Location: Natural Products Utilization ResearchTitle: Isolation and characterization of secondary metabolites from Asphodelus microcarpus) Author
Submitted to: Medicnal Chemistry Research
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/24/2014
Publication Date: 2/11/2014
Citation: Ghoneim, M.M., Elokely, K.M., El-Hela, A.A., Mohammad, A.I., Jacob, M., Cutler, S.J., Doerksen, R.J., Ross, S. 2014. Isolation and characterization of secondary metabolites from Asphodelus microcarpus. Medicnal Chemistry Research. 23:3510-3515. Interpretive Summary: The bulbs and roots of Asphodelus microcarpus are used to treat ectodermal parasites, jaundice, and psoriasis, by Bedouins as an antimicrobial agent so we tried to isolate and identify these active metabolites. This work resulted in the isolation of Five compounds (two new) were isolated from the Asphodelus microcarpus. Compound 3 exhibited antileishmanial activity with IC50 value of 33.2 µg/mL. Compound 2 features an unusual structure including an epoxybenzo[h] isochromene ring structure. The absolute configuration of 2 was assigned by a combination of experimental and computational techniques to be R enantiomer. The result of this work could improve our goal to treat infective diseases from natural sources.
Technical Abstract: Bioassay guided fractionation of the ethanolic extract of Asphodelus microcarpus Salzm.et Vivi (Asphodelaceae) resulted in the isolation of two hitherto unknown compounds , methy-1, 4, 5-trihydroxy-7-methyl-9,10-dioxo-9,10dihydroanthracene-2-carboxylate (1) and (1R) 3, 10-dimethoxy-5-methyl-1H-1,4-epoxybenzo[h]isochromene (2) as well as 3 known compounds: benzoic acid, 3, 4-dihydroxy-methyl ester (3), 3, 4-dihydroxybenzoic acid (4), and 6-methoxy chrysophanol (5). Compounds (3) showed antileishmanial activity with an IC50 value of 33.2 µg/mL. Compound 2 is the first natural product possessing a highly strained 1, 4-epoxy moiety. The structure elucidation of isolated metabolites including the absolute configuration of 2 was carried out using spectroscopic data, optical rotation and electronic circular dichroism experiments and calculations.