1
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Jamabo M, Mahlalela M, Edkins AL, Boshoff A. Tackling Sleeping Sickness: Current and Promising Therapeutics and Treatment Strategies. Int J Mol Sci 2023; 24:12529. [PMID: 37569903 PMCID: PMC10420020 DOI: 10.3390/ijms241512529] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 07/27/2023] [Accepted: 08/03/2023] [Indexed: 08/13/2023] Open
Abstract
Human African trypanosomiasis is a neglected tropical disease caused by the extracellular protozoan parasite Trypanosoma brucei, and targeted for eradication by 2030. The COVID-19 pandemic contributed to the lengthening of the proposed time frame for eliminating human African trypanosomiasis as control programs were interrupted. Armed with extensive antigenic variation and the depletion of the B cell population during an infectious cycle, attempts to develop a vaccine have remained unachievable. With the absence of a vaccine, control of the disease has relied heavily on intensive screening measures and the use of drugs. The chemotherapeutics previously available for disease management were plagued by issues such as toxicity, resistance, and difficulty in administration. The approval of the latest and first oral drug, fexinidazole, is a major chemotherapeutic achievement for the treatment of human African trypanosomiasis in the past few decades. Timely and accurate diagnosis is essential for effective treatment, while poor compliance and resistance remain outstanding challenges. Drug discovery is on-going, and herein we review the recent advances in anti-trypanosomal drug discovery, including novel potential drug targets. The numerous challenges associated with disease eradication will also be addressed.
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Affiliation(s)
- Miebaka Jamabo
- Biotechnology Innovation Centre, Rhodes University, Makhanda 6139, South Africa; (M.J.); (M.M.)
| | - Maduma Mahlalela
- Biotechnology Innovation Centre, Rhodes University, Makhanda 6139, South Africa; (M.J.); (M.M.)
| | - Adrienne L. Edkins
- Department of Biochemistry and Microbiology, Biomedical Biotechnology Research Centre (BioBRU), Rhodes University, Makhanda 6139, South Africa;
| | - Aileen Boshoff
- Biotechnology Innovation Centre, Rhodes University, Makhanda 6139, South Africa; (M.J.); (M.M.)
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2
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Asymmetric preparation of 2,4,
6‐trisubstituted
dihydropyridazinones. B KOREAN CHEM SOC 2022. [DOI: 10.1002/bkcs.12630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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3
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Zheng Y, Müller J, Kunz S, Siderius M, Maes L, Caljon G, Müller N, Hemphill A, Sterk GJ, Leurs R. 3-nitroimidazo[1,2-b]pyridazine as a novel scaffold for antiparasitics with sub-nanomolar anti-Giardia lamblia activity. Int J Parasitol Drugs Drug Resist 2022; 19:47-55. [PMID: 35716585 PMCID: PMC9213561 DOI: 10.1016/j.ijpddr.2022.05.004] [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: 01/15/2022] [Revised: 05/18/2022] [Accepted: 05/20/2022] [Indexed: 11/26/2022]
Abstract
As there is a continuous need for novel anti-infectives, the present study aimed to fuse two modes of action into a novel 3-nitroimidazo[1,2-b]pyridazine scaffold to improve antiparasitic efficacy. For this purpose, we combined known structural elements of phosphodiesterase inhibitors, a target recently proposed for Trypanosoma brucei and Giardia lamblia, with a nitroimidazole scaffold to generate nitrosative stress. The compounds were evaluated in vitro against a panel of protozoal parasites, namely Giardia lamblia, Trypanosoma brucei, T. cruzi, Leishmania infantum and Plasmodium falciparum and for cytotoxicity on MRC-5 cells. Interestingly, selective sub-nanomolar activity was obtained against G. lamblia, and by testing several analogues with and without the nitro group, it was shown that the presence of a nitro group, but not PDE inhibition, is responsible for the low IC50 values of these novel compounds. Adding the favourable drug-like properties (low molecular weight, cLogP (1.2–4.1) and low polar surface area), the key compounds from the 3-nitroimidazo[1,2-b]pyridazine series can be considered as valuable hits for further anti-giardiasis drug exploration and development. Analogues fusing a nitroimidazole moiety and a PDE inhibitor scaffold were prepared. These compounds were tested in vitro against a panel of protozoal parasites. Against Giardia lamblia, sub-nanomolar IC50 values were determined. PDE inhibition provided no significant contribution to the anti-Giardia potency. High potency with drug-like properties warrants further study of this hit series.
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4
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Llanos MA, Alberca LN, Larrea SCV, Schoijet AC, Alonso GD, Bellera CL, Gavenet L, Talevi A. Homology Modeling and Molecular Dynamics Simulations of Trypanosoma cruzi Phosphodiesterase b1. Chem Biodivers 2021; 19:e202100712. [PMID: 34813143 DOI: 10.1002/cbdv.202100712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 11/22/2021] [Indexed: 11/07/2022]
Abstract
Cyclic nucleotide phosphodiesterases have been implicated in the proliferation, differentiation and osmotic regulation of trypanosomatids; in some trypanosomatid species, they have been validated as molecular targets for the development of new therapeutic agents. Because the experimental structure of Trypanosoma cruzi PDEb1 (TcrPDEb1) has not been solved so far, an homology model of the target was created using the structure of Trypanosoma brucei PDEb1 (TbrPDEb1) as a template. The model was refined by extensive enhanced sampling molecular dynamics simulations, and representative snapshots were extracted from the trajectory by combined clustering analysis. This structural ensemble was used to develop a structure-based docking model of the target. The docking accuracy of the model was validated by redocking and cross-docking experiments using all available crystal structures of TbrPDEb1, whereas the scoring accuracy was validated through a retrospective screen, using a carefully curated dataset of compounds assayed against TbrPDEb1 and/or TcrPDEb1. Considering the results from in silico validations, the model may be applied in prospective virtual screening campaigns to identify novel hits, as well as to guide the rational design of potent and selective inhibitors targeting this enzyme.
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Affiliation(s)
- Manuel A Llanos
- Laboratory of Bioactive Research and Development (LIDeB), Faculty of Exact Sciences, University of La Plata - 47 and 115, La Plata, Buenos Aires, Argentina
| | - Lucas N Alberca
- Laboratory of Bioactive Research and Development (LIDeB), Faculty of Exact Sciences, University of La Plata - 47 and 115, La Plata, Buenos Aires, Argentina
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI-CONICET), Buenos Aires, Argentina
| | - Salomé C Vilchez Larrea
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI-CONICET), Buenos Aires, Argentina
| | - Alejandra C Schoijet
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI-CONICET), Buenos Aires, Argentina
| | - Guillermo D Alonso
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI-CONICET), Buenos Aires, Argentina
| | - Carolina L Bellera
- Laboratory of Bioactive Research and Development (LIDeB), Faculty of Exact Sciences, University of La Plata - 47 and 115, La Plata, Buenos Aires, Argentina
- National Scientific and Technical Research Council (CONICET) - CCT, La Plata, Argentina
| | - Luciana Gavenet
- Laboratory of Bioactive Research and Development (LIDeB), Faculty of Exact Sciences, University of La Plata - 47 and 115, La Plata, Buenos Aires, Argentina
- National Scientific and Technical Research Council (CONICET) - CCT, La Plata, Argentina
| | - Alan Talevi
- Laboratory of Bioactive Research and Development (LIDeB), Faculty of Exact Sciences, University of La Plata - 47 and 115, La Plata, Buenos Aires, Argentina
- National Scientific and Technical Research Council (CONICET) - CCT, La Plata, Argentina
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5
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De Araújo JS, da Silva PB, Batista MM, Peres RB, Cardoso-Santos C, Kalejaiye TD, Munday JC, De Heuvel E, Sterk GJ, Augustyns K, Salado IG, Matheeussen A, De Esch I, De Koning HP, Leurs R, Maes L, Soeiro MDNC. Evaluation of phthalazinone phosphodiesterase inhibitors with improved activity and selectivity against Trypanosoma cruzi. J Antimicrob Chemother 2021; 75:958-967. [PMID: 31860098 DOI: 10.1093/jac/dkz516] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 10/15/2019] [Accepted: 11/08/2019] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Chagas' disease, caused by the protozoan parasite Trypanosoma cruzi, needs urgent alternative therapeutic options as the treatments currently available display severe limitations, mainly related to efficacy and toxicity. OBJECTIVES As phosphodiesterases (PDEs) have been claimed as novel targets against T. cruzi, our aim was to evaluate the biological aspects of 12 new phthalazinone PDE inhibitors against different T. cruzi strains and parasite forms relevant for human infection. METHODS In vitro trypanocidal activity of the inhibitors was assessed alone and in combination with benznidazole. Their effects on parasite ultrastructural and cAMP levels were determined. PDE mRNA levels from the different T. cruzi forms were measured by quantitative reverse transcription PCR. RESULTS Five TcrPDEs were found to be expressed in all parasite stages. Four compounds displayed strong effects against intracellular amastigotes. Against bloodstream trypomastigotes (BTs), three were at least as potent as benznidazole. In vitro combination therapy with one of the most active inhibitors on both parasite forms (NPD-040) plus benznidazole demonstrated a quite synergistic profile (xΣ FICI = 0.58) against intracellular amastigotes but no interaction (xΣ FICI = 1.27) when BTs were assayed. BTs treated with NPD-040 presented disrupted Golgi apparatus, a swollen flagellar pocket and signs of autophagy. cAMP measurements of untreated parasites showed that amastigotes have higher ability to efflux this second messenger than BTs. NPD-001 and NPD-040 increase the intracellular cAMP content in both BTs and amastigotes, which is also released into the extracellular milieu. CONCLUSIONS The findings demonstrate the potential of PDE inhibitors as anti-T. cruzi drug candidates.
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Affiliation(s)
| | | | - Marcos Meuser Batista
- Laboratório de Biologia Celular, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Raiza Brandão Peres
- Laboratório de Biologia Celular, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Camila Cardoso-Santos
- Laboratório de Biologia Celular, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Titilola D Kalejaiye
- Institute of Infection, Immunity & Inflammation, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK
| | - Jane C Munday
- Institute of Infection, Immunity & Inflammation, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK
| | - Erik De Heuvel
- Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines & Systems, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Geert Jan Sterk
- Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines & Systems, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Koen Augustyns
- Laboratory of Medicinal Chemistry, University of Antwerp, Antwerp, Belgium
| | - Irene G Salado
- Laboratory of Medicinal Chemistry, University of Antwerp, Antwerp, Belgium
| | - An Matheeussen
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Antwerp, Belgium
| | - Iwan De Esch
- Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines & Systems, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Harry P De Koning
- Institute of Infection, Immunity & Inflammation, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK
| | - Rob Leurs
- Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines & Systems, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Louis Maes
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Antwerp, Belgium
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6
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Wijtmans M, Edink E, van Linden OP, Zheng Y, Blaazer AR, Siderius M, van Muijlwijk-Koezen JE. From recipe to research: introducing undergraduate students to the nature of science using a hybrid practical course centred on drug discovery for neglected diseases. Drug Discov Today 2021; 26:1359-1368. [PMID: 33609778 DOI: 10.1016/j.drudis.2021.02.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 01/23/2021] [Accepted: 02/11/2021] [Indexed: 10/22/2022]
Abstract
A hybrid undergraduate practical course involving synthetic medicinal chemistry on neglected diseases bridges the gap between skills, techniques and scientific research, and exposes students to the nature of science.
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Affiliation(s)
- Maikel Wijtmans
- Division of Medicinal Chemistry, Amsterdam Institute of Molecular and Life Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands; Division of Innovations in Human Health and Life Sciences, Amsterdam Institute of Molecular and Life Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
| | - Ewald Edink
- Division of Medicinal Chemistry, Amsterdam Institute of Molecular and Life Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands; Current address: Department of Life Sciences and Chemistry, Faculty of Agri, Food and Life Sciences, Inholland University of Applied Sciences, De Boelelaan 1109, 1081 HV Amsterdam, The Netherlands
| | - Oscar Pj van Linden
- Division of Innovations in Human Health and Life Sciences, Amsterdam Institute of Molecular and Life Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
| | - Yang Zheng
- Division of Medicinal Chemistry, Amsterdam Institute of Molecular and Life Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
| | - Antoni R Blaazer
- Division of Innovations in Human Health and Life Sciences, Amsterdam Institute of Molecular and Life Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
| | - Marco Siderius
- Division of Medicinal Chemistry, Amsterdam Institute of Molecular and Life Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
| | - Jacqueline E van Muijlwijk-Koezen
- Division of Innovations in Human Health and Life Sciences, Amsterdam Institute of Molecular and Life Sciences, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands.
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7
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Tetrahydrophthalazinone Inhibitor of Phosphodiesterase with In Vitro Activity against Intracellular Trypanosomatids. Antimicrob Agents Chemother 2021; 65:AAC.00960-20. [PMID: 33361300 DOI: 10.1128/aac.00960-20] [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: 05/11/2020] [Accepted: 12/16/2020] [Indexed: 11/20/2022] Open
Abstract
The phosphodiesterase inhibitor tetrahydrophthalazinone NPD-008 was explored by phenotypic in vitro screening, target validation, and ultrastructural approaches against Trypanosoma cruzi NPD-008 displayed activity against different forms and strains of T. cruzi (50% effective concentration [EC50], 6.6 to 39.5 μM). NPD-008 increased cAMP levels of T. cruzi and its combination with benznidazole gave synergistic interaction. It was also moderately active against intracellular amastigotes of Leishmania amazonensis and Leishmania infantum, confirming a potential activity profile as an antitrypanosomatid drug candidate.
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8
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de Heuvel E, Kooistra AJ, Edink E, van Klaveren S, Stuijt J, van der Meer T, Sadek P, Mabille D, Caljon G, Maes L, Siderius M, de Esch IJP, Sterk GJ, Leurs R. Discovery of Diaryl Ether Substituted Tetrahydrophthalazinones as TbrPDEB1 Inhibitors Following Structure-Based Virtual Screening. Front Chem 2021; 8:608030. [PMID: 33553105 PMCID: PMC7859335 DOI: 10.3389/fchem.2020.608030] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 12/16/2020] [Indexed: 12/04/2022] Open
Abstract
Several members of the 3′,5′-cyclic nucleotide phosphodiesterase (PDE) family play an essential role in cellular processes, which has labeled them as interesting targets for various diseases. The parasitic protozoan Trypanosoma brucei, causative agent of human African trypanosomiasis, contains several cyclic AMP specific PDEs from which TbrPDEB1 is validated as a drug target. The recent discovery of selective TbrPDEB1 inhibitors has increased their potential for a novel treatment for this disease. Compounds characterized by a rigid biphenyl tetrahydrophthalazinone core structure were used as starting point for the exploration of novel TbrPDEB1 inhibitors. Using a virtual screening campaign and structure-guided design, diaryl ether substituted phthalazinones were identified as novel TbrPDEB1 inhibitors with IC50 values around 1 μM against T. brucei. This study provides important structure-activity relationship (SAR) information for the future design of effective parasite-specific PDE inhibitors.
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Affiliation(s)
- Erik de Heuvel
- Division of Medicinal Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Albert J Kooistra
- Division of Medicinal Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Ewald Edink
- Division of Medicinal Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Sjors van Klaveren
- Division of Medicinal Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Jeffrey Stuijt
- Division of Medicinal Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Tiffany van der Meer
- Division of Medicinal Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Payman Sadek
- Division of Medicinal Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Dorien Mabille
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium
| | - Guy Caljon
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium
| | - Louis Maes
- Laboratory of Microbiology, Parasitology and Hygiene, University of Antwerp, Wilrijk, Belgium
| | - Marco Siderius
- Division of Medicinal Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Iwan J P de Esch
- Division of Medicinal Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Geert Jan Sterk
- Division of Medicinal Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Rob Leurs
- Division of Medicinal Chemistry, Amsterdam Institute of Molecular and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
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9
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Talukdar R. Synthetically Important Ring-Opening Acylations of Alkoxybenzenes. SYNTHESIS-STUTTGART 2020. [DOI: 10.1055/s-0040-1707255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
AbstractCyclic ketones, anhydrides, lactams and lactones are a particular class of molecules that are often used in synthesis, wherein their electrophilic properties are leveraged to enable facile Friedel–Crafts ring openings through nucleophilic attack at the carbonyl sp2 centre. The use of electron-rich alkoxybenzenes as nucleophiles has also become important since the discovery of the Friedel–Crafts reaction. As a result, various isomeric alkoxybenzenes are used for preparing starting materials in target-oriented syntheses. This review covers the instances of different alkoxybenzenes that are used as nucleophiles in ring-opening acylations with carbonyl-containing cyclic electrophiles, for the construction of important building blocks for multistep transformations. This review summarizes the ring-opening functionalization of three- to seven-membered molecular rings with alkoxybenzenes in a Friedel–Crafts fashion. Sometimes the rings need subtle or considerable activation by the help of Lewis acid(s), followed by nucleophilic attack. This review is aimed to be a summary of the important acylations of electron-rich alkoxybenzenes by nucleophilic ring-opening of cyclic molecules. The works cited employ a wide range of conditions and differently substituted substrates for target-oriented syntheses.1 Introduction and Scope2 Arenes for Acylative Ring Opening2.1 Three-Membered Rings: Ring Opening of Oxirane-2,3-dione2.2 Four-Membered Rings2.2.1 Ring Opening of Cyclobutanones2.2.2 Ring Opening of β-Lactams2.2.3 Ring Opening of β-Lactone2.3 Five-Membered Rings2.3.1 Ring Opening of Phthalimides2.3.2 Ring Opening of γ-Lactones2.3.3 Ring Opening of Anhydrides2.4 Six-Membered Rings2.5 Seven-Membered Rings3 Conclusion
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10
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Munday JC, Kunz S, Kalejaiye TD, Siderius M, Schroeder S, Paape D, Alghamdi AH, Abbasi Z, Huang SX, Donachie AM, William S, Sabra AN, Sterk GJ, Botros SS, Brown DG, Hoffman CS, Leurs R, de Koning HP. Cloning and functional complementation of ten Schistosoma mansoni phosphodiesterases expressed in the mammalian host stages. PLoS Negl Trop Dis 2020; 14:e0008447. [PMID: 32730343 PMCID: PMC7430754 DOI: 10.1371/journal.pntd.0008447] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 08/17/2020] [Accepted: 06/02/2020] [Indexed: 01/29/2023] Open
Abstract
Only a single drug against schistosomiasis is currently available and new drug development is urgently required but very few drug targets have been validated and characterised. However, regulatory systems including cyclic nucleotide metabolism are emerging as primary candidates for drug discovery. Here, we report the cloning of ten cyclic nucleotide phosphodiesterase (PDE) genes of S. mansoni, out of a total of 11 identified in its genome. We classify these PDEs by homology to human PDEs. Male worms displayed higher expression levels for all PDEs, in mature and juvenile worms, and schistosomula. Several functional complementation approaches were used to characterise these genes. We constructed a Trypanosoma brucei cell line in which expression of a cAMP-degrading PDE complements the deletion of TbrPDEB1/B2. Inhibitor screens of these cells expressing only either SmPDE4A, TbrPDEB1 or TbrPDEB2, identified highly potent inhibitors of the S. mansoni enzyme that elevated the cellular cAMP concentration. We further expressed most of the cloned SmPDEs in two pde1Δ/pde2Δ strains of Saccharomyces cerevisiae and some also in a specialised strain of Schizosacharomyces pombe. Five PDEs, SmPDE1, SmPDE4A, SmPDE8, SmPDE9A and SmPDE11 successfully complemented the S. cerevisiae strains, and SmPDE7var also complemented to a lesser degree, in liquid culture. SmPDE4A, SmPDE8 and SmPDE11 were further assessed in S. pombe for hydrolysis of cAMP and cGMP; SmPDE11 displayed considerable preferrence for cGMP over cAMP. These results and tools enable the pursuit of a rigorous drug discovery program based on inhibitors of S. mansoni PDEs.
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Affiliation(s)
- Jane C. Munday
- Institute of Infection, Immunity and inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, United Kingdom
| | - Stefan Kunz
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems, Vrije Universiteit Amsterdam, The Netherlands
| | - Titilola D. Kalejaiye
- Institute of Infection, Immunity and inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, United Kingdom
| | - Marco Siderius
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems, Vrije Universiteit Amsterdam, The Netherlands
| | | | - Daniel Paape
- Institute of Infection, Immunity and inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, United Kingdom
| | - Ali H. Alghamdi
- Institute of Infection, Immunity and inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, United Kingdom
| | - Zainab Abbasi
- Biology Department, Boston College, Chestnut Hill, Massachusetts, United States of America
| | - Sheng Xiang Huang
- Biology Department, Boston College, Chestnut Hill, Massachusetts, United States of America
| | - Anne-Marie Donachie
- Institute of Infection, Immunity and inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, United Kingdom
| | - Samia William
- Department of Pharmacology, Theodor Bilharz Research Institute, Warrak El-Hadar, Imbaba, Egypt
| | - Abdel Nasser Sabra
- Department of Pharmacology, Theodor Bilharz Research Institute, Warrak El-Hadar, Imbaba, Egypt
| | - Geert Jan Sterk
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems, Vrije Universiteit Amsterdam, The Netherlands
| | - Sanaa S. Botros
- Department of Pharmacology, Theodor Bilharz Research Institute, Warrak El-Hadar, Imbaba, Egypt
| | - David G. Brown
- School of Biosciences, University of Kent, United Kingdom
| | - Charles S. Hoffman
- Biology Department, Boston College, Chestnut Hill, Massachusetts, United States of America
| | - Rob Leurs
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems, Vrije Universiteit Amsterdam, The Netherlands
| | - Harry P. de Koning
- Institute of Infection, Immunity and inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, United Kingdom
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11
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Salado IG, Singh AK, Moreno-Cinos C, Sakaine G, Siderius M, Van der Veken P, Matheeussen A, van der Meer T, Sadek P, Gul S, Maes L, Sterk GJ, Leurs R, Brown D, Augustyns K. Lead Optimization of Phthalazinone Phosphodiesterase Inhibitors as Novel Antitrypanosomal Compounds. J Med Chem 2020; 63:3485-3507. [PMID: 32196340 DOI: 10.1021/acs.jmedchem.9b00985] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Human African trypanosomiasis is causing thousands of deaths every year in the rural areas of Africa. In this manuscript we describe the optimization of a family of phtalazinone derivatives. Phosphodiesterases have emerged as attractive molecular targets for a novel treatment for a variety of neglected parasitic diseases. Compound 1 resulted in being a potent TbrPDEB1 inhibitor with interesting activity against T. brucei in a phenotypic screen. Derivative 1 was studied in an acute in vivo mouse disease model but unfortunately showed no efficacy due to low metabolic stability. We report structural modifications to achieve compounds with an improved metabolic stability while maintaining high potency against TbrPDEB1 and T. brucei. Compound 14 presented a good microsomal stability in mouse and human microsomes and provides a good starting point for future efforts.
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Affiliation(s)
- Irene G Salado
- Laboratory of Medicinal Chemistry, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Abhimanyu K Singh
- School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, United Kingdom
| | - Carlos Moreno-Cinos
- Laboratory of Medicinal Chemistry, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Guna Sakaine
- Laboratory of Medicinal Chemistry, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Marco Siderius
- Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines & Systems, Faculty of Science, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands
| | - Pieter Van der Veken
- Laboratory of Medicinal Chemistry, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - An Matheeussen
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Tiffany van der Meer
- Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines & Systems, Faculty of Science, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands
| | - Payman Sadek
- Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines & Systems, Faculty of Science, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands
| | - Sheraz Gul
- Fraunhofer-IME SP, Schnackenburgallee 114, Hamburg 22525, Germany
| | - Louis Maes
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Geert-Jan Sterk
- Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines & Systems, Faculty of Science, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands
| | - Rob Leurs
- Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines & Systems, Faculty of Science, Vrije Universiteit Amsterdam, 1081 Amsterdam, The Netherlands
| | - David Brown
- School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, United Kingdom
| | - Koen Augustyns
- Laboratory of Medicinal Chemistry, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
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12
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de Heuvel E, Singh AK, Boronat P, Kooistra AJ, van der Meer T, Sadek P, Blaazer AR, Shaner NC, Bindels DS, Caljon G, Maes L, Sterk GJ, Siderius M, Oberholzer M, de Esch IJ, Brown DG, Leurs R. Alkynamide phthalazinones as a new class of TbrPDEB1 inhibitors (Part 2). Bioorg Med Chem 2019; 27:4013-4029. [DOI: 10.1016/j.bmc.2019.06.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Revised: 06/12/2019] [Accepted: 06/14/2019] [Indexed: 01/27/2023]
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13
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Discovery of novel Schistosoma mansoni PDE4A inhibitors as potential agents against schistosomiasis. Future Med Chem 2019; 11:1703-1720. [PMID: 31370708 DOI: 10.4155/fmc-2018-0592] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Aim: Due to the urgent need for effective drugs to treat schistosomiasis that act through a known molecular mechanism of action, we focused on a target-based approach with the aim to discover inhibitors of a cyclic nucleotide phosphodiesterase from Schistosoma mansoni (SmPDE4A). Materials & methods: To discover new inhibitors of SmPDE4A homology models of the enzyme structure were constructed based on known human and protozoan homologs. The best two models were selected for subsequent virtual screening of our in-house chemical library. Results & conclusion: A total of 25 library compounds were selected for experimental confirmation as SmPDE4A inhibitors and after dose-response experiments, three top hits were identified. The results presented validate the virtual screening approach to identify new inhibitors for clinically relevant phosphodiesterases.
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14
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Alkynamide phthalazinones as a new class of TbrPDEB1 inhibitors. Bioorg Med Chem 2019; 27:3998-4012. [PMID: 31327675 DOI: 10.1016/j.bmc.2019.06.027] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 11/21/2018] [Accepted: 06/14/2019] [Indexed: 12/26/2022]
Abstract
Several 3',5'-cyclic nucleotide phosphodiesterases (PDEs) have been validated as good drug targets for a large variety of diseases. Trypanosoma brucei PDEB1 (TbrPDEB1) has been designated as a promising drug target for the treatment of human African trypanosomiasis. Recently, the first class of selective nanomolar TbrPDEB1 inhibitors was obtained by targeting the parasite specific P-pocket. However, these biphenyl-substituted tetrahydrophthalazinone-based inhibitors did not show potent cellular activity against Trypanosoma brucei (T. brucei) parasites, leaving room for further optimization. Herein, we report the discovery of a new class of potent TbrPDEB1 inhibitors that display improved activities against T. brucei parasites. Exploring different linkers between the reported tetrahydrophthalazinone core scaffold and the amide tail group resulted in the discovery of alkynamide phthalazinones as new TbrPDEB1 inhibitors, which exhibit submicromolar activities versus T. brucei parasites and no cytotoxicity to human MRC-5 cells. Elucidation of the crystal structure of alkynamide 8b (NPD-048) bound to the catalytic domain of TbrPDEB1 shows a bidentate interaction with the key-residue Gln874 and good directionality towards the P-pocket. Incubation of trypanosomes with alkynamide 8b results in an increase of intracellular cAMP, validating a PDE-mediated effect in vitro and providing a new interesting compound series for further studies towards selective TbrPDEB1 inhibitors with potent phenotypic activity.
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15
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Botros SS, William S, Sabra ANA, El-Lakkany NM, Seif El-Din SH, García-Rubia A, Sebastián-Pérez V, Blaazer AR, de Heuvel E, Sijm M, Zheng Y, Salado IG, Munday JC, Maes L, de Esch IJP, Sterk GJ, Augustyns K, Leurs R, Gil C, De Koning HP. Screening of a PDE-focused library identifies imidazoles with in vitro and in vivo antischistosomal activity. Int J Parasitol Drugs Drug Resist 2019; 9:35-43. [PMID: 30669086 PMCID: PMC6350229 DOI: 10.1016/j.ijpddr.2019.01.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 01/10/2019] [Accepted: 01/13/2019] [Indexed: 01/10/2023]
Abstract
We report the evaluation of 265 compounds from a PDE-focused library for their antischistosomal activity, assessed in vitro using Schistosoma mansoni. Of the tested compounds, 171 (64%) displayed selective in vitro activity, with 16 causing worm hypermotility/spastic contractions and 41 inducing various degrees of worm killing at 100 μM, with the surviving worms displaying sluggish movement, worm unpairing and complete absence of eggs. The compounds that did not affect worm viability (n = 72) induced a complete cessation of ovipositing. 82% of the compounds had an impact on male worms whereas female worms were barely affected. In vivo evaluation in S. mansoni-infected mice with the in vitro 'hit' NPD-0274 at 20 mg/kg/day orally for 5 days resulted in worm burden reductions of 29% and intestinal tissue egg load reduction of 35% at 10 days post-treatment. Combination of praziquantel (PZQ) at 10 mg/kg/day for 5 days with NPD-0274 or NPD-0298 resulted in significantly higher worm killing than PZQ alone, as well as a reduction in intestinal tissue egg load, disappearance of immature eggs and an increase in the number of dead eggs.
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Affiliation(s)
- Sanaa S Botros
- Pharmacology Department, Theodor Bilharz Research Institute, Warrak El-Hadar, Imbaba, P.O. Box 30, Giza, 12411, Egypt
| | - Samia William
- Parasitology Department, Theodor Bilharz Research Institute, Warrak El-Hadar, Imbaba, P.O. Box 30, Giza, 12411, Egypt
| | - Abdel-Nasser A Sabra
- Pharmacology Department, Theodor Bilharz Research Institute, Warrak El-Hadar, Imbaba, P.O. Box 30, Giza, 12411, Egypt
| | - Naglaa M El-Lakkany
- Pharmacology Department, Theodor Bilharz Research Institute, Warrak El-Hadar, Imbaba, P.O. Box 30, Giza, 12411, Egypt
| | - Sayed H Seif El-Din
- Pharmacology Department, Theodor Bilharz Research Institute, Warrak El-Hadar, Imbaba, P.O. Box 30, Giza, 12411, Egypt
| | | | | | - Antoni R Blaazer
- Medicinal Chemistry Vrije Universiteit Amsterdam (VUA), the Netherlands
| | - Erik de Heuvel
- Medicinal Chemistry Vrije Universiteit Amsterdam (VUA), the Netherlands
| | - Maarten Sijm
- Medicinal Chemistry Vrije Universiteit Amsterdam (VUA), the Netherlands
| | - Yang Zheng
- Medicinal Chemistry Vrije Universiteit Amsterdam (VUA), the Netherlands
| | | | - Jane C Munday
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, G12 8TA, UK
| | | | - Iwan J P de Esch
- Medicinal Chemistry Vrije Universiteit Amsterdam (VUA), the Netherlands
| | - Geert J Sterk
- Medicinal Chemistry Vrije Universiteit Amsterdam (VUA), the Netherlands
| | | | - Rob Leurs
- Medicinal Chemistry Vrije Universiteit Amsterdam (VUA), the Netherlands
| | - Carmen Gil
- Centro de Investigaciones Biológicas (CIB-CSIC), Madrid, Spain
| | - Harry P De Koning
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, G12 8TA, UK.
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16
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Nucleoside analogue activators of cyclic AMP-independent protein kinase A of Trypanosoma. Nat Commun 2019; 10:1421. [PMID: 30926779 PMCID: PMC6440977 DOI: 10.1038/s41467-019-09338-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Accepted: 03/07/2019] [Indexed: 02/08/2023] Open
Abstract
Protein kinase A (PKA), the main effector of cAMP in eukaryotes, is a paradigm for the mechanisms of ligand-dependent and allosteric regulation in signalling. Here we report the orthologous but cAMP-independent PKA of the protozoan Trypanosoma and identify 7-deaza-nucleosides as potent activators (EC50 ≥ 6.5 nM) and high affinity ligands (KD ≥ 8 nM). A co-crystal structure of trypanosome PKA with 7-cyano-7-deazainosine and molecular docking show how substitution of key amino acids in both CNB domains of the regulatory subunit and its unique C-terminal αD helix account for this ligand swap between trypanosome PKA and canonical cAMP-dependent PKAs. We propose nucleoside-related endogenous activators of Trypanosoma brucei PKA (TbPKA). The existence of eukaryotic CNB domains not associated with binding of cyclic nucleotides suggests that orphan CNB domains in other eukaryotes may bind undiscovered signalling molecules. Phosphoproteome analysis validates 7-cyano-7-deazainosine as powerful cell-permeable inducer to explore cAMP-independent PKA signalling in medically important neglected pathogens.
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17
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Shaw S, DeMarco SF, Rehmann R, Wenzler T, Florini F, Roditi I, Hill KL. Flagellar cAMP signaling controls trypanosome progression through host tissues. Nat Commun 2019; 10:803. [PMID: 30778051 PMCID: PMC6379439 DOI: 10.1038/s41467-019-08696-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 01/18/2019] [Indexed: 02/07/2023] Open
Abstract
The unicellular parasite Trypanosoma brucei is transmitted between mammals by tsetse flies. Following the discovery that flagellar phosphodiesterase PDEB1 is required for trypanosomes to move in response to signals in vitro (social motility), we investigated its role in tsetse flies. Here we show that PDEB1 knockout parasites exhibit subtle changes in movement, reminiscent of bacterial chemotaxis mutants. Infecting flies with the knockout, followed by live confocal microscopy of fluorescent parasites within dual-labelled insect tissues, shows that PDEB1 is important for traversal of the peritrophic matrix, which separates the midgut lumen from the ectoperitrophic space. Without PDEB1, parasites are trapped in the lumen and cannot progress through the cycle. This demonstrates that the peritrophic matrix is a barrier that must be actively overcome and that the parasite’s flagellar cAMP signaling pathway facilitates this. Migration may depend on perception of chemotactic cues, which could stem from co-infecting parasites and/or the insect host. Trypanosoma brucei probably relies on chemotactic signals for movement through tsetse fly tissues, but the molecular basis is unknown. Here, the authors show that flagellar cAMP signaling is required for traversal of the peritrophic matrix and that, without it, parasites are trapped in the midgut lumen.
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Affiliation(s)
- Sebastian Shaw
- Institute of Cell Biology, University of Bern, Baltzerstrasse 4, CH-3012, Bern, Switzerland.,Graduate School for Cellular and Biomedical Sciences, University of Bern, CH-3012, Bern, Switzerland
| | - Stephanie F DeMarco
- Molecular Biology Institute, University of California, Los Angeles, CA, 90095, USA
| | - Ruth Rehmann
- Institute of Cell Biology, University of Bern, Baltzerstrasse 4, CH-3012, Bern, Switzerland
| | - Tanja Wenzler
- Institute of Cell Biology, University of Bern, Baltzerstrasse 4, CH-3012, Bern, Switzerland
| | - Francesca Florini
- Institute of Cell Biology, University of Bern, Baltzerstrasse 4, CH-3012, Bern, Switzerland.,Graduate School for Cellular and Biomedical Sciences, University of Bern, CH-3012, Bern, Switzerland
| | - Isabel Roditi
- Institute of Cell Biology, University of Bern, Baltzerstrasse 4, CH-3012, Bern, Switzerland.
| | - Kent L Hill
- Molecular Biology Institute, University of California, Los Angeles, CA, 90095, USA. .,Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, CA, 90095, USA. .,California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA.
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18
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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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19
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Sebastián-Pérez V, Hendrickx S, Munday JC, Kalejaiye T, Martínez A, Campillo NE, de Koning H, Caljon G, Maes L, Gil C. Cyclic Nucleotide-Specific Phosphodiesterases as Potential Drug Targets for Anti-Leishmania Therapy. Antimicrob Agents Chemother 2018; 62:e00603-18. [PMID: 30104270 PMCID: PMC6153811 DOI: 10.1128/aac.00603-18] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 08/05/2018] [Indexed: 01/22/2023] Open
Abstract
The available treatments for leishmaniasis are less than optimal due to inadequate efficacy, toxic side effects, and the emergence of resistant strains, clearly endorsing the urgent need for discovery and development of novel drug candidates. Ideally, these should act via an alternative mechanism of action to avoid cross-resistance with the current drugs. As cyclic nucleotide-specific phosphodiesterases (PDEs) of Leishmania major have been postulated as putative drug targets, a series of potential inhibitors of Leishmania PDEs were explored. Several displayed potent and selective in vitro activity against L. infantum intracellular amastigotes. One imidazole derivative, compound 35, was shown to reduce the parasite loads in vivo and to increase the cellular cyclic AMP (cAMP) level at in a dose-dependent manner at just 2× and 5× the 50% inhibitory concentration (IC50), indicating a correlation between antileishmanial activity and increased cellular cAMP levels. Docking studies and molecular dynamics simulations pointed to imidazole 35 exerting its activity through PDE inhibition. This study establishes for the first time that inhibition of cAMP PDEs can potentially be exploited for new antileishmanial chemotherapy.
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Affiliation(s)
| | - Sarah Hendrickx
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Antwerp, Belgium
| | - Jane C Munday
- Institute of Infection, Inflammation and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Titilola Kalejaiye
- Institute of Infection, Inflammation and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Ana Martínez
- Centro de Investigaciones Biológicas (CIB, CSIC), Madrid, Spain
| | | | - Harry de Koning
- Institute of Infection, Inflammation and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Guy Caljon
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Antwerp, Belgium
| | - Louis Maes
- Laboratory for Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, Antwerp, Belgium
| | - Carmen Gil
- Centro de Investigaciones Biológicas (CIB, CSIC), Madrid, Spain
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20
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Blaazer AR, Singh AK, de Heuvel E, Edink E, Orrling KM, Veerman JJN, van den Bergh T, Jansen C, Balasubramaniam E, Mooij WJ, Custers H, Sijm M, Tagoe DNA, Kalejaiye TD, Munday JC, Tenor H, Matheeussen A, Wijtmans M, Siderius M, de Graaf C, Maes L, de Koning HP, Bailey DS, Sterk GJ, de Esch IJP, Brown DG, Leurs R. Targeting a Subpocket in Trypanosoma brucei Phosphodiesterase B1 (TbrPDEB1) Enables the Structure-Based Discovery of Selective Inhibitors with Trypanocidal Activity. J Med Chem 2018; 61:3870-3888. [PMID: 29672041 PMCID: PMC5949723 DOI: 10.1021/acs.jmedchem.7b01670] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
![]()
Several trypanosomatid
cyclic nucleotide phosphodiesterases (PDEs)
possess a unique, parasite-specific cavity near the ligand-binding
region that is referred to as the P-pocket. One of these enzymes, Trypanosoma brucei PDE B1 (TbrPDEB1), is considered a drug
target for the treatment of African sleeping sickness. Here, we elucidate
the molecular determinants of inhibitor binding and reveal that the
P-pocket is amenable to directed design. By iterative cycles of design,
synthesis, and pharmacological evaluation and by elucidating the structures
of inhibitor-bound TbrPDEB1, hPDE4B, and hPDE4D complexes, we have
developed 4a,5,8,8a-tetrahydrophthalazinones as the first selective
TbrPDEB1 inhibitor series. Two of these, 8 (NPD-008)
and 9 (NPD-039), were potent (Ki = 100 nM) TbrPDEB1 inhibitors with antitrypanosomal effects
(IC50 = 5.5 and 6.7 μM, respectively). Treatment
of parasites with 8 caused an increase in intracellular
cyclic adenosine monophosphate (cAMP) levels and severe disruption
of T. brucei cellular organization, chemically validating
trypanosomal PDEs as therapeutic targets in trypanosomiasis.
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Affiliation(s)
- Antoni R Blaazer
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems , Vrije Universiteit Amsterdam , 1081 HZ Amsterdam , The Netherlands
| | - Abhimanyu K Singh
- School of Biosciences , University of Kent , Canterbury CT2 7NJ , U.K
| | - Erik de Heuvel
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems , Vrije Universiteit Amsterdam , 1081 HZ Amsterdam , The Netherlands
| | - Ewald Edink
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems , Vrije Universiteit Amsterdam , 1081 HZ Amsterdam , The Netherlands
| | - Kristina M Orrling
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems , Vrije Universiteit Amsterdam , 1081 HZ Amsterdam , The Netherlands
| | | | | | - Chimed Jansen
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems , Vrije Universiteit Amsterdam , 1081 HZ Amsterdam , The Netherlands
| | | | - Wouter J Mooij
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems , Vrije Universiteit Amsterdam , 1081 HZ Amsterdam , The Netherlands
| | - Hans Custers
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems , Vrije Universiteit Amsterdam , 1081 HZ Amsterdam , The Netherlands
| | - Maarten Sijm
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems , Vrije Universiteit Amsterdam , 1081 HZ Amsterdam , The Netherlands
| | - Daniel N A Tagoe
- Institute of Infection, Immunity and Inflammation , University of Glasgow , Glasgow G12 8TA , U.K
| | - Titilola D Kalejaiye
- Institute of Infection, Immunity and Inflammation , University of Glasgow , Glasgow G12 8TA , U.K
| | - Jane C Munday
- Institute of Infection, Immunity and Inflammation , University of Glasgow , Glasgow G12 8TA , U.K
| | | | - An Matheeussen
- Laboratory for Microbiology, Parasitology and Hygiene , University of Antwerp , 2610 Wilrijk , Belgium
| | - Maikel Wijtmans
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems , Vrije Universiteit Amsterdam , 1081 HZ Amsterdam , The Netherlands
| | - Marco Siderius
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems , Vrije Universiteit Amsterdam , 1081 HZ Amsterdam , The Netherlands
| | - Chris de Graaf
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems , Vrije Universiteit Amsterdam , 1081 HZ Amsterdam , The Netherlands
| | - Louis Maes
- Laboratory for Microbiology, Parasitology and Hygiene , University of Antwerp , 2610 Wilrijk , Belgium
| | - Harry P de Koning
- Institute of Infection, Immunity and Inflammation , University of Glasgow , Glasgow G12 8TA , U.K
| | | | - Geert Jan Sterk
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems , Vrije Universiteit Amsterdam , 1081 HZ Amsterdam , The Netherlands
| | - Iwan J P de Esch
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems , Vrije Universiteit Amsterdam , 1081 HZ Amsterdam , The Netherlands
| | - David G Brown
- School of Biosciences , University of Kent , Canterbury CT2 7NJ , U.K
| | - Rob Leurs
- Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems , Vrije Universiteit Amsterdam , 1081 HZ Amsterdam , The Netherlands
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21
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The single cyclic nucleotide-specific phosphodiesterase of the intestinal parasite Giardia lamblia represents a potential drug target. PLoS Negl Trop Dis 2017; 11:e0005891. [PMID: 28915270 PMCID: PMC5617230 DOI: 10.1371/journal.pntd.0005891] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 09/27/2017] [Accepted: 08/21/2017] [Indexed: 01/08/2023] Open
Abstract
Background Giardiasis is an intestinal infection correlated with poverty and poor drinking water quality, and treatment options are limited. According to the Center for Disease Control and Prevention, Giardia infections afflict nearly 33% of people in developing countries, and 2% of the adult population in the developed world. This study describes the single cyclic nucleotide-specific phosphodiesterase (PDE) of G. lamblia and assesses PDE inhibitors as a new generation of anti-giardial drugs. Methods An extensive search of the Giardia genome database identified a single gene coding for a class I PDE, GlPDE. The predicted protein sequence was analyzed in-silico to characterize its domain structure and catalytic domain. Enzymatic activity of GlPDE was established by complementation of a PDE-deficient Saccharomyces cerevisiae strain, and enzyme kinetics were characterized in soluble yeast lysates. The potency of known PDE inhibitors was tested against the activity of recombinant GlPDE expressed in yeast and against proliferating Giardia trophozoites. Finally, the localization of epitope-tagged and ectopically expressed GlPDE in Giardia cells was investigated. Results Giardia encodes a class I PDE. Catalytically important residues are fully conserved between GlPDE and human PDEs, but sequence differences between their catalytic domains suggest that designing Giardia-specific inhibitors is feasible. Recombinant GlPDE hydrolyzes cAMP with a Km of 408 μM, and cGMP is not accepted as a substrate. A number of drugs exhibit a high degree of correlation between their potency against the recombinant enzyme and their inhibition of trophozoite proliferation in culture. Epitope-tagged GlPDE localizes as dots in a pattern reminiscent of mitosomes and to the perinuclear region in Giardia. Conclusions Our data strongly suggest that inhibition of G. lamblia PDE activity leads to a profound inhibition of parasite proliferation and that GlPDE is a promising target for developing novel anti-giardial drugs. Cellular signaling by the cyclic nucleotides cAMP and cGMP is ubiquitously found in organisms from human to unicellular parasites. Cyclic nucleotide-specific phosphodiesterases (PDEs) are pivotal regulators of these signaling processes and these enzymes represent important drug targets for a variety of diseases. Eleven PDE families are distinguished in humans and selective inhibition of a single human PDE family without targeting others is feasible. In parasites, interference in the signaling mechanism by PDE inhibition may be fatal. The diarrhea-causing parasite Giardia lamblia contains only one single PDE, named GlPDE. GlPDE activity is highly impaired by a range of PDE inhibitors, which also suppress parasite proliferation in vitro. Thus, there is a good agreement between PDE inhibition and parasite drug susceptibility. We demonstrate molecular differences between human PDEs and GlPDE that can be exploited for the development of GlPDE-selective inhibitors. Finally, our data may suggest localization of GlPDE to mitosome organelles, which are absent in human cells and thus are in the focus as possible targets for the treatment of giardiasis. This may add to the notion that GlPDE represents a potential target for the development of novel anti-giardial drugs.
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22
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Long T, Rojo-Arreola L, Shi D, El-Sakkary N, Jarnagin K, Rock F, Meewan M, Rascón AA, Lin L, Cunningham KA, Lemieux GA, Podust L, Abagyan R, Ashrafi K, McKerrow JH, Caffrey CR. Phenotypic, chemical and functional characterization of cyclic nucleotide phosphodiesterase 4 (PDE4) as a potential anthelmintic drug target. PLoS Negl Trop Dis 2017; 11:e0005680. [PMID: 28704396 PMCID: PMC5526615 DOI: 10.1371/journal.pntd.0005680] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 07/25/2017] [Accepted: 06/04/2017] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Reliance on just one drug to treat the prevalent tropical disease, schistosomiasis, spurs the search for new drugs and drug targets. Inhibitors of human cyclic nucleotide phosphodiesterases (huPDEs), including PDE4, are under development as novel drugs to treat a range of chronic indications including asthma, chronic obstructive pulmonary disease and Alzheimer's disease. One class of huPDE4 inhibitors that has yielded marketed drugs is the benzoxaboroles (Anacor Pharmaceuticals). METHODOLOGY/PRINCIPAL FINDINGS A phenotypic screen involving Schistosoma mansoni and 1,085 benzoxaboroles identified a subset of huPDE4 inhibitors that induced parasite hypermotility and degeneration. To uncover the putative schistosome PDE4 target, we characterized four PDE4 sequences (SmPDE4A-D) in the parasite's genome and transcriptome, and cloned and recombinantly expressed the catalytic domain of SmPDE4A. Among a set of benzoxaboroles and catechol inhibitors that differentially inhibit huPDE4, a relationship between the inhibition of SmPDE4A, and parasite hypermotility and degeneration, was measured. To validate SmPDE4A as the benzoxaborole molecular target, we first generated Caenorhabditis elegans lines that express a cDNA for smpde4a on a pde4(ce268) mutant (hypermotile) background: the smpde4a transgene restored mutant worm motility to that of the wild type. We then showed that benzoxaborole inhibitors of SmPDE4A that induce hypermotility in the schistosome also elicit a hypermotile response in the C. elegans lines that express the smpde4a transgene, thereby confirming SmPDE4A as the relevant target. CONCLUSIONS/SIGNIFICANCE The orthogonal chemical, biological and genetic strategies employed identify SmPDE4A's contribution to parasite motility and degeneration, and its potential as a drug target. Transgenic C. elegans is highlighted as a potential screening tool to optimize small molecule chemistries to flatworm molecular drug targets.
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Affiliation(s)
- Thavy Long
- Center for Discovery and Innovation in Parasitic Diseases, University of California San Francisco, San Francisco, California, United States of America
- Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
| | - Liliana Rojo-Arreola
- Center for Discovery and Innovation in Parasitic Diseases, University of California San Francisco, San Francisco, California, United States of America
- Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
| | - Da Shi
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America
| | - Nelly El-Sakkary
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America
| | - Kurt Jarnagin
- Anacor Pharmaceuticals, Inc., Palo Alto, California, United States of America
| | - Fernando Rock
- Anacor Pharmaceuticals, Inc., Palo Alto, California, United States of America
| | - Maliwan Meewan
- Anacor Pharmaceuticals, Inc., Palo Alto, California, United States of America
| | - Alberto A. Rascón
- Center for Discovery and Innovation in Parasitic Diseases, University of California San Francisco, San Francisco, California, United States of America
- Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
| | - Lin Lin
- Department of Physiology, University of California San Francisco, San Francisco, California, United States of America
| | - Katherine A. Cunningham
- Department of Physiology, University of California San Francisco, San Francisco, California, United States of America
| | - George A. Lemieux
- Department of Physiology, University of California San Francisco, San Francisco, California, United States of America
| | - Larissa Podust
- Center for Discovery and Innovation in Parasitic Diseases, University of California San Francisco, San Francisco, California, United States of America
- Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
| | - Ruben Abagyan
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America
| | - Kaveh Ashrafi
- Department of Physiology, University of California San Francisco, San Francisco, California, United States of America
| | - James H. McKerrow
- Center for Discovery and Innovation in Parasitic Diseases, University of California San Francisco, San Francisco, California, United States of America
- Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
| | - Conor R. Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, University of California San Francisco, San Francisco, California, United States of America
- Department of Pathology, University of California San Francisco, San Francisco, California, United States of America
- * E-mail:
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23
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Field MC, Horn D, Fairlamb AH, Ferguson MAJ, Gray DW, Read KD, De Rycker M, Torrie LS, Wyatt PG, Wyllie S, Gilbert IH. Anti-trypanosomatid drug discovery: an ongoing challenge and a continuing need. Nat Rev Microbiol 2017; 15:217-231. [PMID: 28239154 PMCID: PMC5582623 DOI: 10.1038/nrmicro.2016.193] [Citation(s) in RCA: 263] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The WHO recognizes human African trypanosomiasis, Chagas disease and the leishmaniases as neglected tropical diseases. These diseases are caused by parasitic trypanosomatids and range in severity from mild and self-curing to near invariably fatal. Public health advances have substantially decreased the effect of these diseases in recent decades but alone will not eliminate them. In this Review, we discuss why new drugs against trypanosomatids are required, approaches that are under investigation to develop new drugs and why the drug discovery pipeline remains essentially unfilled. In addition, we consider the important challenges to drug discovery strategies and the new technologies that can address them. The combination of new drugs, new technologies and public health initiatives is essential for the management, and hopefully eventual elimination, of trypanosomatid diseases from the human population.
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Affiliation(s)
- Mark C Field
- Wellcome Centre for Anti-Infectives Research, University of Dundee, Dundee DD1 5EH, UK
| | - David Horn
- Wellcome Centre for Anti-Infectives Research, University of Dundee, Dundee DD1 5EH, UK
| | - Alan H Fairlamb
- Wellcome Centre for Anti-Infectives Research, University of Dundee, Dundee DD1 5EH, UK
| | - Michael A J Ferguson
- Wellcome Centre for Anti-Infectives Research, University of Dundee, Dundee DD1 5EH, UK
| | - David W Gray
- Wellcome Centre for Anti-Infectives Research, University of Dundee, Dundee DD1 5EH, UK
| | - Kevin D Read
- Wellcome Centre for Anti-Infectives Research, University of Dundee, Dundee DD1 5EH, UK
| | - Manu De Rycker
- Wellcome Centre for Anti-Infectives Research, University of Dundee, Dundee DD1 5EH, UK
| | - Leah S Torrie
- Wellcome Centre for Anti-Infectives Research, University of Dundee, Dundee DD1 5EH, UK
| | - Paul G Wyatt
- Wellcome Centre for Anti-Infectives Research, University of Dundee, Dundee DD1 5EH, UK
| | - Susan Wyllie
- Wellcome Centre for Anti-Infectives Research, University of Dundee, Dundee DD1 5EH, UK
| | - Ian H Gilbert
- Wellcome Centre for Anti-Infectives Research, University of Dundee, Dundee DD1 5EH, UK
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24
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Akhtar W, Shaquiquzzaman M, Akhter M, Verma G, Khan MF, Alam MM. The therapeutic journey of pyridazinone. Eur J Med Chem 2016; 123:256-281. [DOI: 10.1016/j.ejmech.2016.07.061] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Revised: 07/20/2016] [Accepted: 07/24/2016] [Indexed: 11/17/2022]
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