Bis-alkylquinolines 1-6 were synthetized via Williamson reaction between 8-hydroxyquinaldine with different É, ù-dihaloalkanes. Structures of all the products were elucidated by spectroscopic analysis. Cytotoxic and antileishmanial activities of synthesized compounds were determinated on U-937 cells and L. (V) panamensis amastigotes, respectively. Compound 5, 1,9-bis[(2-methylquinolin-8-yl)oxy]nonane, was the most selective against axenic and intracellular amastigotes (EC50 = 11.3 and 22.6, ìg/mL), with selectivity indices greater than 17.7 and 8.8, respectively; which makes this compound promising for the developing of new leishmanicidal drugs.

Steroids from Solanum nudum (SNs) have demonstrated antiplasmodial activity against erythrocytic stages of the Plasmodium falciparum strain FCB-2. It is well known that steroids can alter the membrane function of erythrocytes. Thus, we assessed alterations in the membranes of uninfected red blood cells, the parasite invasiveness and the solute-induced lysis of parasitised red blood cells (pRBCs). induced by SNs. We found that most merozoites were unable to invade SN-treated erythrocytes. However, transmission electron microscopy revealed no effect on the morphology of uninfected erythrocytes treated with either SN2 or diosgenone and neither SN induced haemolysis of uninfected erythrocytes. SN2 and SN4 inhibited isosmotic sorbitol and alanine-induced haemolysis of pRBCs. In contrast, diosgenone and SN1 did not inhibit solute-induced haemolysis. The inhibition of solute-induced lysis of parasitised erythrocytes by SN2 and SN4 suggest an action of these SNs on new permeability pathways of pRBCs.

En este trabajo se evalúa la actividad antioxidante (Φ), definida como la pendiente de la regresión simple lineal de f o /f i contra la concentración µM, en un modelo de inhibición de la peroxidación lipídica de mantequilla a 60ºC, donde fi es el efecto de cada concentración del isoespintanol y fo es el control. Se encuentra que la formación de hidroperóxidos (valor de peróxido PV) y las especies mas oxidadas reactivas al ácido tiobarbiturico (TBARS) fueron retardadas de manera similar por el isoespintanol (ΦTBARS=9.46x10-5 ± 1.33x10-5 y ΦPV = 9.41x10-5 ± 1.62x10-5). De igual manera, el butilhidroxi tolueno y el isoespintanol inhiben el proceso oxidativo de mantequilla en un 28.0 y 23.3 % a concentraciones de 2380.9 y 3809.5 µM respectivamente.

The antioxidant activity (Φ) is defined as the slope of the simple linear regression of f0/f i against the concentration µM, in an inhibition model of lipid peroxidation of butter at 60° C, where f i is the concentration effect of isoespintanol and f0 is the control. It is found that the formation of: hydroperoxides (peroxide value of PV) and the most oxidized species reactive to thiobarbituric acid (TBARS), were similarly delayed by isoespintanol (ΦTBARS = 9.46x10-5 ± 1.33x10-5 and ΦPV = 9.41x10-5 ± 1.62x10-5). Likewise, the butilhidroxy toluene and isoespintanol inhibit the oxidative process of butter in a 28.0 and 23.3% at concentrations of 2380.9 and 3809.5 µ M respectively.

The leaves of Duguetia vallicola, a fairly common, large evergreen tree from the coastal regions of Panama, Colombia and Venezuela, contain (6aS)-glaziovine (1) as a major constituent. The abundance and renewable character of the plant material make it an attractive source for this rare, psychoactive alkaloid. The availability of glaziovine and its O-methyl derivative pronuciferine (2) has made complete ¹H and 13C NMR assignments of proaporphines possible for the first time