% among animals inoculated with T. cruzi strain Y when they were treated with albaconazole at 1.5 mg/kg of body weight/day for 60 and 90 days, respectively. On the other hand, although albaconazole given at 1.5 mg/kg/day was very effective in suppressing the proliferation of the parasite in animals infected with the Berenice-78 T. cruzi strain, no parasitological cure was observed among them, even when a longer treatment period (150 doses) was used. In conclusion, our results demonstrate that albaconazole has trypanocidal activity in vivo and is capable of inducing radical parasitological cure, although natural resistance to this compound was also indicated. Furthermore, the compound can be used in long-term treatment schemes (60 to 150 days) with minimal toxicity and thus represents a potentially useful candidate for the treatment of human Chagas' disease.
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in vitro antiproliferative effects and mechanism of action of the new Triazole Derivative ur 9825 against the protozoan parasite trypanosoma schizotrypanum cruzi
Antimicrobial Agents and Chemotherapy, 2000Co-Authors: Julio A Urbina, Renee Lira, Gonzalo Visbal, Javier BartroliAbstract:We describe the in vitro antiproliferative effects of the new Triazole Derivative UR-9825 against the protozoan parasite Trypanosoma (Schizotrypanum) cruzi, the causative agent of Chagas' disease in Latin America. The compound was found to be extremely active against the cultured (epimastigote) form of the parasite, equivalent to that present in the reduviid vector, with a MIC of 30 nM, a concentration 33-fold lower than that required with the reference compound ketoconazole. At that MIC, growth arrest coincided with depletion of the parasite's 4,14-desmethyl endogenous sterols (ergosterol, 24-ethylcholesta-5,7,22-trien-3b-ol, and precursors) and their replacement by methylated sterols (lanosterol, 24-methylenedihydrolanosterol, and obtusifoliol), as revealed by high-resolution gas chromatography coupled with mass spectrometry. This indicated that the primary mechanism of action of UR-9825 was inhibition of the parasite's sterol C14α demethylase, as seen with other azole Derivatives. The phospholipid composition of growth-arrested epimastigotes was also altered, when compared to controls, with a significant increase in the content of phosphatidylethanolamine and phosphatidylserine and a concomitant reduction of the content of phosphatidylcholine. The clinically relevant intracellular amastigote form, grown in cultured Vero cells at 37°C, was even more sensitive to UR-9825, with a MIC of 10 nM, comparable to that for ketoconazole. The results showed that UR-9825 is among the most potent azole Derivatives tested against this parasite and support in vivo studies with this compound.
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activities of the Triazole Derivative sch 56592 posaconazole against drug resistant strains of the protozoan parasite trypanosoma schizotrypanum cruzi in immunocompetent and immunosuppressed murine hosts
Antimicrobial Agents and Chemotherapy, 2000Co-Authors: Judith Molina, Alvaro J Romanha, Olindo Assis Martinsfilho, Zigman Brener, David Loebenberg, Julio A UrbinaAbstract:We have studied the in vivo activity of the new experimental Triazole Derivative SCH 56592 (posaconazole) against a variety of strains of the protozoan parasite Trypanosoma (Schizotrypanum) cruzi, the causative agent of Chagas' disease, in both immunocompetent and immunosuppressed murine hosts. The T. cruzi strains used in the study were previously characterized as susceptible (CL), partially resistant (Y), or highly resistant (Colombiana, SC-28, and VL-10) to the drugs currently in clinical use, nifurtimox and benznidazole. Furthermore, all strains are completely resistant to conventional antifungal azoles, such as ketoconazole. In the first study, acute infections with the CL, Y, and Colombiana strains in both normal and cyclophosphamide-immunosuppressed mice were treated orally, starting 4 days postinfection (p.i.), for 20 consecutive daily doses. The results indicated that in immunocompetent animals SCH 56592 at 20 mg/kg of body weight/day provided protection (80 to 90%) against death caused by all strains, a level comparable or superior to that provided by the optimal dose of benznidazole (100 mg/kg/day). Evaluation of parasitological cure revealed that SCH 56592 was able to cure 90 to 100% of the surviving animals infected with the CL and Y strains and 50% of those which received the benznidazole- and nifurtimox-resistant Colombiana strain. Immunosuppression markedly reduced the mean survival time of untreated mice infected with any of the strains, but this was not observed for the groups which received SCH 56592 at 20 mg/kg/day or benznidazole at 100 mg/kg/day. However, the overall cure rates were higher for animals treated with SCH 56592 than among those treated with benznidazole. The results were confirmed in a second study, using the same model but a longer (43-dose) treatment period. Finally, a model for the chronic disease in which oral treatment was started 120 days p.i. and consisted of 20 daily consecutive doses was investigated. The results showed that SCH 56592 at 20 mg/kg/day was able to induce a statistically significant increase in survival of animals infected with all strains, while benznidazole at 100 mg/kg/day was able to increase survival only in animals infected with the Colombiana strain. Moreover, the Triazole was able to induce parasitological cures in 50 to 60% of surviving animals, irrespective of the infecting strain, while no cures were obtained with benznidazole. Taken together, the results demonstrate that SCH 56592 has in vivo trypanocidal activity, even against T. cruzi strains naturally resistant to nitrofurans, nitroimidazoles, and conventional antifungal azoles, and that this activity is retained to a large extent in immunosuppressed hosts.
Manami Kaneko - One of the best experts on this subject based on the ideXlab platform.
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design synthesis and evaluation of the highly selective and potent g protein coupled receptor kinase 2 grk2 inhibitor for the potential treatment of heart failure
Journal of Medicinal Chemistry, 2017Co-Authors: Tomohiro Okawa, Yoshio Aramaki, Mitsuo Yamamoto, Toshitake Kobayashi, Shoji Fukumoto, Yukio Toyoda, Tsutomu Henta, Akito Hata, Shota Ikeda, Manami KanekoAbstract:A novel class of therapeutic drug candidates for heart failure, highly potent and selective GRK2 inhibitors, exhibit potentiation of β-adrenergic signaling in vitro studies. Hydrazone Derivative 5 and 1,2,4-Triazole Derivative 24a were identified as hit compounds by HTS. New scaffold generation and SAR studies of all parts resulted in a 4-methyl-1,2,4-Triazole Derivative with an N-benzylcarboxamide moiety with highly potent activity toward GRK2 and selectivity over other kinases. In terms of subtype selectivity, these compounds showed enough selectivity against GRK1, 5, 6, and 7 with almost equipotent inhibition to GRK3. Our medicinal chemistry efforts led to the discovery of 115h (GRK2 IC50 = 18 nM), which was obtained the cocrystal structure with human GRK2 and an inhibitor of GRK2 that potentiates β-adrenergic receptor (βAR)-mediated cAMP accumulation and prevents internalization of βARs in β2AR-expressing HEK293 cells treated with isoproterenol. Therefore, 115h appears to be a novel class of therapeut...
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Design, Synthesis, and Evaluation of the Highly Selective and Potent G‑Protein-Coupled Receptor Kinase 2 (GRK2) Inhibitor for the Potential Treatment of Heart Failure
2017Co-Authors: Tomohiro Okawa, Yoshio Aramaki, Mitsuo Yamamoto, Toshitake Kobayashi, Shoji Fukumoto, Yukio Toyoda, Tsutomu Henta, Akito Hata, Shota Ikeda, Manami KanekoAbstract:A novel class of therapeutic drug candidates for heart failure, highly potent and selective GRK2 inhibitors, exhibit potentiation of β-adrenergic signaling in vitro studies. Hydrazone Derivative 5 and 1,2,4-Triazole Derivative 24a were identified as hit compounds by HTS. New scaffold generation and SAR studies of all parts resulted in a 4-methyl-1,2,4-Triazole Derivative with an N-benzylcarboxamide moiety with highly potent activity toward GRK2 and selectivity over other kinases. In terms of subtype selectivity, these compounds showed enough selectivity against GRK1, 5, 6, and 7 with almost equipotent inhibition to GRK3. Our medicinal chemistry efforts led to the discovery of 115h (GRK2 IC50 = 18 nM), which was obtained the cocrystal structure with human GRK2 and an inhibitor of GRK2 that potentiates β-adrenergic receptor (βAR)-mediated cAMP accumulation and prevents internalization of βARs in β2AR-expressing HEK293 cells treated with isoproterenol. Therefore, 115h appears to be a novel class of therapeutic for heart failure treatment
