Coumarins from Galipea panamensis and Their Activity against Leishmania panamensis

Abstract

Two new coumarin compounds (1 and 2), phebalosin (3), its derived artifact murralongin (4), and murrangatin acetonide (5) were isolated from the leaves of Galipea panamensis. The structures of 1 and 2 were assigned as 7-{[(2R*)-3,3-dimethyloxiran-2-yl]methoxy}-8-[(2R*,3R*)-3-isopropenyloxiran-2-yl]-2H-chromen-2-one and 7-methoxy-8-(4-methyl-3-furyl)-2H-chromen-2-one, respectively, on the basis of their spectroscopic data (primarily NMR and MS). Compounds 1-3 were tested against axenic amastigote forms of Leishmania panamensis and displayed 50% effective concentrations (EC(50)) of 9.9, 10.5, and 14.1 microg/mL, respectively. These three compounds also displayed cytotoxicity (IC(50)) at concentrations of 9.7, 33.0, and 20.7 microg/mL, respectively, on human promonocytic U-937 cells.

Novel Heteroaryl Selenocyanates and Diselenides as Potent Antileishmanial Agents

“…We have payed special attention to quinoline, which constitutes the central nucleus of sitamaquine (25,26), acridine (27,28), quinoxaline (29)(30)(31), and coumarins (32,33). On the other hand, nitrofuran compounds (34,35), the most relevant registered as nifurtimox, and derivatives of the benzodioxol core (36) have been selected.…”

Leishmanicidal and cytotoxic activity of extracts and saponins from <i>Ilex laurina</i> (Aquifoliaceae)

“…The lack of an effective leishmanicidal drug has evoked a renewed interest in medicinal plants as sources of new chemotherapeutic compounds that are more effective and have fewer side effects [6][7][8][9].…”

Artifacts and Natural Substances Formed Spontaneously

“…However, the authors claimed not to have used acetone as solvent, while considering [95] -or not -218 to be an artifact! Notably, the accompanying murralongin (219) [96] -obviously a rearrangement product, as its formation was observed in the course of purification -could have a similar origin (Scheme 24.51).…”