The in vitro activity of root-tuber-peel extract of Flemingia vestita, an indigenous plant consumed by the natives in Northeast India, was tested against helminth parasites. Live parasites (nematode: Ascaris suum from pigs, A. lumbricoides from humans, Ascaridia galli and Heterakis gallinarum from domestic fowl; cestode: Raillietina echinobothrida from domestic fowl; trematode: Paramphistomum sp. from cattle) were collected in 0.9 % physiological buffered saline (PBS) and maintained at 37 +/- 1 degrees C. In vitro treatment of the parasites with the crude extract (50 mg/ml) in PBS revealed complete immobilization of the trematode and cestode in about 43 and 20 min, respectively. However, the cuticle-covered nematodes did not show any change in physical activity and remained viable even after a long period of exposure to the extract. Exposure of R. echinobothrida to genistein (0.5 mg/ml), an active principle isolated from the root-tuber peel, caused spontaneous loss of movement (paralysis) in 4.5 h, which was slower than the time required for praziquantel, the reference flukicide and cestodicide. The treated parasites showed structural alteration in their tegumental architecture. This study suggests the vermifugal activity of this plant extract against trematodes and cestodes.

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A facile, convenient, efficient, and high yielding synthesis of a combinatorial library of 3-aroylcoumarins has been developed by the condensation of easily available alpha-aroylketene dithioacetals (AKDTAs) and 2-hydroxybenzaldehydes (salicylaldehydes)/2-hydroxy-1-naphthaldehyde in the presence of catalytic amount of piperidine in THF reflux. The condensation of ferrocene derived alpha-aroylketene dithioacetal and 2-hydroxybenzaldehyde furnished coumarin installed on a ferrocene platform.

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Several di- and triarylfuran derivatives were prepared in high yields from but-2-ene-1,4-diones/but-2-yne-1,4-diones using formic acid in the presence of a catalytic amount of palladium on carbon and in poly(ethylene glycol)-200 medium in a one-pot operation under microwave irradiation (1-5 min).

A new fluorescent-cholesterol (Cum-Chl) molecule has been synthesized by attaching 3-acetyl-7-(diethylamino)-2H-chromen-2-one (Cum) to cholesterol via cholesterol bound β-keto ester. The β-keto ester was synthesized from the corresponding nitrile by applying the Blaise reaction. The molecule forms H-aggregates in solutions. The efficiency of aggregation is high in water. The H-aggregates are non-fluorescent in non-aqueous solvents but fluorescent in water. Aqueous bile salt media suppress the formation of H-aggregates, this effect being more pronounced for sodium deoxycholate (NaDC) which is more hydrophobic. With increasing bile salt concentration, the enhancement of monomeric fluorescence intensity of Cum-Chl generally follows the progressive miceller aggregation of bile salts. Incorporation of Cum-Chl into the dimyristoylphosphatidylcholine (DMPC) lipid bilayer membrane results in a significant enhancement of monomeric fluorescence intensity. The variation of fluorescence intensity is also sensitive to the thermotropic phase transition of the bilayer. It is seen that in such aqueous micro- and nanoscale organized media like bile salts and lipid bilayer membranes the monomer-to-aggregate fluorescence intensity ratio reflects the state of organization of the medium.