{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,9]],"date-time":"2026-03-09T02:59:02Z","timestamp":1773025142963,"version":"3.50.1"},"reference-count":32,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2022,12,30]],"date-time":"2022-12-30T00:00:00Z","timestamp":1672358400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>2,4-Diaminopyrimidines and (dialkylamino)azabicyclo-nonanes possess activity against protozoan parasites. A series of fused hybrids were synthesized and tested in vitro against pathogens of malaria tropica and sleeping sickness. The activities and selectivities of compounds strongly depended on the substitution pattern of both ring systems as well as on the position of the nitrogen atom in the bicycles. The most promising hybrids of 3-azabicyclo-nonane with 2-aminopyrimidine showed activity against P. falciparum NF54 in submicromolar concentration and high selectivity. A hybrid with pyrrolidino substitution of the 2-azabicyclo-nonane as well as of the pyrimidine moiety exhibited promising activity against the multiresistant K1 strain of P. falciparum. A couple of hybrids of 2-azabicyclo-nonanes with 2-(dialkylamino)pyrimidines possessed high activity against Trypanosoma brucei rhodesiense STIB900 and good selectivity.<\/jats:p>","DOI":"10.3390\/molecules28010307","type":"journal-article","created":{"date-parts":[[2023,1,2]],"date-time":"2023-01-02T03:00:59Z","timestamp":1672628459000},"page":"307","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Synthesis and Antiprotozoal Activity of Azabicyclo-Nonane Pyrimidine Hybrids"],"prefix":"10.3390","volume":"28","author":[{"given":"Clemens","family":"Hinteregger","sequence":"first","affiliation":[{"name":"Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, University of Graz, Schubertstra\u00dfe 1, A-8010 Graz, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Johanna","family":"Dolensky","sequence":"additional","affiliation":[{"name":"Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, University of Graz, Schubertstra\u00dfe 1, A-8010 Graz, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5673-0470","authenticated-orcid":false,"given":"Werner","family":"Seebacher","sequence":"additional","affiliation":[{"name":"Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, University of Graz, Schubertstra\u00dfe 1, 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"}]},{"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, Kreuzstra\u00dfe 2, CH-4123 Allschwil, Switzerland"},{"name":"Swiss Tropical and Public Health Institute, University of Basel, Petersplatz 1, CH-4003 Basel, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1785-7302","authenticated-orcid":false,"given":"Marcel","family":"Kaiser","sequence":"additional","affiliation":[{"name":"Swiss Tropical and Public Health Institute, Kreuzstra\u00dfe 2, CH-4123 Allschwil, Switzerland"},{"name":"Swiss Tropical and Public Health Institute, University of Basel, Petersplatz 1, CH-4003 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":"Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, University of Graz, Schubertstra\u00dfe 1, A-8010 Graz, Austria"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,30]]},"reference":[{"key":"ref_1","unstructured":"WHO (2021). 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