title: Weakly antimalarial flavonol arabinofuranosides from Calycolpus warszewiczianus.
abstract: Three new flavonol arabinosides (2-4) were isolated from the young leaves of Calycolpus warszewiczianus. The structures were determined as myricetin-3-O-alpha-L-3' '-acetylarabinofuranoside (2), myricetin-3-O-alpha-L-3' ',5' '-diacetylarabinofuranoside (3), and 5-galloylquercetin-3-O-alpha-L-arabinofuranoside (4). Molecular structures were elucidated using NMR spectroscopy in combination with IR and MS data. Two known compounds, myricetin-3-O-alpha-L-arabinofuranoside (1) and (-)-epi-catechin (5), were also isolated. The compounds were tested in vitro against a chloroquine-resistant strain of Plasmodium falciparum, Leishmania mexicana, and Trypanosoma cruzi parasites. Compound 4 demonstrated weak activity against a chloroquine-resistant strain of P. falciparum (14.5 microM), whereas none of the compounds demonstrated activity against L. mexicana and T. cruzi at the concentrations of 40 and 50 microg/mL, respectively, and no cytotoxicity was detected against mammalian cells below 100 microg/mL.
authors.affiliation: Laboratory of Tropical Bioorganic Chemistry, Faculty of Natural, Exact Sciences and Technology, University of Panama, Panama City, Republic of Panama.
authors.forename: Daniel
authors.initials: D
authors.lastname: Torres-Mendoza
authors.forename: José
authors.initials: J
authors.lastname: González
authors.forename: Eduardo
authors.initials: E
authors.lastname: Ortega-Barría
authors.forename: María V
authors.initials: MV
authors.lastname: Heller
authors.forename: Todd L
authors.initials: TL
authors.lastname: Capson
authors.forename: Kerry
authors.initials: K
authors.lastname: McPhail
authors.forename: William H
authors.initials: WH
authors.lastname: Gerwick
authors.forename: Luis
authors.initials: L
authors.lastname: Cubilla-Rios
mesh_terms: D000818:Animals; D000962:Antimalarials / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D000981:Antiprotozoal Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D001089:Arabinose / Q000031:analogs & derivatives / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D002738:Chloroquine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004351:Drug Resistance; D044948:Flavonols / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D007894:Leishmania mexicana / Q000187:drug effects; D015394:Molecular Structure; D027822:Myrtaceae / Q000737:chemistry*; D010176:Panama; D010946:Plants, Medicinal / Q000737:chemistry*; D010963:Plasmodium falciparum / Q000187:drug effects; D014349:Trypanosoma cruzi / Q000187:drug effects
chemical_list: D000962:Antimalarials; D000981:Antiprotozoal Agents; D044948:Flavonols; D002738:Chloroquine; D001089:Arabinose