{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:28:19Z","timestamp":1760236099607,"version":"build-2065373602"},"reference-count":49,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,10,30]],"date-time":"2021-10-30T00:00:00Z","timestamp":1635552000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceuticals"],"abstract":"<jats:p>The 2-phenoxybenzamide 1 from the Medicines for Malaria Venture Malaria Box Project has shown promising multi-stage activity against different strains of P. falciparum. It was successfully synthesized via a retrosynthetic approach. Subsequently, twenty-one new derivatives were prepared and tested for their in vitro activity against blood stages of the NF54 strain of P. falciparum. Several insights into structure-activity relationships were revealed. The antiplasmodial activity and cytotoxicity of compounds strongly depended on the substitution pattern of the anilino partial structure as well as on the size of substituents. The diaryl ether partial structure had further impacts on the activity. Additionally, several physicochemical and pharmacokinetic parameters were calculated (log P, log D7.4 and ligand efficiency) or determined experimentally (passive permeability and CYP3A4 inhibition). The tert-butyl-4-{4-[2-(4-fluorophenoxy)-3-(trifluoromethyl)benzamido]phenyl}piperazine-1-carboxylate possesses high antiplasmodial activity against P. falciparum NF54 (PfNF54 IC50 = 0.2690 \u00b5M) and very low cytotoxicity (L-6 cells IC50 = 124.0 \u00b5M) resulting in an excellent selectivity index of 460. Compared to the lead structure 1 the antiplasmodial activity was improved as well as the physicochemical and some pharmacokinetic parameters.<\/jats:p>","DOI":"10.3390\/ph14111109","type":"journal-article","created":{"date-parts":[[2021,11,1]],"date-time":"2021-11-01T22:24:22Z","timestamp":1635805462000},"page":"1109","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Synthesis and Structure-Activity Relationships of New 2-Phenoxybenzamides with Antiplasmodial Activity"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5267-7852","authenticated-orcid":false,"given":"Theresa","family":"Hermann","sequence":"first","affiliation":[{"name":"Institute of Pharmaceutical Sciences, Pharmaceutical Chemistry, University of Graz, Schubertstra\u00dfe 1, A-8010 Graz, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3995-2186","authenticated-orcid":false,"given":"Patrick","family":"Hochegger","sequence":"additional","affiliation":[{"name":"Institute of Pharmaceutical Sciences, Pharmaceutical Chemistry, University of Graz, Schubertstra\u00dfe 1, A-8010 Graz, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Johanna","family":"Dolensky","sequence":"additional","affiliation":[{"name":"Institute of Pharmaceutical Sciences, Pharmaceutical Chemistry, University of Graz, Schubertstra\u00dfe 1, A-8010 Graz, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Werner","family":"Seebacher","sequence":"additional","affiliation":[{"name":"Institute of Pharmaceutical Sciences, Pharmaceutical Chemistry, University of Graz, Schubertstra\u00dfe 1, A-8010 Graz, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8327-0732","authenticated-orcid":false,"given":"Eva-Maria","family":"Pferschy-Wenzig","sequence":"additional","affiliation":[{"name":"Institute of Pharmaceutical Sciences, Pharmacognosy, University of Graz, Beethovenstra\u00dfe 8, A-8010 Graz, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Robert","family":"Saf","sequence":"additional","affiliation":[{"name":"Institute for Chemistry and Technology of Materials (ICTM), Graz University of Technology, Stremayrgasse 9, A-8010 Graz, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marcel","family":"Kaiser","sequence":"additional","affiliation":[{"name":"Swiss Tropical and Public Health Institute, Socinstra\u00dfe 57, CH-4002 Basel, Switzerland"},{"name":"Swiss TPH, University of Basel, Petersplatz 1, CH-4001 Basel, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3122-1941","authenticated-orcid":false,"given":"Pascal","family":"M\u00e4ser","sequence":"additional","affiliation":[{"name":"Swiss Tropical and Public Health Institute, Socinstra\u00dfe 57, CH-4002 Basel, Switzerland"},{"name":"Swiss TPH, University of Basel, Petersplatz 1, CH-4001 Basel, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7174-6673","authenticated-orcid":false,"given":"Robert","family":"Weis","sequence":"additional","affiliation":[{"name":"Institute of Pharmaceutical Sciences, Pharmaceutical Chemistry, University of Graz, Schubertstra\u00dfe 1, A-8010 Graz, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,30]]},"reference":[{"key":"ref_1","unstructured":"WHO (2021). 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