Planta Med 2006; 72 - P_032
DOI: 10.1055/s-2006-949832

Alkaloids from Phaedranassa dubia (Amaryllidaceae). In vitro antiprotozoal activity

E Osorio 1, 2, R Brun 3, F Viladomat 2, C Codina 2, F Cabezas 4, J Bastida 2
  • 1Grupo de Investigación en Sustancias Bioactivas, Facultad de Farmacia, Universidad de Antioquia, A.A. 1226-Medellín, Colombia
  • 2Departament de Productes Naturals, Facultat de Farmàcia, Universitat de Barcelona, Avda Diagonal 643, 08028-Barcelona, Spain
  • 3Parasite Chemotherapy, Swiss Tropical Institute, Socinstraβe 57, CH-4002 Basel, Switzerland
  • 4Departamento de Química, Grupo de Química de Compuestos Bioactivos, Universidad del Cauca, Popayán, Colombia

Continuing our work on Amaryllidaceae alkaloids, the bulbs of Phaedranassa dubia (H.B. & K.) were studied and found to contain eight alkaloids: pseudolycorine (1), ungeremine (2), zefbetaine (3), haemanthamine (4), sanguinine (5), galanthamine (6), epinorgalanthamine (7) and buphanamine (8). Their structures were established using physical and spectroscopic methods. Each alkaloid was tested against the following parasitic protozoa: Trypanosoma brucei rhodesiense, Trypanosoma cruzi, Leishmania donovani and Plasmodium falciparum. The results showed a good activity of the betaine ungeremine against P. falciparum (IC50=0.09µg/mL). Additionally, haemanthamine presented noteworthy activity against T. brucei rhodesiense (IC50=0.49µg/mL) and P. falciparum (IC50=0.69µg/mL) and pseudolycorine was active against P. falciparum (IC50=0.24µg/mL).

(1)
(2): R1 + R2 =CH2
(4
(5): R1=OH, R2=R4 =H, R3=Me
(8)
(3): R1=H, R2=Me
(6): R1=OH, R2=H, R3=R4=Me
(7): R1=R3=H, R2=OH, R4=Me

Acknowledgements: Edison Osorio thanks the Fundación Carolina for his doctoral fellowship.