Synthesis and antiprotozoal activity of novel 1-methylbenzimidazole derivatives.

In this paper are reported the synthesis and antiprotozoal activity in vitro of 24 1-methylbenzimidazole derivatives (13-36) substituted at position 2 with aminocarbonyl, N-methylaminocarbonyl, N,N-dimethylaminocarbonyl, ethoxycarbonyl, 1-hydroxyethyl and acetyl groups, some of them with chlorine atoms at the benzenoid ring. Compounds 13-36 were more active than metronidazole, the choice drug against Giardia intestinalis and most of them against Trichomonas vaginalis. The most active group of compounds for both parasites was that with a 2-ethoxycarbonyl group (16, 22, 28, 34), independently of the substitution pattern at the benzenoid ring.

Effect of Mexican medicinal plant used to treat trichomoniasis on Trichomonas vaginalis trophozoites.

Crude methanolic extracts from 22 Mexican medicinal plants were screened for antitrichomonal activity against Trichomonas vaginalis, which is the etiological agent of trichomoniasis. Among the plants tested Carica papaya and Cocos nucifera showed the best antitrichomonal activity with IC(50) values of 5.6 and 5.

Antiprotozoal properties of Helianthemum glomeratum.

Structure characterization and biological evaluation of the compounds isolated from Helianthemum glomeratum, particularly that of the polyphenols, has been the aim of a series of studies carried out to define the further potential use of this plant in the treatment of infectious diarrhoea in children. The flavan-3-ols, (-)-epigallocatechin and (-)-epigallocatechin gallate, isolated from Helianthemum glomeratum roots were tested for their antiamoebic and antigiardial effects in vitro. Compared with the activity determined with the leaf and the root methanol extracts, the effect of (-)-epigallocatechin against Entamoeba histolytica was of a similar potency, nevertheless, it also suppressed the growth of Giardia lamblia in axenic cultures, a parasite that proved to be resistant to the crude extracts.