1-benzyl-2-phenylbenzimidazole and benzimidazole

A library of eighty-six assorted benzimidazole derivatives was screened for antiviral activity against a panel of ten RNA and DNA viruses. Fifty-two of them displayed different levels of activity against one or more viruses, among which CVB-5, RSV, BVDV and Sb-1 were the most frequently affected. In particular, fourteen compounds exhibited an EC50 in the range 9-17μM (SI from 6 to >11) versus CVB-5, and seven compounds showed an EC50 in the range 5-15μM (SI from 6.7 to ⩾20) against RSV, thus resulting comparable to or more potent than the respective reference drugs (NM108 and ribavirin). Most of these compounds derive from 2-benzylbenzimidazole, but also other molecular scaffolds [as 1-phenylbenzimidazole (2), 2-trifluoromethylbenzimidazole (69), dihydropyrido[3',2':4,5]imidazo[1,2-a][1,4]benzodiazepin-5-one (3), dibenzo[c,e]benzimidazo[1,2-a]azepine (22), and 2-(tetrahydropyran-2-yl)benzimidazole (81, 82 and 86)] are related to interesting levels of activity against these or other viruses (BVDV, Sb-1). Thus, these scaffolds (some of which, so far unexplored), represent valid starting points to develop more efficient agents against pathologies caused by CVB-5, RSV, BVDV and Sb-1 viruses.

Topics: Animals; Antiviral Agents; Benzimidazoles; Cattle; Cell Line; Cell Proliferation; Cell Survival; Chlorocebus aethiops; Cricetinae; Dose-Response Relationship, Drug; Enterovirus; Humans; Microbial Sensitivity Tests; Molecular Structure; Poliovirus; Respiratory Syncytial Viruses; Structure-Activity Relationship; Vero Cells; Virus Replication

2-Aryl-1-arylmethyl-1H-benzimidazole derivatives having different side chains on the structure were examined in vitro for their antioxidant abilities by 2,2-diphenyl-1-picryl hydrazine radical scavenging activity, reducing ability, OH radical scavenging activity, inhibition of polyphenol oxidase and xanthine oxidase. Overall, with few exceptions, all the 2-aryl-1-arylmethyl-1H-benzimidazoles showed moderate biological activity with all parameters examined. The 2-aryl-1-arylmethyl-1H-benzimidazoles were found to be reactive toward 2,2-diphenyl-1-picryl hydrazine radical and had considerable reducing ability, with significant xanthine oxidase inhibition. With few exceptions, all the compounds under study were found to possess moderate-to-poor OH radical scavenging activity and inhibited polyphenol oxidase significantly. These findings suggest that these 2-aryl-1-arylmethyl-1H-benzimidazoles can be considered as potential antioxidant and xanthine oxidase inhibitory agents, those might be further, explored for the design of lead antioxidant and antigout drug candidates using in vivo trials.

Topics: Animals; Antioxidants; Benzimidazoles; Biphenyl Compounds; Catechol Oxidase; Cattle; Enzyme Inhibitors; Hydroxyl Radical; Milk; Picrates; Protein Binding; Xanthine Oxidase

Present communication deals with the in vitro time point quantitative antibacterial evaluation of newly synthesized 1,2-disubstituted benzimidazoles (3a-p) and 2-substituted benzothiazoles (5a-h) against Gram-positive bacteria Staphylococcus aureus, Bacillus cereus, and Gram-negative bacteria Vibrio cholerae, Shigella dysenteriae and Escherichia coli. These compounds were synthesized under mild reaction conditions using Al(2)O(3)-Fe(2)O(3) nanocrystals as heterogeneous catalyst. Bio-evaluation studies revealed that, compounds 3a, 5a and 5d exhibited moderate to good antibacterial activity against all the tested bacterial stains. The compounds 3a, 3f and 5a have shown enhanced inhibitory activity compared with standard antibacterial drug ciprofloxacin against V. cholerae, B. cereus, and S. dysenteriae, respectively. Additionally, the compounds 3a, 3e, 3f, 3h and 5b displayed complete bactericidal activity within 24 h, whereas ciprofloxacin took 48 h to kill those bacteria completely.

Topics: Aluminum Oxide; Anti-Bacterial Agents; Benzimidazoles; Benzothiazoles; Catalysis; Ferric Compounds; Gram-Negative Bacteria; Gram-Positive Bacteria; Microbial Sensitivity Tests