The Antiplasmodial Activity of Isolates from Ajuga remota
摘要:
Ajuga remota is the most frequently used medicinal herb for malaria treatment in Kenya. Its two known isolates ajugarin-1 (1) and ergosterol-5,8-endoperoxide (3) and a new isolate 8-O-acetylharpagide (2) were evaluated for their in vitro antiplasmodial activity. Ajugarin-1 was moderately active, with an IC50 of 23.0 +/- 3.0 muM, as compared to chloroquine (IC50 = 0.041 +/- 0.003 muM) against the chloroquine-sensitive (FCA 20/GHA) strain of Plasmodium falciparum. Ergosterol-5,8-endoperoxide was about 3x as potent (IC50 = 8.2 +/- 1.1 muM), while 8-O-acetylharpagide, whose structure was established by spectroscopic evidence, was inactive. Both ajugarin-1 and ergosterol-5,8-endoperoxide did not exhibit cytotoxicity against A431 (skin carcinoma) cell line, but 8-O-acetylharpagide was significantly cytotoxic. This iridoid glucoside, which has been formerly isolated from Ajuga decumbens, was identified in A. remota for the first time.
[EN] 1 alpha -HYDROXYVITAMIN D2 ANALOGS AND PROCESS FOR PREPARING SAME
申请人:WISCONSIN ALUMNI RESEARCH FOUNDATION
公开号:WO1985003939A1
公开(公告)日:1985-09-12
(EN) Novel vitamin D derivatives, analogs of vitamin D2 compounds which lack the 24-methyl substituent and are identified as 1$g(a)-hydroxy-28-norvitamin D2 and 1$g(a),25-dihydroxy-28-norvitamin D2. The compounds of the invention are characterized by unexpectedly high vitamin D-like activity as well as a novel activity pattern. Because of such activity they would find ready application as substitutes for vitamin D or various of the known vitamin D metabolites in their various application for the treatment of calcium disorders.(FR) Nouveaux dérivés de la vitamine D qui sont des analogues de composés de la vitamine D2 auxquels fait défaut le composant méthyle 24 et qui sont identifiés comme 1 $(a)-hydroxy-28-norvitamine D2 et 1$g(a), 25-dihydroxy-28-norvitamine D2. Les composés de la présente invention sont caractérisés par une activité similaire à la vitamine D surprenament élevée ainsi que par un nouveau spectre d'activité. En raison d'une telle activité, ils trouveraient facilement une application en tant que substituants de la vitamine D ou de divers métabolites connus de la vitamide D dans leurs différentes applications pour le traitement des affections en relation avec le calcium.