Angeloylated Germacranolides from Daucus virgatus and Their Plasmodium Transmission Blocking Activity

Abstract

Phytochemical investigation of the aerial parts of the Tunisian plant Daucus virgatus led to the isolation of eight new germacranolides named daucovirgolides A-H (1-8). The stereostructures of these sesquiterpene lactones, decorated by either one or two angeloyl groups, have been determined by a combination of MS, NMR spectroscopy, chemical derivatization, and comparison of experimental electronic circular dichroism curves with TDDFT-predicted data. Daucovirgolide G (7) proved to be the single member of this family to possess a marked inhibitory activity (92% at 50 μg/mL) on the development of Plasmodium early sporogonic stages, the nonpathogenic transmissible stages of malaria parasites, devoid of general cytotoxicity. The selective activity of daucovirgolide G points to the existence of strict structural requirements for this transmission-blocking activity and therefore of a well-defined, although yet unidentified, biological target.

Inhibitory effects of cynaropicrin on human melanoma progression by targeting MAPK, NF‐κB, and Nrf‐2 signaling pathways in vitro

“…detonsa as reported (Formisano et al, 2017a). Vernodalol and vernolide were obtained from Vernonia amygdalina as reported (Sinisi et al, 2015). Daucovirgolides B, G, and F were obtained from Daucus virgatus as reported (Sirignano et al, 2017).…”

“…The compounds included in the library belong to different structural classes and possess different acyl decorations on the sesquiterpene core. In particular, we have selected vernolide and vernodalol, obtained from Vernonia amygdalina (Sinisi et al, 2015), centaurea lactone, and cynaropicrin, obtained from aerial parts of Centaurea drabifolia subsp. detonsa (Bornm) Wagenitz (Formisano et al, 2017a), a plant endemic of Turkey, very popular to prepare infusions to be used both as refreshing drink and as traditional remedy with antiinflammatory applications (Honda et al, 1996).…”

“…detonsa (Bornm) Wagenitz (Formisano et al, 2017a), a plant endemic of Turkey, very popular to prepare infusions to be used both as refreshing drink and as traditional remedy with antiinflammatory applications (Honda et al, 1996). Daucovirgolides B, G, and F have been obtained from Daucus virgatus (Sirignano et al, 2017); hydroxytigloyldeacylaguerin (HTDA), acydehydromelitensin (ADM), onopordopicrin, and elemacarmanin from Onopordon illyricum (Formisano et al, 2017b). These compounds belong to the guaianolide, germacranolide, and elemanolide structural classes.…”

Natural Products: A Potential Source of Malaria Transmission Blocking Drugs?

“…From Vernonia amygdalina (Asteraceae), two sesquiterpene lactones were isolated, vernodalol and vernolide, with both showing only marginal ESS activity (Figure 3, Table 2, Table S1) [77]. A germacranolide sesquiterpene lactone from Daucus virgatus (Apiaceae), daucovirgolides G, was the only compound with marked potency in vitro, strongly inhibiting ESS development ( Figure 3, Table 2, Table S1) [78,79].…”

Chemical Constituents of the Aerial Parts ofDaucus carotasubsp.hispidusGrowing in Tunisia

“…7 Besides, terpenoids are cited as the most widespread class of secondary metabolites in D. carota and other Daucus species. 8 Due to the wide variety of their biological activities, the number of research studies focused on new terpenoids isolation has grown. Within this context and as a part of our ongoing phytochemical and biological investigations of crude extracts from Tunisian medicinal plants, our interest in the discovery of new bioactive constituents prompted us to initiate, and for the first time in this study, the phytochemical and biological investigations of the dichloromethane extract from D. carota subsp.…”