New imidazole-based compounds active against Trypanosoma cruzi

Background: Current drugs available for the treatment of Chagas disease are fraught with several challenges including severe toxicity and limited efficacy. These factors coupled with the absence of effective drugs for treating the chronic stage of the disease have rendered the development of new drugs against Chagas disease a priority. Objective: This study screened several imidazole-based compounds for anti-Trypanosoma potential. Method: Using an in vitro experimental infection model, several imidazole-based compounds were screened for anti-proliferative effect on Trypanosoma cruzi epimastigotes. Additionally, all test compounds were evaluated for unspecific cytotoxicity on L929 murine fibroblasts. Benznidazole (BZN) served as reference drug. Results: All test compounds demonstrated interesting trypanocidal potential with IC values in the μM range (1 9.42). Conclusion: We provide evidence which implicate the imidazole-based compounds as potential prototypes for the development of anti-parasitic agents. Findings have far-reaching relevance to drug discovery efforts for trypanosomiasis.Peer Reviewe

One-pot syntheses of pseudopteroxazoles from pseudopterosins : a rapid route to non-natural congeners with improved antimicrobial activity

Rapid one-pot methodologies to prepare pseudopteroxazole (1) and novel congeners from abundant natural pseudopterosins have been devised. This is highlighted here with the first synthesis of the marine natural product homopseudopteroxazole (2) utilizing a novel, silver(I)-mediated catechol to benzoxazole transformation. Pseudopteroxazoles and isopseudopteroxazoles exhibit potent activity against a range of important Gram-positive pathogens including Mycobacterium spp. and vancomycin-resistant Enterococcus faecium. Several non-natural pseudopteroxazoles exhibited strong activity against methicillin-resistant Staphylococcus aureus, thereby displaying a broader spectrum of antibiotic activity compared to pseudopteroxazole

Synthesis, characterization and ethylene polymerization behavior of 8-(nitroarylamino)-5,6,7-trihydroquinolylnickel dichlorides: Influence of the nitro group and impurities on catalytic activity

The series of N-(5,6,7-trihydroquinolin-8-ylidene)nitroarylamine ligands (L1-L4) was prepared and used to synthesize the chloro-bridged dinickel complexes (Ni1-Ni4) and the bis-ligated mononickel(II) complex (Ni5) in good yield. Molecular structures of Ni1, Ni2, Ni4, and Ni5 were confirmed by single-crystal X-ray diffraction analysis, revealing a pseudosquare-pyramidal geometry around nickel in the chloro-bridged complexes (Ni1, Ni2, and Ni4) and a distorted octahedral geometry at the nickel atom in the bis-ligated complex (Ni5). Upon treatment with ethylaluminum sesquichloride (EASC, Et 3Al2Cl3) or methylaluminoxane (MAO), all nickel complexes exhibited high activities (up to 4.05 × 106 g (PE) mol-1 h-1) for ethylene polymerization. Moreover, heterocyclic impurities such as tetrahydrofuran (THF) and pyridine, often detected in common solvents, were added to the catalytic system of precatalyst Ni2 under controlled conditions and were found to have a negative influence on the catalytic behavior during ethylene polymerization. © 2011 American Chemical Society