{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,13]],"date-time":"2026-05-13T16:18:05Z","timestamp":1778689085946,"version":"3.51.4"},"reference-count":37,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2020,4,17]],"date-time":"2020-04-17T00:00:00Z","timestamp":1587081600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100010798","name":"Sunway University","doi-asserted-by":"publisher","award":["DBS"],"award-info":[{"award-number":["DBS"]}],"id":[{"id":"10.13039\/501100010798","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002724","name":"American University of Sharjah","doi-asserted-by":"publisher","award":["BCE"],"award-info":[{"award-number":["BCE"]}],"id":[{"id":"10.13039\/501100002724","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Balamuthia mandrillaris and Naegleria fowleri are opportunistic protozoan pathogens capable of producing infection of the central nervous system with more than 95% mortality rate. Previously, we have synthesized several compounds with antiamoebic properties; however, synthesis of compounds that are analogues of clinically used drugs is a highly desirable approach that can lead to effective drug development against these devastating infections. In this regard, compounds belonging to the azole class possess wide range of antimicrobial properties and used clinically. In this study, six novel benzimidazole, indazole, and tetrazole derivatives were synthesized and tested against brain-eating amoebae. These compounds were tested for their amoebicidal and static properties against N. fowleri and B. mandrillaris. Furthermore, the compounds were conjugated with silver nanoparticles and characterized. The synthetic heterocyclic compounds showed up to 72% and 65% amoebicidal activities against N. fowleri and B. mandrillaris respectively, while expressing up to 75% and 70% amoebistatic activities, respectively. Following conjugation with silver nanoparticles, amoebicidal activities of the drugs increased by up to 46 and 36% versus B. mandrillaris and N. fowleri. Minimal effects were observed when the compounds were evaluated against human cells using cytotoxicity assays. In summary, azole compounds exhibited potent activity against N. fowleri and B. mandrillaris. Moreover, conjugation of the azole compounds with silver nanoparticles further augmented the capabilities of the compounds against amoebae.<\/jats:p>","DOI":"10.3390\/antibiotics9040188","type":"journal-article","created":{"date-parts":[[2020,4,21]],"date-time":"2020-04-21T03:23:06Z","timestamp":1587439386000},"page":"188","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Novel Azoles as Antiparasitic Remedies against Brain-Eating Amoebae"],"prefix":"10.3390","volume":"9","author":[{"given":"Ayaz","family":"Anwar","sequence":"first","affiliation":[{"name":"Department of Biological Sciences, School of Science and Technology, Sunway University, Petaling Jaya, Selangor 47500, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mohammad Ridwane","family":"Mungroo","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, School of Science and Technology, Sunway University, Petaling Jaya, Selangor 47500, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Simal","family":"Khan","sequence":"additional","affiliation":[{"name":"Department of Biotechnology, Government College University, Lahore 54000, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Itrat","family":"Fatima","sequence":"additional","affiliation":[{"name":"H. E. J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rafaila","family":"Rafique","sequence":"additional","affiliation":[{"name":"H. E. J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"family":"Kanwal","sequence":"additional","affiliation":[{"name":"Institute of Marine Biotechnology, Universiti Malaysia Terengganu, Kuala Terengganu, Terengganu 21030, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Khalid Mohammed","family":"Khan","sequence":"additional","affiliation":[{"name":"H. E. J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan"},{"name":"Department of Clinical Pharmacy, Institute for Research and Medical Consultations (IRMC), Imam Abdulrahman Bin Faisal University, P.O. Box 1982, Dammam 31441, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9646-6208","authenticated-orcid":false,"given":"Ruqaiyyah","family":"Siddiqui","sequence":"additional","affiliation":[{"name":"Department of Biology, Chemistry and Environmental Sciences, American University of Sharjah, Sharjah 26666, UAE"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7667-8553","authenticated-orcid":false,"given":"Naveed Ahmed","family":"Khan","sequence":"additional","affiliation":[{"name":"Department of Biology, Chemistry and Environmental Sciences, American University of Sharjah, Sharjah 26666, UAE"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,4,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1016\/j.drup.2004.01.002","article-title":"Opportunistic amoebae: Challenges in prophylaxis and treatment","volume":"7","author":"Schuster","year":"2004","journal-title":"Drug Resist. 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