Isolation and evaluation of the cytotoxic properties of peroxisomicine isomers from Karwinskia parvifolia

Abstract

A new compound with a peroxisomicine (dimeric hydroxyanthracenone type) structure was isolated from Karwinskia parvifolia and denominated peroxisomicine A4 (PA4). The stereochemistry of the stereogenic centers of this compound and the previously isolated peroxisomicine A3 (PA3, 3) was elucidated using CD, 13 C NMR and 1 H NMR spectra. Four peroxisomicine stereoisomers were cytotoxic to Chang and HepG2 Liver cells. Only peroxisomicine A1 (PA1, 1) and A3 (PA3, 3) showed selective toxicity. Since 1 and 3 are epimers at C-3' the cytotoxicity results suggest that the stereochemistry at this site may be involved in the cytotoxic properties of these compounds.

Atropisomeric Dihydroanthracenones as Inhibitors of Multiresistant Staphylococcus aureus

“…Further dimeric dihydroanthracene derivatives structurally related to 1 – 4 were previously reported from several higher plants including Bulbine abyssinica (Asphodelaceae), Cassia torosa, Cassia singueana, Cassia occidentalis (Fabaceae), Karwinskia humboldtiana and Karwinskia parvifolia (Rhamnaceae). , The biosynthesis of diverse natural products, originally only characterized from plants, by endophytic fungi has repeatedly been reported in the past decades. Well-known examples include paclitaxel, originally obtained from Taxus brevifolia and later reported from endophytic Taxomyces andreanae, and hypericin, reported from Hypericum perforatum and endophytic Thielavia subthermophila. ,− Hence, it is intriguing to speculate on the true origin of fungal dimeric dihydroanthracene derivatives such as those reported in this study based on the close structural resemblance of these natural products to known plant metabolites.…”

“…As both 3R and 3S configurations are reported for atrochrysone and torosachrysone monomers in the literature, 40−44 experiments to determine the central Further dimeric dihydroanthracene derivatives structurally related to 1−4 were previously reported from several higher plants including Bulbine abyssinica (Asphodelaceae), 45 Cassia torosa, 46 Cassia singueana, 47 Cassia occidentalis (Fabaceae), 48 Karwinskia humboldtiana 49 and Karwinskia parvifolia (Rhamnaceae). 50,51 The biosynthesis of diverse natural products, originally only characterized from plants, by endophytic fungi has repeatedly been reported in the past decades. Well-known examples include paclitaxel, originally obtained from Taxus brevifolia and later reported from endophytic Taxomyces andreanae, and hypericin, reported from Hypericum perforatum and endophytic Thielavia subthermophila.…”