title: Synthesis and antimalarial activity of semicarbazone and thiosemicarbazone derivatives.
abstract: Seventeen semicarbazone and thiosemicarbazone derivatives were prepared and tested in vitro against a chloroquine resistant strain of Plasmodium falciparum (W2) to evaluate their antiplasmodial potential. Three thiosemicarbazones were found to be active against the parasite and non-toxic to human peripheral blood mononuclear cells (PBMC). Among these, compound 5b presented the lowest IC50 value against P. falciparum (7.2 microM) and was the least toxic in the PBMC proliferation assay (IC50=73.5 microM). It was selected for in vivo tests on mice infected with Plasmodium berghei (strain NK-65). The thiosemicarbazone 5b was able to reduce the parasitaemia by 61% at 20 mg/kg on day 7 after infection without any sign of toxicity to the animals. In comparison, the standard drug chloroquine at 15 mg/kg showed a reduction around 95%. These in vitro and in vivo results make 5b an interesting lead for further development.
authors.affiliation: Laboratório de Química de Produtos Naturais, Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz. Av. Augusto de Lima 1715, 30190-002, Belo Horizonte, MG, Brazil.
authors.forename: Renata B
authors.initials: RB
authors.lastname: de Oliveira
authors.forename: Elaine M
authors.initials: EM
authors.lastname: de Souza-Fagundes
authors.forename: Rodrigo P P
authors.initials: RP
authors.lastname: Soares
authors.forename: Anderson A
authors.initials: AA
authors.lastname: Andrade
authors.forename: Antoniana U
authors.initials: AU
authors.lastname: Krettli
authors.forename: Carlos L
authors.initials: CL
authors.lastname: Zani
mesh_terms: D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D006801:Humans; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects; D008288:Malaria / Q000188:drug therapy; D051379:Mice; D010963:Plasmodium falciparum / Q000187:drug effects; D012664:Semicarbazones / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D013882:Thiosemicarbazones / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use
chemical_list: D012664:Semicarbazones; D013882:Thiosemicarbazones