The UV-vis spectra of isocorydine 1, norisocorydine 2 and boldine 3 were studied in 2% v/v acetonitrile, at constant ionic strength (0.1 M NaCl, 35 degree Celsius). The pK(a) values of isocorydine 1 and norisocorydine 2 were 11.75 and 12.07, respectively. Boldine 3 gave a pK(a) value of 9.16 and 10.44. All of the alkaloids 1-3 were stable at physiological pH; thereby all of them will not ionize...

A new indole alkaloid, 12-hydroxy-N-acetyl-21(N)-dehydroplumeran-18-oic acid (13), and 11 known indole alkaloids: 3,4,5,6-tetradehydro-β-yohimbine (3), 19(E)-hunteracine (4), β-yohimbine (5), yohimbine (6), 19,20-dehydro-17-α-yohimbine (7), uleine (10), 20-epi-dasycarpidone (11), olivacine (8), 20-epi-N-nor-dasycarpidone (14), N-demethyluleine (15) and 20(E)-nor-subincanadine E (12) and a boone...

ETHNOPHARMACOLOGICAL RELEVANCE The West African tree Keetia leucantha (Rubiaceae) is used in traditional medicine in Benin to treat malaria. The twigs dichloromethane extract was previously shown to inhibit in vitro Plasmodium falciparum growth with no cytotoxicity (>100µg/ml on human normal fibroblasts). MATERIALS AND METHODS The dichloromethane and aqueous extracts of twigs of K. leucantha ...

The antiplasmodial activities of sixty norcantharidin analogs were tested in vitro against a chloroquine sensitive (D6, Sierra Leone) and chloroquine resistant (W2) strains of Plasmodium falciparum. Forty analogs returned IC(50) values <500 μM against at least one of the P. falciparum strains examined. The ring open compound 24 ((1S,4R)-3-(allylcarbamoyl)-7-oxabicyclo[2.2.1]heptane-2-carboxylic...

BACKGROUND The development of resistant to current antimalarial drugs is a major challenge in achieving malaria elimination status in many countries. Therefore there is a need for new antimalarial drugs. Medicinal plants have always been the major source for the search of new antimalarial drugs. The aim of this study was to screen selected Malaysian medicinal plants for their antiplasmodial pro...

A series of [(aryl)arylsufanylmethyl]pyridines (AASMP) have been synthesized. These compounds inhibited hemozoin formation, formed complexes (K(D) = 12 to 20 muM) with free heme (ferriprotoporphyrin IX) at a pH close to the pH of the parasite food vacuole, and exhibited antimalarial activity in vitro. The inhibition of hemozoin formation may develop oxidative stress in Plasmodium falciparum due...

Balanites rotundifolia (BR) (Van Tiegh.) Blatter (Balanitaceae) has been used in Ethiopian folk medicine to treat malaria, despite the lack of scientific validation. Therefore, the present study was carried out to evaluate the antiplasmodial activity of 80% methanol leaf extract of BR in mice. Both the 4-day suppressive test and Rane's test were employed. Three extract doses (BR100 mg/kg, BR200...

Morinda morindoides (Rubiaceae) is an indigenous tree of West Africa. This tree is used in Côte d’Ivoire against malaria. In this study, we investigated the in vitro antiplasmodial and antifungal activity of the leaves of M morindoides. M morindoides leaves were collected, air dried and made into a fine powder. Aqueous extracts (Aqe), ethanol (Eeth), ethyl acetate (EAc) and acetate-water (EAc-H...

The crude extract of the bark of Dehaasia longipedicellata exhibited antiplasmodial activity against the growth of Plasmodium falciparum K1 isolate (resistant strain). Phytochemical studies of the extract led to the isolation of six alkaloids: two morphinandienones, (+)-sebiferine (1) and (−)-milonine (2); two aporphines, (−)-boldine (3) and (−)-norboldine (4); one benzlyisoquinoline, (−)-retic...

A new series of potent potent aryl/alkylated (bis)urea- and (bis)thiourea polyamine analogues were synthesized and evaluated in vitro for their antiplasmodial activity. Altering the carbon backbone and terminal substituents increased the potency of analogues in the compound library 3-fold, with the most active compounds, 15 and 16, showing half-maximal inhibitory concentrations (IC50 values) of...