{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T09:37:38Z","timestamp":1792143458452,"version":"4.4.0"},"reference-count":26,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2012,12,27]],"date-time":"2012-12-27T00:00:00Z","timestamp":1356566400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Pentas micrantha is used in the East African indigenous medicine to treat malaria. In the first investigation of this plant, the crude methanol root extract showed moderate antiplasmodial activity against the W2- (3.37 \u03bcg\/mL) and D6-strains (4.00 \u03bcg\/mL) of Plasmodium falciparum and low cytotoxicity (&gt;450 \u03bcg\/mL, MCF-7 cell line). Chromatographic separation of the extract yielded nine anthraquinones, of which 5,6-dihydroxylucidin-11-O-methyl ether is new. Isolation of a munjistin derivative from the genus Pentas is reported here for the first time. The isolated constituents were identified by NMR and mass spectrometric techniques and showed low antiplasmodial activities.<\/jats:p>","DOI":"10.3390\/molecules18010311","type":"journal-article","created":{"date-parts":[[2012,12,27]],"date-time":"2012-12-27T11:08:31Z","timestamp":1356606511000},"page":"311-321","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Anthraquinones of the Roots of Pentas micrantha"],"prefix":"10.3390","volume":"18","author":[{"given":"Milkyas","family":"Endale","sequence":"first","affiliation":[{"name":"Department of Chemistry, University of Nairobi, P.O. Box 30197-00100, Nairobi, Kenya"},{"name":"Department of Chemistry and Molecular Biology, University of Gothenburg, SE-412 96 Gothenburg, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Annabel","family":"Ekberg","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Molecular Biology, University of Gothenburg, SE-412 96 Gothenburg, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John","family":"Alao","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Molecular Biology, University of Gothenburg, SE-412 96 Gothenburg, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hoseah","family":"Akala","sequence":"additional","affiliation":[{"name":"United States Army Medical Research Unit-Kenya, MRU 64109, APO, AE 09831, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Albert","family":"Ndakala","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Nairobi, P.O. Box 30197-00100, Nairobi, Kenya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Per","family":"Sunnerhagen","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Molecular Biology, University of Gothenburg, SE-412 96 Gothenburg, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0359-5970","authenticated-orcid":false,"given":"M\u00e1t\u00e9","family":"Erd\u00e9lyi","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Molecular Biology, University of Gothenburg, SE-412 96 Gothenburg, Sweden"},{"name":"Swedish NMR Center, University of Gothenburg, P.O. Box 465, SE-405 30 Gothenburg, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abiy","family":"Yenesew","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Nairobi, P.O. Box 30197-00100, Nairobi, Kenya"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2012,12,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1186\/1746-4269-2-8","article-title":"Diversity and utilization of antimalarial ethnophytotherapeutic remedies among the Kikuyus (Central Kenya)","volume":"2","author":"Njoroge","year":"2006","journal-title":"J. Ethnobiol. Ethnomed."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"201","DOI":"10.1023\/A:1012758922713","article-title":"Biosynthesis of anthraquinones in cell cultures of the Rubiaceae","volume":"67","author":"Han","year":"2001","journal-title":"Plant. Cell Tiss. 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