RESUMO
Parasitic diseases continue to represent a threat on a global scale, particularly among the poorest countries in the world. This is particularly because of the absence of vaccines, and in some cases, resistance against available drugs, currently being used for their treatment. In this review emphasis is laid on natural products and scaffolds from African medicinal plants (AMPs) for lead drug discovery and possible further development of drugs for the treatment of parasitic diseases. In the discussion, emphasis has been laid on alkaloids, terpenoids, quinones, flavonoids and narrower compound classes of compounds with micromolar range activities against Schistosoma, Trypanosoma and Leishmania species. In each subparagraph, emphasis is laid on the compound subclasses with most promising in vitro and/or in vivo activities of plant extracts and isolated compounds. Suggestions for future drug development from African medicinal plants have also been provided. This review covering 167 references, including 82 compounds, provides information published within two decades (1997-2017).
RESUMO
The new cyclic heptapeptide unguisin F (1) and the known congener unguisin E (2), were obtained from the endophytic fungus Mucor irregularis, isolated from the medicinal plant Moringa stenopetala, collected in Cameroon. The structure of the new compound was unambiguously determined on the basis of one- and two-dimensional NMR spectroscopy as well as by high-resolution mass spectrometry. The absolute configuration of the amino acid residues of 1 and 2 was determined using Marfey's analysis. Compounds 1 and 2 were evaluated for their antibacterial and antifungal potential, but failed to display significant activities.