RESUMO
Five known (1, 2, 4, 6 and 7) halogenated monoterpenes together with 1Z,3R∗,4S∗,5E,7Z)-1-bromo-3,4,8-trichloro-7-(dichloromethyl)-3-methylocta-1,5,7-triene (3) and (3R∗,4S∗)-3,4,6,7-tetrachloro-3,7-dimethyl-octen-1-ene (5) were isolated from the red macroalga Plocamium suhrii and their structures deduced from their spectroscopic data. The seven compounds from P. suhrii together with five related compounds from Plocamium cornutum have been evaluated for their cytotoxic effects on an esophageal cancer cell line (WHCO1). Compounds 1-6 showed greater cytotoxicity in this assay as compared to the known anticancer drug cisplatin.
Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Neoplasias Esofágicas/tratamento farmacológico , Hidrocarbonetos Halogenados/isolamento & purificação , Hidrocarbonetos Halogenados/farmacologia , Monoterpenos/isolamento & purificação , Monoterpenos/farmacologia , Plocamium/química , Antineoplásicos Fitogênicos/química , Cisplatino/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Hidrocarbonetos Halogenados/química , Estrutura Molecular , Monoterpenos/química , África do SulRESUMO
In our continuing search for antimalarial leads from South African marine organisms we have examined the antiplasmodial organic extracts of the endemic marine red alga Plocamium cornutum (Turner) Harvey. Two new and three known halogenated monoterpenes were isolated and their structures determined by standard spectroscopic techniques. The 3,7-dimethyl-3,4-dichloro-octa-1,5,7-triene skeleton is common to all five compounds. Interestingly, compounds bearing the 7-dichloromethyl substituent showed significantly higher antiplasmodial activity toward a chloroquine sensitive strain of Plasmodium falciparum.
Assuntos
Antimaláricos/isolamento & purificação , Halogênios/química , Monoterpenos/isolamento & purificação , Extratos Vegetais/química , Plasmodium falciparum/efeitos dos fármacos , Plocamium/química , Animais , Antimaláricos/química , Antimaláricos/farmacologia , Espectroscopia de Ressonância Magnética , Monoterpenos/química , Monoterpenos/farmacologia , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Espectrofotometria UltravioletaRESUMO
In the course of our search for antimalarial leads from marine algae, four metabolites, sargaquinoic acid, sargahydroquinoic acid, sargaquinal and fucoxanthin, were isolated from the South African alga Sargassum heterophyllum. Fucoxanthin and sargaquinal showed good antiplasmodial activity toward a chloroquine-sensitive strain (D10) of Plasmodium falciparum (IC50 1.5 and 2.0 microM, respectively), while sargaquinoic acid and sargahydroquinoic acid were only moderately active (IC50 12.0 and 15.2 microM, respectively).
