title: Unusual antimalarial meroditerpenes from tropical red macroalgae.
abstract: Three antimalarial meroditerpenes have been isolated from two Fijian red macroalgae. The absolute stereochemistry of callophycolide A (1), a unique macrolide from Callophycus serratus, was determined using a combination of Mosher's ester analysis, circular dichroism analysis with a dimolybdenum tetraacetate complex, and conformational analysis using NOEs. In addition, two known tocopherols, β-tocopherylhydroquinone (4) and δ-tocopherylhydroquinone (5), were isolated from Amphiroa crassa. By oxidizing 5 to the corresponding δ-tocopherylquinone (6), antimalarial activity against the human malaria parasite Plasmodium falciparum was increased by more than 20-fold.
authors.affiliation: School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA.
authors.forename: E Paige
authors.initials: EP
authors.lastname: Stout
authors.forename: Jacques
authors.initials: J
authors.lastname: Prudhomme
authors.forename: Karine Le
authors.initials: KL
authors.lastname: Roch
authors.forename: Craig R
authors.initials: CR
authors.lastname: Fairchild
authors.forename: Scott G
authors.initials: SG
authors.lastname: Franzblau
authors.forename: William
authors.initials: W
authors.lastname: Aalbersberg
authors.forename: Mark E
authors.initials: ME
authors.lastname: Hay
authors.forename: Julia
authors.initials: J
authors.lastname: Kubanek
mesh_terms: D000962:Antimalarials / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D002942:Circular Dichroism; D004224:Diterpenes / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D006801:Humans; D010963:Plasmodium falciparum / Q000187:drug effects; D012624:Seaweed / Q000737:chemistry*
chemical_list: D000962:Antimalarials; D004224:Diterpenes
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