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Salem M, Abdullah AH, Ibrahim NS, Zaki MEA, Elwahy AHM, Abdelhamid IA. Novel Scaffolds Based on Bis-thiazole Connected to Quinoxaline or Thienothiophene through 2-Phenoxy- N-arylacetamide Groups as New Hybrid Molecules: Synthesis, Antibacterial Activity, and Molecular Docking Investigations. ACS OMEGA 2023; 8:44312-44327. [PMID: 38027350 PMCID: PMC10666262 DOI: 10.1021/acsomega.3c07125] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Revised: 10/25/2023] [Accepted: 10/30/2023] [Indexed: 12/01/2023]
Abstract
The resistance of microorganisms to antimicrobials has endangered the health of many people across the world. Overcoming the resistance problem will require the invention of molecules with a new mechanism of action so that no cross-resistance with existing therapies occurs. Because of their powerful antibacterial activity against a wide spectrum of Gram-positive and Gram-negative bacterial strains, heterocyclic compounds are appealing candidates for medicinal chemists. In this regard, as unique hybrid compounds, we synthesized a novel family of bis-thiazoles linked to quinoxaline or thienothiophene via the 2-phenoxy-N-arylacetamide moiety. The target compounds were synthesized by reacting the relevant bis(α-haloketones) with the corresponding thiosemicarbazones in EtOH at reflux with a few drops of TEA. Under comparable reaction conditions, the isomeric bis(thiazoles) were synthesized by reacting the appropriate bis(thiosemicarbazone) with the respective α-haloketones. The structures of the novel compounds were confirmed using elements and spectral data. All of the synthesized compounds were tested for antibacterial activity in vitro. With an inhibitory zone width of 12 mm, compound 12a had the same activity as the reference medication tobramycin against Staphylococcus aureus. Compound 12b showed 20 mg/mL as a minimum inhibitory concentration (MIC) against Bacillus subtilis. Some of the synthesized compounds were tested via molecular docking against two bacterial proteins (dihydrofolate reductase and tyrosyl-tRNA synthetase).
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Affiliation(s)
- Mostafa
E. Salem
- Department
of Chemistry, College of Science, Imam Mohammad
Ibn Saud Islamic University (IMSIU), P.O. Box 90950, Riyadh 11623, Saudi Arabia
- Department
of Chemistry, Faculty of Science, Cairo
University, Giza 12613, Egypt
| | - Abbas H. Abdullah
- Department
of Chemistry, Faculty of Science, Cairo
University, Giza 12613, Egypt
| | - Nada S. Ibrahim
- Department
of Chemistry (Biochemistry Division), Faculty of Science, Cairo University, Giza 12613, Egypt
| | - Magdi E. A. Zaki
- Department
of Chemistry, College of Science, Imam Mohammad
Ibn Saud Islamic University (IMSIU), P.O. Box 90950, Riyadh 11623, Saudi Arabia
| | - Ahmed H. M. Elwahy
- Department
of Chemistry, Faculty of Science, Cairo
University, Giza 12613, Egypt
| | - Ismail A. Abdelhamid
- Department
of Chemistry, Faculty of Science, Cairo
University, Giza 12613, Egypt
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2
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Mazzone F, Simons VE, van Geelen L, Frank M, Mándi A, Kurtán T, Pfeffer K, Kalscheuer R. In Vitro Biological Activity of Natural Products from the Endophytic Fungus Paraboeremia selaginellae against Toxoplasma gondii. Antibiotics (Basel) 2022; 11:antibiotics11091176. [PMID: 36139955 PMCID: PMC9495004 DOI: 10.3390/antibiotics11091176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 08/26/2022] [Accepted: 08/29/2022] [Indexed: 11/16/2022] Open
Abstract
Toxoplasma gondii is an apicomplexan pathogen able to infect a wide range of warm-blooded animals, including humans, leading to toxoplasmosis. Current treatments for toxoplasmosis are associated with severe side-effects and a lack efficacy to eradicate chronic infection. Thus, there is an urgent need for developing novel, highly efficient agents against toxoplasmosis with low toxicity. For decades, natural products have been a useful source of novel bioactive compounds for the treatment of infectious pathogens. In the present study, we isolated eight natural products from the crude extract of the endophytic fungus Paraboeremia selaginellae obtained from the leaves of the plant Philodendron monstera. The natural products were tested for inhibiting Toxoplasma gondii proliferation, and their cytotoxicity was evaluated in different human cell lines. Six natural products showed antitoxoplasma activity with low or no cytotoxicity in human cell lines. Together, these findings indicate that biphenyl ethers, bioxanthracenes, and 5S,6S-phomalactone from P. selaginellae are potential candidates for novel anti-toxoplasma drugs.
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Affiliation(s)
- Flaminia Mazzone
- Institute of Medical Microbiology and Hospital Hygiene, Heinrich Heine University, 40225 Duesseldorf, Germany
| | - Viktor E. Simons
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich Heine University, 40225 Duesseldorf, Germany
| | - Lasse van Geelen
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich Heine University, 40225 Duesseldorf, Germany
| | - Marian Frank
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich Heine University, 40225 Duesseldorf, Germany
| | - Attila Mándi
- Department of Organic Chemistry, University of Debrecen, 4002 Debrecen, Hungary
| | - Tibor Kurtán
- Department of Organic Chemistry, University of Debrecen, 4002 Debrecen, Hungary
| | - Klaus Pfeffer
- Institute of Medical Microbiology and Hospital Hygiene, Heinrich Heine University, 40225 Duesseldorf, Germany
- Correspondence: (K.P.); (R.K.); Tel.: +49-211-8112459 (K.P.); +49-211-8114180 (R.K.)
| | - Rainer Kalscheuer
- Institute of Pharmaceutical Biology and Biotechnology, Heinrich Heine University, 40225 Duesseldorf, Germany
- Correspondence: (K.P.); (R.K.); Tel.: +49-211-8112459 (K.P.); +49-211-8114180 (R.K.)
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3
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Abstract
Purpose of Review Review building of programs to eliminate Toxoplasma infections. Recent Findings
Morbidity and mortality from toxoplasmosis led to programs in USA, Panama, and Colombia to facilitate understanding, treatment, prevention, and regional resources, incorporating student work. Summary Studies foundational for building recent, regional approaches/programs are reviewed. Introduction provides an overview/review of programs in Panamá, the United States, and other countries. High prevalence/risk of exposure led to laws mandating testing in gestation, reporting, and development of broad-based teaching materials about Toxoplasma. These were tested for efficacy as learning tools for high-school students, pregnant women, medical students, physicians, scientists, public health officials and general public. Digitized, free, smart phone application effectively taught pregnant women about toxoplasmosis prevention. Perinatal infection care programs, identifying true regional risk factors, and point-of-care gestational screening facilitate prevention and care. When implemented fully across all demographics, such programs present opportunities to save lives, sight, and cognition with considerable spillover benefits for individuals and societies. Supplementary Information The online version contains supplementary material available at 10.1007/s40124-022-00269-w.
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Building Programs to Eradicate Toxoplasmosis Part IV: Understanding and Development of Public Health Strategies and Advances “Take a Village”. CURRENT PEDIATRICS REPORTS 2022; 10:125-154. [PMID: 35991908 PMCID: PMC9379243 DOI: 10.1007/s40124-022-00268-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/29/2022] [Indexed: 11/12/2022]
Abstract
Purpose of Review Review international efforts to build a global public health initiative focused on toxoplasmosis with spillover benefits to save lives, sight, cognition and motor function benefiting maternal and child health. Recent Findings Multiple countries’ efforts to eliminate toxoplasmosis demonstrate progress and context for this review and new work. Summary Problems with potential solutions proposed include accessibility of accurate, inexpensive diagnostic testing, pre-natal screening and facilitating tools, missed and delayed neonatal diagnosis, restricted access, high costs, delays in obtaining medicines emergently, delayed insurance pre-approvals and high medicare copays taking considerable physician time and effort, harmful shortcuts being taken in methods to prepare medicines in settings where access is restricted, reluctance to perform ventriculoperitoneal shunts promptly when needed without recognition of potential benefit, access to resources for care, especially for marginalized populations, and limited use of recent advances in management of neurologic and retinal disease which can lead to good outcomes. Supplementary Information The online version contains supplementary material available at 10.1007/s40124-022-00268-x.
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5
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Wu RZ, Zhou HY, Song JF, Xia QH, Hu W, Mou XD, Li X. Chemotherapeutics for Toxoplasma gondii: Molecular Biotargets, Binding Modes, and Structure-Activity Relationship Investigations. J Med Chem 2021; 64:17627-17655. [PMID: 34894691 DOI: 10.1021/acs.jmedchem.1c01569] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Toxoplasmosis, an infectious zoonotic disease caused by the apicomplexan parasite Toxoplasma gondii (T. gondii), is a major worldwide health problem. However, there are currently no effective options (chemotherapeutic drugs or prophylactic vaccines) for treating chronic latent toxoplasmosis infection. Accordingly, seeking more effective and safer chemotherapeutics for combating this disease remains a long-term and challenging objective. In this paper, we summarize possible molecular biotargets, with an emphasis on those that are druggable and promising, including, without limitation, calcium-dependent protein kinase 1, bifunctional thymidylate synthase-dihydrofolate reductase, and farnesyl diphosphate synthase. Meanwhile, as important components of medicinal chemistry, the binding modes and structure-activity relationship profiles of the corresponding inhibitors were also illuminated. We anticipate that this information will be helpful for further identification of more effective chemotherapeutic interventions to prevent and treat zoonotic infections caused by T. gondii.
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Affiliation(s)
- Rong-Zhen Wu
- Institute of Materia Medica, Shandong First Medical University and Shandong Academy of Medical Sciences, no. 6699 Qingdao Road, Ji'nan, Shandong 250117, PR China
| | - Huai-Yu Zhou
- Department of Pathogen Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, no. 44 Wenhua Xi Road, Ji'nan, Shandong 250012, PR China
| | - Jing-Feng Song
- School of Pharmaceutical Sciences and Yunnan Provincial Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, no. 1168 Chunrong Xi Road, Kunming, Yunnan 650500, PR China
| | - Qiao-Hong Xia
- Department of Pathogen Biology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, no. 44 Wenhua Xi Road, Ji'nan, Shandong 250012, PR China
| | - Wei Hu
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, no. 72 Binhai Road of JiMo, Qingdao, Shandong 266237, PR China
| | - Xiao-Dong Mou
- Institute of Materia Medica, Shandong First Medical University and Shandong Academy of Medical Sciences, no. 6699 Qingdao Road, Ji'nan, Shandong 250117, PR China
| | - Xun Li
- Institute of Materia Medica, Shandong First Medical University and Shandong Academy of Medical Sciences, no. 6699 Qingdao Road, Ji'nan, Shandong 250117, PR China.,Key Laboratory of Forensic Toxicology, Ministry of Public Security, Beijing 100192, PR China
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6
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Rashid KO, Mohamed KS, Salam MAE, Abdel-Latif E, Fadda AA, Elmorsy MR. Synthesis of Novel Phenoxyacetamide Derivatives as Potential Insecticidal Agents Against the Cotton Leafworm, Spodoptera littoralis. Polycycl Aromat Compd 2021. [DOI: 10.1080/10406638.2021.2015400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Kaiwan O. Rashid
- Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt
| | - Khaled S. Mohamed
- Engineering Chemistry Department, Higher Institute for Engineering and Technology, New Damietta, Egypt
| | - M. Abd El Salam
- Plant protection Research Institute, ARC, Dokki, Giza, Egypt
| | - Ehab Abdel-Latif
- Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt
| | - Ahmed A. Fadda
- Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt
| | - Mohamed R. Elmorsy
- Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt
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7
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Deng Y, Mu H, Li HB, Fu LZ, Tang D, Wu T, Huang SH, Li CH. In Vitro Anti-Toxoplasma gondii Activity Evaluation of a New Series of Quinazolin-4(3H)-one Derivatives. Chem Biodivers 2021; 18:e2100687. [PMID: 34726832 DOI: 10.1002/cbdv.202100687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 11/01/2021] [Indexed: 12/27/2022]
Abstract
Toxoplasmosis post serious threaten to human health, leading to severely eye and brain disease, especially for immunocompromised patients and pregnant women. The multiple side effects and long dosing period of current main treatment regiments calls for high effective and low toxicity anti-toxoplasmosis drugs. Herein, we report our efforts to synthesize a series of 2-(piperazin-1-yl)quinazolin-4(3H)-one derivatives and investigate their activity against Toxoplasma gondii tachyzoites in vitro based on cell phenotype screening. Among the 26 compounds, 8w and 8x with diaryl ether moiety at the side chain of piperazine exhibited good efficacy to inhibit T. gondii, with IC50 values of 4 μM and 3 μM, respectively. Structure-activity relationship (SAR) studies implies that hydrophobic aryl at the side chain would be preferred for improvement of activity. Molecular docking study reveals these two compounds appeared high affinity to TgCDPK1 by interaction with the hydrophobic pocket of ATP-binding cleft.
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Affiliation(s)
- Yu Deng
- Institute of Veterinary Sciences & Pharmaceuticals, Chongqing Academy of Animal Sciences, 51 Changlong Avenue, Rongchang District, 402460, China
| | - Hao Mu
- Institute of Veterinary Sciences & Pharmaceuticals, Chongqing Academy of Animal Sciences, 51 Changlong Avenue, Rongchang District, 402460, China
| | - Hong-Bo Li
- Chengdu Hyperway Pharmaceuticals Co., Ltd., Chengdu, China
| | - Li-Zhi Fu
- Institute of Veterinary Sciences & Pharmaceuticals, Chongqing Academy of Animal Sciences, 51 Changlong Avenue, Rongchang District, 402460, China
| | - Da Tang
- Institute of Veterinary Sciences & Pharmaceuticals, Chongqing Academy of Animal Sciences, 51 Changlong Avenue, Rongchang District, 402460, China
| | - Tao Wu
- Institute of Veterinary Sciences & Pharmaceuticals, Chongqing Academy of Animal Sciences, 51 Changlong Avenue, Rongchang District, 402460, China
| | - Shu-Heng Huang
- College of Bioengineering, Chongqing University, Chongqing, China
| | - Cheng-Hong Li
- Institute of Veterinary Sciences & Pharmaceuticals, Chongqing Academy of Animal Sciences, 51 Changlong Avenue, Rongchang District, 402460, China
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8
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Deng Y, Wu T, Zhai SQ, Li CH. Recent progress on anti-Toxoplasma drugs discovery: Design, synthesis and screening. Eur J Med Chem 2019; 183:111711. [PMID: 31585276 DOI: 10.1016/j.ejmech.2019.111711] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 08/27/2019] [Accepted: 09/16/2019] [Indexed: 01/30/2023]
Abstract
Toxoplasma gondii severely threaten the health of immunocompromised patients and pregnant women as this parasite can cause several disease, including brain and eye disease. Current treatment for toxoplasmosis commonly have high cytotoxic side effects on host and require long durations ranging from one week to more than one year. The regiments lack efficacy to eradicate T. gondii tissue cysts to cure chromic infection results in the needs for long treatment and relapsing disease. In addition, there has not been approved drugs for treating the pregnant women infected by T. gondii. Moreover, Toxoplasma vaccine researches face a wide variety of challenges. Developing high efficient and low toxic agents against T. gondii is urgent and important. Over the last decade, tremendous progress have been made in identifying and developing novel compounds for the treatment of toxoplasmosis. This review summarized and discussed recent advances between 2009 and 2019 in exploring effective agents against T. gondii from five aspects of drug discovery.
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Affiliation(s)
- Yu Deng
- Institute of Veterinary Sciences & Pharmaceuticals, Chongqing Academy of Animal Sciences, Rongchang, 402460, China
| | - Tao Wu
- Institute of Veterinary Sciences & Pharmaceuticals, Chongqing Academy of Animal Sciences, Rongchang, 402460, China
| | - Shao-Qin Zhai
- Institute of Veterinary Sciences & Pharmaceuticals, Chongqing Academy of Animal Sciences, Rongchang, 402460, China
| | - Cheng-Hong Li
- Institute of Veterinary Sciences & Pharmaceuticals, Chongqing Academy of Animal Sciences, Rongchang, 402460, China.
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9
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Veale CGL. Unpacking the Pathogen Box-An Open Source Tool for Fighting Neglected Tropical Disease. ChemMedChem 2019; 14:386-453. [PMID: 30614200 DOI: 10.1002/cmdc.201800755] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Indexed: 12/13/2022]
Abstract
The Pathogen Box is a 400-strong collection of drug-like compounds, selected for their potential against several of the world's most important neglected tropical diseases, including trypanosomiasis, leishmaniasis, cryptosporidiosis, toxoplasmosis, filariasis, schistosomiasis, dengue virus and trichuriasis, in addition to malaria and tuberculosis. This library represents an ensemble of numerous successful drug discovery programmes from around the globe, aimed at providing a powerful resource to stimulate open source drug discovery for diseases threatening the most vulnerable communities in the world. This review seeks to provide an in-depth analysis of the literature pertaining to the compounds in the Pathogen Box, including structure-activity relationship highlights, mechanisms of action, related compounds with reported activity against different diseases, and, where appropriate, discussion on the known and putative targets of compounds, thereby providing context and increasing the accessibility of the Pathogen Box to the drug discovery community.
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Affiliation(s)
- Clinton G L Veale
- School of Chemistry and Physics, Pietermaritzburg Campus, University of KwaZulu-Natal, Private Bag X01, Scottsville, 3209, South Africa
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10
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Sun CH, Lu Y, Zhang Q, Lu R, Bao LQ, Shen MH, Xu HD. Selective S-arylation of 2-oxazolidinethiones and selective N-arylation of 2-benzoxazolinones/2-benzimidazolinones. Org Biomol Chem 2018; 15:4058-4063. [PMID: 28443868 DOI: 10.1039/c7ob00040e] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
There exist three possible patterns for the reaction of cyclic 2-oxazolidinethione and 2-benzoxazolidinethione with arynes, namely (a) S-arylation, (b) N-arylation, and (c) aryne insertion into the thiocarbonyl group (C[double bond, length as m-dash]S). Our studies demonstrate that S-arylation wins out affording S-aryl dihydrooxazoles. In contrast, for related reactions of cyclic 2-benzoxazolinone and 2-benzimidazolinone with arynes, it is found that N-arylation outcompetes O-arylation and aryne insertion into the C[double bond, length as m-dash]O group to give N-aryl 2-benzoxazolinones and N-aryl 2-benzimidazolinones.
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Affiliation(s)
- Chu-Han Sun
- School of Pharmaceutical Engineering and Life Science, Changzhou University, Changzhou, Jiangsu Province 213164, China.
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12
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Abstract
Now clear evidences are available to support the hypothesis that inflammation accelerates the conditions including events and molecules that reach to various types of cancers. Inflammation is a normal response to infection containing the innate and adaptive immune systems. However, when allowed to continue, unresolved, perturbation of cellular microenvironment takes place; therefore, it leads to adaptations in genes that are linked to cancer. In addition, a lot of data are accessible confirming the concept that tumour microenvironment is orchestrated by various inflammatory cells and goes to neoplastic process and finally invasion, migration and metastasis. However, infiltrations of leucocytes lead to angiogenesis, propagation and invasion. An inflammatory microenvironment that perhaps fostering impact of angiogenesis include cytokines, chemokines, enzymes and growth factors that play key role for expansion and invasion of cancer cells. This insight highlights the pathogenesis of inflammation-associated cancers and also touches and fosters the role of acetamides for the treatment and chemoprevention of carcinomas that are allied with inflammation.
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Affiliation(s)
- Priyanka Rani
- a Department of Chemistry , School of Sciences, IFTM University Moradabad , Uttar Pradesh , India
| | - Dilipkumar Pal
- b Department of Pharmaceutical Sciences , Guru Ghasidas Vishwavidyalaya (A Central University) , Koni, Bilaspur , CG , India
| | - Rahul Rama Hegde
- c Department of Pharmaceutics , School of Pharmaceutical Sciences, IFTM University Moradabad , Uttar Pradesh , India
| | - Syed Riaz Hashim
- d Department of Chemistry , School of Pharmaceutical Sciences, IFTM University Moradabad , Uttar Pradesh , India
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Montazeri M, Sharif M, Sarvi S, Mehrzadi S, Ahmadpour E, Daryani A. A Systematic Review of In vitro and In vivo Activities of Anti -Toxoplasma Drugs and Compounds (2006-2016). Front Microbiol 2017; 8:25. [PMID: 28163699 PMCID: PMC5247447 DOI: 10.3389/fmicb.2017.00025] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 01/05/2017] [Indexed: 11/23/2022] Open
Abstract
The currently available anti-Toxoplasma agents have serious limitations. This systematic review was performed to evaluate drugs and new compounds used for the treatment of toxoplasmosis. Data was systematically collected from published papers on the efficacy of drugs/compounds used against Toxoplasma gondii (T. gondii) globally during 2006-2016. The searched databases were PubMed, Google Scholar, Science Direct, ISI Web of Science, EBSCO, and Scopus. One hundred and eighteen papers were eligible for inclusion in this systematic review, which were both in vitro and in vivo studies. Within this review, 80 clinically available drugs and a large number of new compounds with more than 39 mechanisms of action were evaluated. Interestingly, many of the drugs/compounds evaluated against T. gondii act on the apicoplast. Therefore, the apicoplast represents as a potential drug target for new chemotherapy. Based on the current findings, 49 drugs/compounds demonstrated in vitro half-maximal inhibitory concentration (IC50) values of below 1 μM, but most of them were not evaluated further for in vivo effectiveness. However, the derivatives of the ciprofloxacin, endochin-like quinolones and 1-[4-(4-nitrophenoxy) phenyl] propane-1-one (NPPP) were significantly active against T. gondii tachyzoites both in vitro and in vivo. Thus, these compounds are promising candidates for future studies. Also, compound 32 (T. gondii calcium-dependent protein kinase 1 inhibitor), endochin-like quinolones, miltefosine, rolipram abolish, and guanabenz can be repurposed into an effective anti-parasitic with a unique ability to reduce brain tissue cysts (88.7, 88, 78, 74, and 69%, respectively). Additionally, no promising drugs are available for congenital toxoplasmosis. In conclusion, as current chemotherapy against toxoplasmosis is still not satisfactory, development of well-tolerated and safe specific immunoprophylaxis in relaxing the need of dependence on chemotherapeutics is a highly valuable goal for global disease control. However, with the increasing number of high-risk individuals, and absence of a proper vaccine, continued efforts are necessary for the development of novel treatment options against T. gondii. Some of the novel compounds reviewed here may represent good starting points for the discovery of effective new drugs. In further, bioinformatic and in silico studies are needed in order to identify new potential toxoplasmicidal drugs.
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Affiliation(s)
- Mahbobeh Montazeri
- Toxoplasmosis Research Center, Mazandaran University of Medical SciencesSari, Iran
- Student Research Committee, Mazandaran University of Medical SciencesSari, Iran
| | - Mehdi Sharif
- Toxoplasmosis Research Center, Mazandaran University of Medical SciencesSari, Iran
- Department of Parasitology and Mycology, Sari Medical School, Mazandaran University of Medical SciencesSari, Iran
| | - Shahabeddin Sarvi
- Toxoplasmosis Research Center, Mazandaran University of Medical SciencesSari, Iran
- Department of Parasitology and Mycology, Sari Medical School, Mazandaran University of Medical SciencesSari, Iran
| | - Saeed Mehrzadi
- Department of Pharmacology, School of Medicine, Iran University of Medical Sciences TehranIran
| | - Ehsan Ahmadpour
- Drug Applied Research Center, Tabriz University of Medical SciencesTabriz, Iran
| | - Ahmad Daryani
- Toxoplasmosis Research Center, Mazandaran University of Medical SciencesSari, Iran
- Department of Parasitology and Mycology, Sari Medical School, Mazandaran University of Medical SciencesSari, Iran
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14
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Human toxoplasmosis–Searching for novel chemotherapeutics. Biomed Pharmacother 2016; 82:677-84. [DOI: 10.1016/j.biopha.2016.05.041] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Revised: 05/25/2016] [Accepted: 05/26/2016] [Indexed: 01/22/2023] Open
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15
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Clinically Available Medicines Demonstrating Anti-Toxoplasma Activity. Antimicrob Agents Chemother 2015; 59:7161-9. [PMID: 26392504 DOI: 10.1128/aac.02009-15] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Toxoplasma gondii is an apicomplexan parasite of humans and other mammals, including livestock and companion animals. While chemotherapeutic regimens, including pyrimethamine and sulfadiazine regimens, ameliorate acute or recrudescent disease such as toxoplasmic encephalitis or ocular toxoplasmosis, these drugs are often toxic to the host. Moreover, no approved options are available to treat infected women who are pregnant. Lastly, no drug regimen has shown the ability to eradicate the chronic stage of infection, which is characterized by chemoresistant intracellular cysts that persist for the life of the host. In an effort to promote additional chemotherapeutic options, we now evaluate clinically available drugs that have shown efficacy in disease models but which lack clinical case reports. Ideally, less-toxic treatments for the acute disease can be identified and developed, with an additional goal of cyst clearance from human and animal hosts.
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Bertrand HC, Schaap M, Baird L, Georgakopoulos ND, Fowkes A, Thiollier C, Kachi H, Dinkova-Kostova AT, Wells G. Design, Synthesis, and Evaluation of Triazole Derivatives That Induce Nrf2 Dependent Gene Products and Inhibit the Keap1–Nrf2 Protein–Protein Interaction. J Med Chem 2015; 58:7186-94. [DOI: 10.1021/acs.jmedchem.5b00602] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Hélène C. Bertrand
- UCL
School of Pharmacy, University College London, 29/39 Brunswick Square, London, WC1N 1AX, United Kingdom
| | - Marjolein Schaap
- UCL
School of Pharmacy, University College London, 29/39 Brunswick Square, London, WC1N 1AX, United Kingdom
| | - Liam Baird
- Jacqui
Wood Cancer Centre, Division of Cancer Research, Medical Research
Institute, University of Dundee, Dundee, DD1 9SY, Scotland, United Kingdom
| | - Nikolaos D. Georgakopoulos
- UCL
School of Pharmacy, University College London, 29/39 Brunswick Square, London, WC1N 1AX, United Kingdom
| | - Adrian Fowkes
- UCL
School of Pharmacy, University College London, 29/39 Brunswick Square, London, WC1N 1AX, United Kingdom
| | - Clarisse Thiollier
- UCL
School of Pharmacy, University College London, 29/39 Brunswick Square, London, WC1N 1AX, United Kingdom
| | - Hiroko Kachi
- UCL
School of Pharmacy, University College London, 29/39 Brunswick Square, London, WC1N 1AX, United Kingdom
| | - Albena T. Dinkova-Kostova
- Jacqui
Wood Cancer Centre, Division of Cancer Research, Medical Research
Institute, University of Dundee, Dundee, DD1 9SY, Scotland, United Kingdom
- Departments
of Medicine and Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, United States
| | - Geoff Wells
- UCL
School of Pharmacy, University College London, 29/39 Brunswick Square, London, WC1N 1AX, United Kingdom
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Fatty acid metabolism in the Plasmodium apicoplast: Drugs, doubts and knockouts. Mol Biochem Parasitol 2015; 199:34-50. [DOI: 10.1016/j.molbiopara.2015.03.004] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Revised: 03/16/2015] [Accepted: 03/17/2015] [Indexed: 12/25/2022]
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18
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Triclosan and triclosan-loaded liposomal nanoparticles in the treatment of acute experimental toxoplasmosis. Exp Parasitol 2014; 149:54-64. [PMID: 25499511 DOI: 10.1016/j.exppara.2014.12.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 11/26/2014] [Accepted: 12/04/2014] [Indexed: 11/21/2022]
Abstract
Efficacy of triclosan (TS) and TS-loaded liposomes against the virulent strain of Toxoplasma gondii (T. gondii) was evaluated. Swiss albino mice were intraperitoneally infected with 10(4) tachyzoites of RH HXGPRT(-) strain of T. gondii, then were orally treated with 150 mg/kg TS or 100 mg/kg TS liposomes twice daily for 4 days. Mice mortality, peritoneal and liver parasite burdens, viability, infectivity and ultrastructural changes of peritoneal tachyzoites of infected treated mice were studied, in comparison with those of infected non-treated controls. Drug safety was biochemically assessed by measuring liver enzymes and thyroxin. Both TS and TS liposomes induced significant reduction in mice mortality, parasite burden, viability and infectivity of tachyzoites harvested from infected treated mice. Scanning electron microscopy of treated tachyzoites showed distorted shapes, reduced sizes, irregularities, surface protrusions, erosions and peeling besides apical region distortion. Transmission electron microscopy showed that treated tachyzoites were intracellularly distorted, had cytoplasmic vacuolation, discontinuous plasma membranes, nuclear abnormalities and disrupted internal structures. Besides, in TS liposomes-treated subgroup, most tachyzoites were seen intracellularly with complete disintegration of the parasite plasma and nuclear membranes, with complete destruction of the internal structures. Biochemical safety of TS and TS liposomes was proven. Accordingly, TS can be considered as a promising alternative to the standard therapy for treating acute murine toxoplasmosis. Liposomal formulation of TS enhanced its efficacy and allowed its use in a lower dose.
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Lancefield CS, Ojo OS, Tran F, Westwood NJ. Isolation of functionalized phenolic monomers through selective oxidation and C-O bond cleavage of the β-O-4 linkages in lignin. Angew Chem Int Ed Engl 2014; 54:258-62. [PMID: 25377996 DOI: 10.1002/anie.201409408] [Citation(s) in RCA: 236] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Indexed: 11/08/2022]
Abstract
Functionalized phenolic monomers have been generated and isolated from an organosolv lignin through a two-step depolymerization process. Chemoselective catalytic oxidation of β-O-4 linkages promoted by the DDQ/tBuONO/O2 system was achieved in model compounds, including polymeric models and in real lignin. The oxidized β-O-4 linkages were then cleaved on reaction with zinc. Compared to many existing methods, this protocol, which can be achieved in one pot, is highly selective, giving rise to a simple mixture of products that can be readily purified to give pure compounds. The functionality present in these products makes them potentially valuable building blocks.
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Affiliation(s)
- Christopher S Lancefield
- School of Chemistry and Biomedical Sciences Research Complex, University of St Andrews and EaStCHEM, North Haugh, St Andrews, Fife (UK)
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20
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Lancefield CS, Ojo OS, Tran F, Westwood NJ. Isolation of Functionalized Phenolic Monomers through Selective Oxidation and CO Bond Cleavage of the β‐O‐4 Linkages in Lignin. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201409408] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Christopher S. Lancefield
- School of Chemistry and Biomedical Sciences Research Complex, University of St Andrews and EaStCHEM, North Haugh, St Andrews, Fife (UK)
| | - O. Stephen Ojo
- School of Chemistry and Biomedical Sciences Research Complex, University of St Andrews and EaStCHEM, North Haugh, St Andrews, Fife (UK)
| | - Fanny Tran
- School of Chemistry and Biomedical Sciences Research Complex, University of St Andrews and EaStCHEM, North Haugh, St Andrews, Fife (UK)
| | - Nicholas J. Westwood
- School of Chemistry and Biomedical Sciences Research Complex, University of St Andrews and EaStCHEM, North Haugh, St Andrews, Fife (UK)
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21
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Stec J, Vilchèze C, Lun S, Perryman AL, Wang X, Freundlich JS, Bishai W, Jacobs WR, Kozikowski AP. Biological evaluation of potent triclosan-derived inhibitors of the enoyl-acyl carrier protein reductase InhA in drug-sensitive and drug-resistant strains of Mycobacterium tuberculosis. ChemMedChem 2014; 9:2528-37. [PMID: 25165007 PMCID: PMC4213240 DOI: 10.1002/cmdc.201402255] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2014] [Indexed: 11/09/2022]
Abstract
New triclosan (TRC) analogues were evaluated for their activity against the enoyl-acyl carrier protein reductase InhA in Mycobacterium tuberculosis (Mtb). TRC is a well-known inhibitor of InhA, and specific modifications to its positions 5 and 4' afforded 27 derivatives; of these compounds, seven derivatives showed improved potency over that of TRC. These analogues were active against both drug-susceptible and drug-resistant Mtb strains. The most active compound in this series, 4-(n-butyl)-1,2,3-triazolyl TRC derivative 3, had an MIC value of 0.6 μg mL(-1) (1.5 μM) against wild-type Mtb. At a concentration equal to its MIC, this compound inhibited purified InhA by 98 %, and showed an IC50 value of 90 nM. Compound 3 and the 5-methylisoxazole-modified TRC 14 were able to inhibit the biosynthesis of mycolic acids. Furthermore, mc(2) 4914, an Mtb strain overexpressing inhA, was found to be less susceptible to compounds 3 and 14, supporting the notion that InhA is the likely molecular target of the TRC derivatives presented herein.
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Affiliation(s)
- Jozef Stec
- Drug Discovery Program, Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois 60612, United States, Fax: +1-312-996-7107
- Department of Pharmaceutical Sciences, College of Pharmacy, Chicago State University, 9501 S. King Drive, Chicago, Illinois 60628, United States
| | - Catherine Vilchèze
- Howard Hughes Medical Institute, Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York 10461, United States
| | - Shichun Lun
- Center for Tuberculosis Research, Department of Medicine, Division of Infectious Disease, Johns Hopkins School of Medicine, Baltimore, MD 21231-1044, United States
| | - Alexander L. Perryman
- Center for Emerging & Re-emerging Pathogens, Division of Infectious, Diseases, Department of Medicine, Rutgers University-New Jersey Medical School, 185 South Orange Avenue, Newark, NJ 07103, United States
| | - Xin Wang
- Center for Emerging & Re-emerging Pathogens, Division of Infectious, Diseases, Department of Medicine, Rutgers University-New Jersey Medical School, 185 South Orange Avenue, Newark, NJ 07103, United States
| | - Joel S. Freundlich
- Center for Emerging & Re-emerging Pathogens, Division of Infectious, Diseases, Department of Medicine, Rutgers University-New Jersey Medical School, 185 South Orange Avenue, Newark, NJ 07103, United States
- Department of Pharmacology and Physiology, Rutgers University-New Jersey Medical School, 185 South Orange Avenue, Newark, NJ 07103, United States
| | - William Bishai
- Center for Tuberculosis Research, Department of Medicine, Division of Infectious Disease, Johns Hopkins School of Medicine, Baltimore, MD 21231-1044, United States
| | - William R. Jacobs
- Howard Hughes Medical Institute, Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York 10461, United States
| | - Alan P. Kozikowski
- Drug Discovery Program, Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois 60612, United States, Fax: +1-312-996-7107
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22
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Sambiagio C, Munday RH, Marsden SP, Blacker AJ, McGowan PC. Picolinamides as Effective Ligands for Copper-Catalysed Aryl Ether Formation: Structure-Activity Relationships, Substrate Scope and Mechanistic Investigations. Chemistry 2014; 20:17606-15. [DOI: 10.1002/chem.201404275] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Indexed: 11/05/2022]
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23
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Sippel KH, Vyas NK, Zhang W, Sankaran B, Quiocho FA. Crystal structure of the human fatty acid synthase enoyl-acyl carrier protein-reductase domain complexed with triclosan reveals allosteric protein-protein interface inhibition. J Biol Chem 2014; 289:33287-95. [PMID: 25301948 DOI: 10.1074/jbc.m114.608547] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Human fatty acid synthase (FAS) is a large, multidomain protein that synthesizes long chain fatty acids. Because these fatty acids are primarily provided by diet, FAS is normally expressed at low levels; however, it is highly up-regulated in many cancers. Human enoyl-acyl carrier protein-reductase (hER) is one of the FAS catalytic domains, and its inhibition by drugs like triclosan (TCL) can increase cytotoxicity and decrease drug resistance in cancer cells. We have determined the structure of hER in the presence and absence of TCL. TCL was not bound in the active site, as predicted, but rather at the protein-protein interface (PPI). TCL binding induces a dimer orientation change that causes downstream structural rearrangement in critical active site residues. Kinetics studies indicate that TCL is capable of inhibiting the isolated hER domain with an IC50 of ∼ 55 μM. Given the hER-TCL structure and the inhibition observed in the hER domain, it seems likely that TCL is observed in the physiologically relevant binding site and that it acts as an allosteric PPI inhibitor. TCL may be a viable scaffold for the development of anti-cancer PPI FAS inhibitors.
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Affiliation(s)
- Katherine H Sippel
- From the Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030 and
| | - Nand K Vyas
- From the Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030 and
| | - Wei Zhang
- From the Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030 and
| | - Banumathi Sankaran
- the Berkeley Center for Structural Biology, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Florante A Quiocho
- From the Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030 and
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24
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Rani P, Pal D, Hegde RR, Hashim SR. Anticancer, anti-inflammatory, and analgesic activities of synthesized 2-(substituted phenoxy) acetamide derivatives. BIOMED RESEARCH INTERNATIONAL 2014; 2014:386473. [PMID: 25197642 PMCID: PMC4150437 DOI: 10.1155/2014/386473] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 07/22/2014] [Accepted: 07/29/2014] [Indexed: 11/17/2022]
Abstract
The aphorism was to develop new chemical entities as potential anticancer, anti-inflammatory, and analgesic agents. The Leuckart synthetic pathway was utilized in development of novel series of 2-(substituted phenoxy)-N-(1-phenylethyl)acetamide derivatives. The compounds containing 1-phenylethylamine as basic moiety attached to substituted phenols were assessed for their anticancer activity against MCF-7 (breast cancer), SK-N-SH (neuroblastoma), anti-inflammatory activity, and analgesic activity. These investigations revealed that synthesized products 3a-j with halogens on the aromatic ring favors as the anticancer and anti-inflammatory activity. Among all, compound 3c N-(1-(4-chlorophenyl)ethyl)-2-(4-nitrophenoxy)acetamide exhibited anticancer, anti-inflammatory, and analgesic activities. In conclusion, 3c may have potential to be developed into a therapeutic agent.
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Affiliation(s)
- Priyanka Rani
- Department of Chemistry, School of Sciences, IFTM University, Moradabad, Uttar Pradesh, India
| | - Dilipkumar Pal
- Department of Pharmaceutical Sciences, Guru Ghasidas Vishwavidyalaya (A Central University), Koni, Bilaspur, Chhattisgarh 495 009, India
| | - Rahul Rama Hegde
- Department of Pharmaceutics, School of Pharmaceutical Sciences, IFTM University, Moradabad, Uttar Pradesh, India
| | - Syed Riaz Hashim
- Department of Chemistry, School of Pharmaceutical Sciences, IFTM University, Moradabad, Uttar Pradesh, India
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25
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Repurposing the open access malaria box to discover potent inhibitors of Toxoplasma gondii and Entamoeba histolytica. Antimicrob Agents Chemother 2014; 58:5848-54. [PMID: 25049259 DOI: 10.1128/aac.02541-14] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Toxoplasmosis and amebiasis are important public health concerns worldwide. The drugs currently available to control these diseases have proven limitations. Therefore, innovative approaches should be adopted to identify and develop new leads from novel scaffolds exhibiting novel modes of action. In this paper, we describe results from the screening of compounds in the Medicines for Malaria Venture (MMV) open access Malaria Box in a search for new anti-Toxoplasma and anti-Entamoeba agents. Standard in vitro phenotypic screening procedures were adopted to assess their biological activities. Seven anti-Toxoplasma compounds with a 50% inhibitory concentration (IC50) of <5 μM and selectivity indexes (SI) of >6 were identified. The most interesting compound was MMV007791, a piperazine acetamide, which has an IC50 of 0.19 μM and a selectivity index of >157. Also, we identified two compounds, MMV666600 and MMV006861, with modest activities against Entamoeba histolytica, with IC50s of 10.66 μM and 15.58 μM, respectively. The anti-Toxoplasma compounds identified in this study belong to scaffold types different from those of currently used drugs, underscoring their novelty and potential as starting points for the development of new antitoxoplasmosis drugs with novel modes of action.
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26
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Applications of structure-based design to antibacterial drug discovery. Bioorg Chem 2014; 55:69-76. [PMID: 24962384 DOI: 10.1016/j.bioorg.2014.05.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 05/15/2014] [Accepted: 05/15/2014] [Indexed: 11/21/2022]
Abstract
In recent years bacterial resistance has been observed against many of our current antibiotics, for instance most worryingly against the cephalosporins which are typically the last line of defence against many bacterial infections. Additionally the failure of high throughput screening in the discovery of new antibacterial drug leads has led to a decline in the number of antibacterial agents reaching the market. Alternative methods of drug discovery including structure based drug design are needed to meet the threats caused by the emergence of resistance. In this review we explore the latest advancements in the identification of new antibacterial agents through the use of a number of structure based drug design programs.
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27
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Afanador GA, Muench SP, McPhillie M, Fomovska A, Schön A, Zhou Y, Cheng G, Stec J, Freundlich JS, Shieh HM, Anderson JW, Jacobus DP, Fidock DA, Kozikowski AP, Fishwick CW, Rice DW, Freire E, McLeod R, Prigge ST. Discrimination of potent inhibitors of Toxoplasma gondii enoyl-acyl carrier protein reductase by a thermal shift assay. Biochemistry 2013; 52:9155-66. [PMID: 24295325 DOI: 10.1021/bi400945y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Many microbial pathogens rely on a type II fatty acid synthesis (FASII) pathway that is distinct from the type I pathway found in humans. Enoyl-acyl carrier protein reductase (ENR) is an essential FASII pathway enzyme and the target of a number of antimicrobial drug discovery efforts. The biocide triclosan is established as a potent inhibitor of ENR and has been the starting point for medicinal chemistry studies. We evaluated a series of triclosan analogues for their ability to inhibit the growth of Toxoplasma gondii, a pervasive human pathogen, and its ENR enzyme (TgENR). Several compounds that inhibited TgENR at low nanomolar concentrations were identified but could not be further differentiated because of the limited dynamic range of the TgENR activity assay. Thus, we adapted a thermal shift assay (TSA) to directly measure the dissociation constant (Kd) of the most potent inhibitors identified in this study as well as inhibitors from previous studies. Furthermore, the TSA allowed us to determine the mode of action of these compounds in the presence of the reduced nicotinamide adenine dinucleotide (NADH) or nicotinamide adenine dinucleotide (NAD⁺) cofactor. We found that all of the inhibitors bind to a TgENR-NAD⁺ complex but that they differed in their dependence on NAD⁺ concentration. Ultimately, we were able to identify compounds that bind to the TgENR-NAD⁺ complex in the low femtomolar range. This shows how TSA data combined with enzyme inhibition, parasite growth inhibition data, and ADMET predictions allow for better discrimination between potent ENR inhibitors for the future development of medicine.
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Affiliation(s)
- Gustavo A Afanador
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health , Baltimore, Maryland 21205, United States
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28
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Metabolic reconstruction identifies strain‐specific regulation of virulence in
Toxoplasma gondii. Mol Syst Biol 2013; 9:708. [PMID: 24247825 PMCID: PMC4039375 DOI: 10.1038/msb.2013.62] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 10/10/2013] [Indexed: 12/27/2022] Open
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29
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Stec J, Fomovska A, Afanador GA, Muench SP, Zhou Y, Lai BS, El Bissati K, Hickman MR, Lee PJ, Leed SE, Auschwitz JM, Sommervile C, Woods S, Roberts CW, Rice D, Prigge ST, McLeod R, Kozikowski AP. Modification of triclosan scaffold in search of improved inhibitors for enoyl-acyl carrier protein (ACP) reductase in Toxoplasma gondii. ChemMedChem 2013; 8:1138-60. [PMID: 23776166 DOI: 10.1002/cmdc.201300050] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 04/26/2013] [Indexed: 11/08/2022]
Abstract
Through our focused effort to discover new and effective agents against toxoplasmosis, a structure-based drug design approach was used to develop a series of potent inhibitors of the enoyl-acyl carrier protein (ACP) reductase (ENR) enzyme in Toxoplasma gondii (TgENR). Modifications to positions 5 and 4' of the well-known ENR inhibitor triclosan afforded a series of 29 new analogues. Among the resulting compounds, many showed high potency and improved physicochemical properties in comparison with the lead. The most potent compounds 16 a and 16 c have IC50 values of 250 nM against Toxoplasma gondii tachyzoites without apparent toxicity to the host cells. Their IC50 values against recombinant TgENR were found to be 43 and 26 nM, respectively. Additionally, 11 other analogues in this series had IC50 values ranging from 17 to 130 nM in the enzyme-based assay. With respect to their excellent in vitro activity as well as improved drug-like properties, the lead compounds 16 a and 16 c are deemed to be excellent starting points for the development of new medicines to effectively treat Toxoplasma gondii infections.
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Affiliation(s)
- Jozef Stec
- Drug Discovery Program, Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 833 South Wood Street, Chicago, IL 60612, USA
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30
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Liu Q, Lu Z, Ren W, Shen K, Wang Y, Xu Q. Efficient Synthesis of Unsymmetrical Heteroaryl Ethers by a Transition Metal-Free CO Cross-Coupling Reaction of Activated and Unactivated Heteroaryl Chlorides with Alcohols and Phenols. CHINESE J CHEM 2013. [DOI: 10.1002/cjoc.201300120] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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31
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Development of a triclosan scaffold which allows for adaptations on both the A- and B-ring for transport peptides. Bioorg Med Chem Lett 2013; 23:3551-5. [PMID: 23664871 DOI: 10.1016/j.bmcl.2013.04.035] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Revised: 04/09/2013] [Accepted: 04/13/2013] [Indexed: 01/07/2023]
Abstract
The enoyl acyl-carrier protein reductase (ENR) enzyme is harbored within the apicoplast of apicomplexan parasites providing a significant challenge for drug delivery, which may be overcome through the addition of transductive peptides, which facilitates crossing the apicoplast membranes. The binding site of triclosan, a potent ENR inhibitor, is occluded from the solvent making the attachment of these linkers challenging. Herein, we have produced 3 new triclosan analogs with bulky A- and B-ring motifs, which protrude into the solvent allowing for the future attachment of molecular transporters for delivery.
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32
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Cheng G, Muench SP, Zhou Y, Afanador GA, Mui EJ, Fomovska A, Lai BS, Prigge ST, Woods S, Roberts CW, Hickman MR, Lee PJ, Leed SE, Auschwitz JM, Rice DW, McLeod R. Design, synthesis, and biological activity of diaryl ether inhibitors of Toxoplasma gondii enoyl reductase. Bioorg Med Chem Lett 2013; 23:2035-43. [PMID: 23453069 PMCID: PMC3625046 DOI: 10.1016/j.bmcl.2013.02.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2012] [Revised: 01/24/2013] [Accepted: 02/01/2013] [Indexed: 01/09/2023]
Abstract
Triclosan is a potent inhibitor of Toxoplasma gondii enoyl reductase (TgENR), which is an essential enzyme for parasite survival. In view of triclosan's poor druggability, which limits its therapeutic use, a new set of B-ring modified analogs were designed to optimize its physico-chemical properties. These derivatives were synthesized and evaluated by in vitro assay and TgENR enzyme assay. Some analogs display improved solubility, permeability and a comparable MIC50 value to that of triclosan. Modeling of these inhibitors revealed the same overall binding mode with the enzyme as triclosan, but the B-ring modifications have additional interactions with the strongly conserved Asn130.
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Affiliation(s)
- Gang Cheng
- Drug Discovery Program, Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois, 60612, United States
| | | | - Ying Zhou
- Department of Ophthalmology and Visual Sciences, Pediatrics (Infectious Diseases), Committees on Genetics, Immunology, and Molecular Medicine, Institute of Genomics and Systems Biology, and The College, The University of Chicago, Chicago, Illinois 60637, United States
| | - Gustavo A. Afanador
- Johns Hopkins School of Public Health Rm. E5132, 615 N. Wolfe St. Baltimore MD 21205, United States
| | - Ernest J. Mui
- Department of Ophthalmology and Visual Sciences, Pediatrics (Infectious Diseases), Committees on Genetics, Immunology, and Molecular Medicine, Institute of Genomics and Systems Biology, and The College, The University of Chicago, Chicago, Illinois 60637, United States
| | - Alina Fomovska
- Department of Ophthalmology and Visual Sciences, Pediatrics (Infectious Diseases), Committees on Genetics, Immunology, and Molecular Medicine, Institute of Genomics and Systems Biology, and The College, The University of Chicago, Chicago, Illinois 60637, United States
| | - Bo Shiun Lai
- Department of Ophthalmology and Visual Sciences, Pediatrics (Infectious Diseases), Committees on Genetics, Immunology, and Molecular Medicine, Institute of Genomics and Systems Biology, and The College, The University of Chicago, Chicago, Illinois 60637, United States
| | - Sean T. Prigge
- Johns Hopkins School of Public Health Rm. E5132, 615 N. Wolfe St. Baltimore MD 21205, United States
| | - Stuart Woods
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow, G4 0RE, U.K
| | - Craig W. Roberts
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, 161 Cathedral Street, Glasgow, G4 0RE, U.K
| | - Mark R. Hickman
- Department of Discovery, Division of Experimental Therapeutics Walter Reed Army Institute of Research, Rm 2N61 503 Robert Grant Avenue, Silver Spring, MD 20910
| | - Patty J. Lee
- Department of Discovery, Division of Experimental Therapeutics Walter Reed Army Institute of Research, Rm 2N61 503 Robert Grant Avenue, Silver Spring, MD 20910
| | - Susan E. Leed
- Department of Discovery, Division of Experimental Therapeutics Walter Reed Army Institute of Research, Rm 2N61 503 Robert Grant Avenue, Silver Spring, MD 20910
| | - Jennifer M. Auschwitz
- Department of Discovery, Division of Experimental Therapeutics Walter Reed Army Institute of Research, Rm 2N61 503 Robert Grant Avenue, Silver Spring, MD 20910
| | - David W. Rice
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, U.K
| | - Rima McLeod
- Department of Ophthalmology and Visual Sciences, Pediatrics (Infectious Diseases), Committees on Genetics, Immunology, and Molecular Medicine, Institute of Genomics and Systems Biology, and The College, The University of Chicago, Chicago, Illinois 60637, United States
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33
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Schrader FC, Glinca S, Sattler JM, Dahse HM, Afanador GA, Prigge ST, Lanzer M, Mueller AK, Klebe G, Schlitzer M. Novel type II fatty acid biosynthesis (FAS II) inhibitors as multistage antimalarial agents. ChemMedChem 2013; 8:442-61. [PMID: 23341167 DOI: 10.1002/cmdc.201200407] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Indexed: 11/09/2022]
Abstract
Malaria is a potentially fatal disease caused by Plasmodium parasites and poses a major medical risk in large parts of the world. The development of new, affordable antimalarial drugs is of vital importance as there are increasing reports of resistance to the currently available therapeutics. In addition, most of the current drugs used for chemoprophylaxis merely act on parasites already replicating in the blood. At this point, a patient might already be suffering from the symptoms associated with the disease and could additionally be infectious to an Anopheles mosquito. These insects act as a vector, subsequently spreading the disease to other humans. In order to cure not only malaria but prevent transmission as well, a drug must target both the blood- and pre-erythrocytic liver stages of the parasite. P. falciparum (Pf) enoyl acyl carrier protein (ACP) reductase (ENR) is a key enzyme of plasmodial type II fatty acid biosynthesis (FAS II). It has been shown to be essential for liver-stage development of Plasmodium berghei and is therefore qualified as a target for true causal chemoprophylaxis. Using virtual screening based on two crystal structures of PfENR, we identified a structurally novel class of FAS inhibitors. Subsequent chemical optimization yielded two compounds that are effective against multiple stages of the malaria parasite. These two most promising derivatives were found to inhibit blood-stage parasite growth with IC(50) values of 1.7 and 3.0 μM and lead to a more prominent developmental attenuation of liver-stage parasites than the gold-standard drug, primaquine.
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Affiliation(s)
- Florian C Schrader
- Institut für Pharmazeutische Chemie, Philipps Universität Marburg, Marbacher Weg 6, 35032 Marburg, Germany
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Abstract
INTRODUCTION Toxoplasma gondii, the agent that causes toxoplasmosis, is an opportunistic parasite that infects many mammalian species. It is an obligate intracellular parasite that causes severe congenital neurological and ocular disease mostly in immunocompromised humans. The current regimen of therapy includes only a few medications that often lead to hypersensitivity and toxicity. In addition, there are no vaccines available to prevent the transmission of this agent. Therefore, safer and more effective medicines to treat toxoplasmosis are urgently needed. AREAS COVERED The author presents in silico and in vitro strategies that are currently used to screen for novel targets and unique chemotypes against T. gondii. Furthermore, this review highlights the screening technologies and characterization of some novel targets and new chemical entities that could be developed into highly efficacious treatments for toxoplasmosis. EXPERT OPINION A number of diverse methods are being used to design inhibitors against T. gondii. These include ligand-based methods, in which drugs that have been shown to be efficacious against other Apicomplexa parasites can be repurposed to identify lead molecules against T. gondii. In addition, structure-based methods use currently available repertoire of structural information in various databases to rationally design small-molecule inhibitors of T. gondii. Whereas the screening methods have their advantages and limitations, a combination of methods is ideally suited to design small-molecule inhibitors of complex parasites such as T. gondii.
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Affiliation(s)
- Sandhya Kortagere
- Drexel University College of Medicine, Institute for Molecular Medicine, Department of Microbiology and Immunology, 2900, Queen Lane, PA 19129, USA.
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Qidwai T, Khan F. Antimalarial Drugs and Drug Targets Specific to Fatty Acid Metabolic Pathway of Plasmodium falciparum. Chem Biol Drug Des 2012; 80:155-72. [DOI: 10.1111/j.1747-0285.2012.01389.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Hirschbeck MW, Kuper J, Lu H, Liu N, Neckles C, Shah S, Wagner S, Sotriffer CA, Tonge PJ, Kisker C. Structure of the Yersinia pestis FabV enoyl-ACP reductase and its interaction with two 2-pyridone inhibitors. Structure 2012; 20:89-100. [PMID: 22244758 DOI: 10.1016/j.str.2011.07.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Revised: 07/19/2011] [Accepted: 07/20/2011] [Indexed: 01/03/2023]
Abstract
The recently discovered FabV enoyl-ACP reductase, which catalyzes the last step of the bacterial fatty acid biosynthesis (FAS-II) pathway, is a promising but unexploited drug target against the reemerging pathogen Yersinia pestis. The structure of Y. pestis FabV in complex with its cofactor reveals that the enzyme features the common architecture of the short-chain dehydrogenase reductase superfamily, but contains additional structural elements that are mostly folded around the usually flexible substrate-binding loop, thereby stabilizing it in a very tight conformation that seals the active site. The structures of FabV in complex with NADH and two newly developed 2-pyridone inhibitors provide insights for the development of new lead compounds, and suggest a mechanism by which the substrate-binding loop opens to admit the inhibitor, a motion that could also be coupled to the interaction of FabV with the acyl-carrier protein substrate.
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Affiliation(s)
- Maria W Hirschbeck
- Rudolf Virchow Center for Experimental Biomedicine, Institute for Structural Biology, Josef-Schneider-Strasse 2, University of Würzburg, D-97080 Würzburg, Germany
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Ang W, Lin YN, Yang T, Yang JZ, Pi WY, Yang YH, Luo YF, Deng Y, Wei YQ. Synthesis and biological evaluation of 2-(3-fluoro-4-nitro phenoxy)-n-phenylacetamide derivatives as novel potential affordable antitubercular agents. Molecules 2012; 17:2248-58. [PMID: 22357321 PMCID: PMC6268079 DOI: 10.3390/molecules17022248] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 02/20/2012] [Accepted: 02/20/2012] [Indexed: 11/16/2022] Open
Abstract
A novel series of 2-(3-fluoro-4-nitrophenoxy)-N-phenylacetamide compounds were designed, synthesized and in vitro assessed for their antitubercular activities by a microdilution method. All the novel derivatives exerted potent or moderate active against M. tuberculosis H37Rv, with MIC values ranging from 4 to 64 μg/mL. The most potent derivative 3m showed an identical MIC value of 4 μg/mL for both M. tuberculosis H37Rv and rifampin-resistant M. tuberculosis 261. It demonstrated no inhibitory effects against six different tumor cell lines by a MTT assay and had a good safety profile in a vero cell line, providing a good lead for subsequent optimization in search of novel affordable antitubercular agents.
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Affiliation(s)
- Wei Ang
- Key Laboratory of Drug Targeting and Drug Delivery System of the Education Ministry, Department of Medicinal Chemistry, West China School of Pharmacy, Sichuan University, Chengdu 610041, Sichuan, China
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, Sichuan, China
| | - Yan-Ni Lin
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, Sichuan, China
| | - Tao Yang
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, Sichuan, China
| | - Jian-Zhong Yang
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, Sichuan, China
| | - Wei-Yi Pi
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, Sichuan, China
| | - Ying-Hong Yang
- Department of Pharmaceutical and Bioengineering, School of Chemical Engineering, Sichuan University, Chengdu 610065, Sichuan, China
| | - You-Fu Luo
- Authors to whom correspondence should be addressed; (Y.-F.L.); (Y.D.); Tel.: +86-28-8550-3817 (Y.-F.L.); Fax: +86-28-8550-3817 (Y.-F.L.); Tel.: +86-28-8550-3790 (Y.D.); Fax: +86-28-8550-3790 (Y.D.)
| | - Yong Deng
- Key Laboratory of Drug Targeting and Drug Delivery System of the Education Ministry, Department of Medicinal Chemistry, West China School of Pharmacy, Sichuan University, Chengdu 610041, Sichuan, China
- Authors to whom correspondence should be addressed; (Y.-F.L.); (Y.D.); Tel.: +86-28-8550-3817 (Y.-F.L.); Fax: +86-28-8550-3817 (Y.-F.L.); Tel.: +86-28-8550-3790 (Y.D.); Fax: +86-28-8550-3790 (Y.D.)
| | - Yu-Quan Wei
- State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, Sichuan, China
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Novel N-benzoyl-2-hydroxybenzamide disrupts unique parasite secretory pathway. Antimicrob Agents Chemother 2012; 56:2666-82. [PMID: 22354304 DOI: 10.1128/aac.06450-11] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Toxoplasma gondii is a protozoan parasite that can damage the human brain and eyes. There are no curative medicines. Herein, we describe our discovery of N-benzoyl-2-hydroxybenzamides as a class of compounds effective in the low nanomolar range against T. gondii in vitro and in vivo. Our lead compound, QQ-437, displays robust activity against the parasite and could be useful as a new scaffold for development of novel and improved inhibitors of T. gondii. Our genome-wide investigations reveal a specific mechanism of resistance to N-benzoyl-2-hydroxybenzamides mediated by adaptin-3β, a large protein from the secretory protein complex. N-Benzoyl-2-hydroxybenzamide-resistant clones have alterations of their secretory pathway, which traffics proteins to micronemes, rhoptries, dense granules, and acidocalcisomes/plant-like vacuole (PLVs). N-Benzoyl-2-hydroxybenzamide treatment also alters micronemes, rhoptries, the contents of dense granules, and, most markedly, acidocalcisomes/PLVs. Furthermore, QQ-437 is active against chloroquine-resistant Plasmodium falciparum. Our studies reveal a novel class of compounds that disrupts a unique secretory pathway of T. gondii, with the potential to be used as scaffolds in the search for improved compounds to treat the devastating diseases caused by apicomplexan parasites.
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Platon M, Cui L, Mom S, Richard P, Saeys M, Hierso JC. Etherification of Functionalized Phenols with Chloroheteroarenes at Low Palladium Loading: Theoretical Assessment of the Role of Triphosphane Ligands in CO Reductive Elimination. Adv Synth Catal 2011. [DOI: 10.1002/adsc.201100481] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Lu X, Huang K, You Q. Enoyl acyl carrier protein reductase inhibitors: a patent review (2006 - 2010). Expert Opin Ther Pat 2011; 21:1007-22. [PMID: 21651455 DOI: 10.1517/13543776.2011.581227] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
INTRODUCTION Bacterial enoyl acyl carrier protein reductase (ENR) specificity reduces the double bond in enoyl thioester substrates in the final enzymatic step of the elongation cycle of the fatty acid synthase-II pathway. Its function is essential for bacterial organism survival, making it an attractive target for the development of novel antibiotics. The structural features and therapeutic potential of this enzyme have stimulated the rational design of ENR inhibitors, and important progress has been achieved to date. AREAS COVERED This review describes recent advances made in the search for ENR inhibitors, as reflected by patent applications filed from 2006 to 2010, together with an overview of the relevant literature. The first section of this paper provides a background of the biology of ENR, followed by a description of its structure and function. The main section describes the substrate specificities for ENR, and the structure-based rational design of patent inhibitors originating from different companies and academic groups. EXPERT OPINION The increase in the number of ENR inhibitors bodes well for the development of new therapeutics against multidrug-resistant bacteria. The challenge is now to improve the pharmacokinetic parameters of these inhibitors and translate them into clinical studies.
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Affiliation(s)
- Xiaoyun Lu
- Guangzhou Institutes of Biomedicine and Health, Key Laboratory of Regenerative Biology and Institute of Chemical Biology, Chinese Academy of Sciences, No. 190, Kaiyuan Avenue, Science Park, Guangzhou, 510530, China
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Maffeo D, Velkov Z, Misiakos K, Mergia K, Paulidou A, Zavali M, Mavridis IM, Yannakopoulou K. Real-time monitoring of nanomolar binding to a cyclodextrin monolayer immobilized on a Si/SiO2/novolac surface using white light reflectance spectroscopy: The case of triclosan. J Colloid Interface Sci 2011; 358:369-75. [DOI: 10.1016/j.jcis.2011.03.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Revised: 03/08/2011] [Accepted: 03/08/2011] [Indexed: 10/18/2022]
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An efficient fluoride-mediated O-arylation of sterically hindered halophenols with silylaryl triflates under mild reaction conditions. Tetrahedron Lett 2011. [DOI: 10.1016/j.tetlet.2011.03.124] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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