Ramli R.A.Pudjiastuti P.Tjahjandaric T.S.Lie W.Rattanajak R.Kamchonwongapaisan S.Pyne S.G.2024-05-282024-05-2820151874390010.1016/j.phytol.2014.12.0092-s2.0-84920085367https://www.scopus.com/inward/record.uri?eid=2-s2.0-84920085367&doi=10.1016%2fj.phytol.2014.12.009&partnerID=40&md5=5cb658ff84981bb4dc9921f4d785eca4https://oarep.usim.edu.my/handle/123456789/9123Two new protostemonine-type alkaloids, javastemonine A and B (3 and 4) have been isolated from the root extracts of Stemona javanica together with four known Stemona alkaloids, 13-demethoxy-11(S∗),12(R∗)-dihydroprotostemonine (1), isoprotostemonine (2), protostemonine and isomaistemonine. The structures and relative configurations of the new alkaloids were determined by spectroscopic analysis. The alkaloids 1 and 2 and protostemonine showed moderated antiplasmodial activities against the Plasmodium falciparum strains, TM4 (IC50 values of 17.7 ± 3.7, 16.8 ± 5.4, 16.0 ± 4.2 μg/mL, respectively) and K1 (IC50 values of 16.8 ± 3.1, 14.1 ± 3.7, 11.9 ± 3.3 μg/mL, respectively). These compounds showed no significant cytotoxicities against KB or Vero cells or acetylcholinesterase inhibitory activities.en-USAnti-malarialCytotoxicityHuman acetylcholinesteraseJavastemonine A and BStemona javanicaArticle15716211PLHEB