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Antimalarial aminothiazoles and aminopyridines from phenotypic whole-cell screening of a SoftFocus® library

    Tanya Paquet

    Department of Chemistry, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa

    ,
    Richard Gordon

    Technology Innovation Agency, Black River Parkway, Fir Road, Observatory, Cape Town, 7700, South Africa

    ,
    David Waterson

    Medicines for Malaria Venture, ICC, Route de Pré-Bois 20, PO Box 1826, 1215 Geneva, Switzerland

    ,
    Michael J Witty

    Medicines for Malaria Venture, ICC, Route de Pré-Bois 20, PO Box 1826, 1215 Geneva, Switzerland

    &
    Kelly Chibale

    * Author for correspondence

    Department of Chemistry & Institute of Infectious Disease & Molecular Medicine, University of Cape Town, Private Bag X3, Rondebosch 7701, Cape Town, South Africa.

    Published Online:https://doi.org/10.4155/fmc.12.176

    The current state of antimalarial drug resistance emphasizes the need for new therapies with novel modes of action that will add a significant benefit compared with current standards. In this regard, high throughput phenotypic whole-cell screening aids the discovery of novel antiplasmodial scaffolds that are inherently suited to hit-to-lead and lead-optimization efforts. The aminothiazoles and aminopyridines exemplify two such compound classes stemming from whole-cell screening. Respective structure–activity relationship determinations and subsequent optimization around these scaffolds led to frontrunner compounds in each series, which possess the desired antimalarial efficacy, bioavailability and metabolic stability to further progress medicinal chemistry programs.

    Papers of special note have been highlighted as: ▪ of interest ▪▪ of considerable interest

    References

    • Stepniewska K, White NJ. Pharmacokinetic determinants of the window of selection for antimalarial drug resistance. Antimicrob. Agents Chemother.52(5),1589–1596 (2008).
    • Nosten F, White NJ. Artemisinin-based combination treatment of falciparum malaria. Am. J. Trop. Med. Hyg.77(6),181–192 (2007).
    • Eastman RT, Fidock DA. Artemisinin-based combination therapies: a vital tool in efforts to eliminate malaria. Nat. Rev. Microbiol.7(12),864–874 (2009).
    • Wells TNC, Burrows JN, Baird JK. Targeting the hypnozoite reservoir of Plasmodium vivax: the hidden obstacle to malaria elimination. Trends Parasitol.26(3),145–151 (2010).
    • Brewer GJ, Powell RD, Swanson SH, Alving AS. Hemolytic effect of primaquine. XVII. Hexokinase activity of glucose-6-phosphate dehydrogenase-deficient and normal erythrocytes. Lab. Clin. Med.61,601–612 (1964).
    • Wells TNC, Alonso PL, Gutteridge WE. New medicines to improve control and contribute to the eradication of malaria. Nat. Rev. Drug. Discov.8(11),879–891 (2009).
    • Rodrigues T, Prudencio M, Moreira R, Mota MM, Lopes F. Targeting the liver stage of malaria parasites: a yet unmet goal. J. Med. Chem.55(3),995–1012 (2012).
    • Choi S-R, Mukherjee P, Avery MA. The fight against drug-resistant malaria: novel plasmodial targets and antimalarial drugs. Curr. Med. Chem.15(2),161–171 (2008).
    • Burrows JN, Chibale K, Wells TNC. The state of the art in anti-malarial drug discovery and development. Curr. Top. Med. Chem.11(10),1226–1254 (2011).▪▪ Summary of developed and registered antimalarials, as well as descriptions of new small-molecule antimalarial therapies under development.
    • 10  Plouffe D, Brinker A, McNamara C et al.In silico activity profiling reveals the mechanism of action of antimalarials discovered in a high-throughput screen. Proc. Natl Acad. Sci. USA105(26),9059–9064 (2008).
    • 11  Swinney DC, Anthony J. How were new medicines discovered? Nat. Rev. Drug. Discov.10(7),507–519 (2011).
    • 12  Chatterjee AK, Yeung BKS. Back to the future: lessons learned in modern target-based and whole-cell lead optimization of antimalarials. Curr. Top. Med. Chem.12(5),473–483 (2012).
    • 13  Van Pelt-Koops JC, Pett HE, Graumans W et al. The spiroindolone drug candidate NITD609 potently inhibits gametocytogenesis and blocks Plasmodium falciparum transmission to anopheles mosquito vector. Antimicrob. Agents Chemother.56(7),3544–3548 (2012).
    • 14  Charman SA, Arbe-Barnes S, Bathurst IC et al. Synthetic ozonide drug candidate OZ439 offers new hope for a single-dose cure of uncomplicated malaria. Proc. Natl Acad. Sci. USA108(11),4400–4405 (2011).
    • 15  Vennerstrom JL, Arbe-Barnes S, Brun R et al. Identification of an antimalarial synthetic trioxolane drug development candidate. Nature430(7002),900–904 (2004).
    • 16  Valecha N, Looareesuwan S, Martensson A et al. Arterolane, a new synthetic trioxolane for treatment of uncomplicated Plasmodium falciparum malaria: a Phase II, multicenter, randomized, dose-finding clinical trial. Clin. Infect. Dis.51(6),684–691 (2010).
    • 17  Biot C, Glorian G, Maciejewski LA, Brocard JS. Synthesis and antimalarial activity in vitro and in vivo of a new ferrocene-chloroquine analogue. J. Med. Chem.40(23),3715–3718 (1997).
    • 18  Lee JA, Chu S, Willard FS et al. Open innovation for phenotypic drug discovery: the PD2 assay panel. J. Biomol. Screen.16(6),588–602 (2011).
    • 19  Lee JA, Uhlik MT, Moxham CM, Tomandl D, Sall DJ. Modern phenotypic drug discovery is a viable, neoclassic pharma strategy. J. Med. Chem.55(10),4527–4538 (2012).
    • 20  Payne DJ, Gwynn MN, Holmes DJ, Pompliano DL. Drugs for bad bugs: confronting the challenges of antibacterial discovery. Nat. Rev. Drug. Discov.6(1),29–40 (2007).
    • 21  Guiguemde WA, Shelat AA, Bouck D et al. Chemical genetics of Plasmodium falciparum. Nature465(9107) 311–315 (2010).
    • 22  Duffy S, Avery VM. Development and optimization of a novel 384-well antimalarial imaging assay validated for high-throughput screening. Am. J. Trop. Med. Hyg.86(1),84–92 (2012).
    • 23  Harris CJ, Hill RD, Sheppard DW, Slater MJ, Stouten PFW. The design and application of target-focused compound libraries. Comb. Chem. High Throughput Screen.14(6),521–531 (2011).▪ Description of the rational and advantages of target-focused libraries.
    • 24  Gonzalez Cabrera D, Douelle F, Feng T-S et al. Novel orally active antimalarial thiazoles. J. Med. Chem.54(21),7713–7719 (2011).▪ Identification and optimization of aminothiazoles as antimalarials.
    • 25  Younis Y, Douelle F, Feng T-S et al. 3,5-diaryl-2-aminopyridines as a novel class of orally active antimalarials demonstrating single dose cure in mice and clinical candidate potential. J. Med. Chem.55(7),3479–3487 (2012).▪ Identification and optimization of diarylaminopyridines as antimalarials.
    • 26  Burrows JN, Leroy D, Lotharius J, Waterson D. Challenges in antimalarial drug discovery. Future Med. Chem.3(11),1401–1412 (2011).▪▪ Description of the processes and requirements involved in different areas of antimalarial drug discovery.
    • 27  Selwood DL, Brummell DG, Glen RC et al. Solution-phase parallel synthesis of 5-carboxamido 1-benzyl-3-(3-dimethylaminopropyloxy)-1H-pyrazoles as activators of soluble guanylate cyclase with improved oral bioavailability. Bioorg. Med. Chem. Lett.11(8),1089–1092 (2001).
    • 28  Persson T, Yde CW, Rasmussen JE et al. Pyrazole carboxamides and carboxylic acids as protein kinase inhibitors in aberrant eukaryotic signal transduction: induction of growth arrest in MCF-7 cancer cells. Org. Biomol. Chem.5(24),3963–3970 (2007).
    • 29  Sanguinetti MC, Tristani-Firouzi M. hERG potassium channels and cardiac arrhythmia. Nature,440(4710),463–469 (2006).
    • 30  Carter R, Diggs CL. Plasmodia of rodents. In: Parasitic Protozoa. Kreier JP (Ed.). Academic Press, New York, NY, USA, 359–465 (1977).
    • 31  Fidock DA, Rosenthal PJ, Croft SL, Brun R, Nwaka S. Antimalarial drug discovery: efficacy models for compound screening. Nat. Rev. Drug Discov.3(6),509–520 (2004).
    • 32  Peters W. Drug resistance in Plasmodium berghei. I. Chloroquine resistance. Exptl. Parasitol.17(1),80–89 (1965).
    • 33  Peters W. The chemotherapy of rodent malaria, XXII. The value of drug-resistant strains of P. berghei in screening for blood schizontocidal activity. Ann. Trop. Med. Parasitol.69(2),155–171 (1975).
    • 34  Gamo F-J, Sanz LM, Vidal J et al. Thousands of chemical starting points for antimalarial lead identification. Nature465(9107),305–310 (2010).
    • 35  Yazdi HH, Janahmadi M, Behzadi G. The role of small-conductance Ca2+-activated K+ channels in the modulation of 4-aminopyridine-induced burst firing in rat cerebellar Purkinje cells. Brain Res.1156,59–66 (2007).
    • 101  Ramsden N, Wilson F: WO025820 (2008).
    • 102  Maltais F, Bemis GW, Wang T, Jimenez JM: WO017350 (2010).
    • 103  Paulini K, Gerlach M, Guenther E et al.: WO005484 (2006).
    • 201  World Health Organisation. World malaria report. www.who.int/malaria/world_malaria_report_2011/en/index.html
    • 202  World Health Organisation. Guidelines for the treatment of malaria, second edition (2010). www.who.int/malaria/publications/atoz/9789241547925/en/index.html
    • 203  World Health Organisation. Global report on antimalarial efficacy and drug resistance: 2000–2010 (2010). www.who.int/malaria/publications/atoz/9789241500470/en/index.html
    • 204  Medicines for Malaria Venture. New medicines for malaria control and eradication target product profiles, September (2010). www.mmv.org/research-development/essential-information-scientists/target-product-profiles
    • 205  A service of the U.S. National Institutes of Health. http://clinicaltrials.gov (Accessed September 2012).
    • 206  Medicines for Malaria Venture. Validated hits template (2012). www.mmv.org/research-development/essential-information-scientists