Our previously synthesized 37 compounds, which are 2,5,6-substituted benzoxazole, benzimidazole, benzothiazole, and oxazolo(4,5-b)pyridine derivatives, were tested for their eukaryotic DNA topoisomerase II inhibitory activity in cell free system and 28 were found to inhibit the topoisomerase II at an initial concentration of 100 microg/ml. After further testing at a lower range of concentration...

The asymmetric unit of the title compound, C(8)H(5)F(3)N(2), consists of two half-mol-ecules, one lies on a mirror plane and the other is generated by twofold rotation symmetry, with the axis running through the trifluoro-methyl C atom and the attached benzimidazole C atom. The two 2-trifluoro-methyl-1H-benzimidazole mol-ecules are connected by N-H⋯N hydrogen bonds involving the disordered NH H...

Twenty analogues of pentamidine, 7 primary metabolites of pentamidine, and 30 dicationic substituted bis-benzimidazoles were screened for their inhibitory and fungicidal activities against Candida albicans and Cryptococcus neoformans. A majority of the compounds had MICs at which 80% of the strains were inhibited (MIC80s) comparable to those of amphotericin B and fluconazole. Unlike fluconazole...

The first example of DAST-promoted Beckmann rearrangement/intramolecular cyclization of acyclic ketoximes is described. This unique protocol represents a direct and effective pathway to 2-oxazolines, benzimidazoles and benzoxazoles in moderate to good yields.

A bicyclic guanidine-catalyzed Michael addition of 3-benzyl substituted oxindoles to N-maleimides has been developed to produce oxindole derivatives with a quaternary carbon chiral center at the 3-position in excellent yields and enantio- and diastereoselectivities. This is the first incorporation of N-benzylic α-branched succinimides into 3,3-disubstituted oxindoles.

Iridium-catalyzed acceptorless dehydrogenative coupling of tertiary amines and arylamines has been developed. A number of benzimidazoles were prepared in good yields. An iridium-mediated C-H activation mechanism is suggested. This finding represents a novel strategy for the synthesis of benzimidazoles.

A series of tetrazole derivatives (3a-h) were synthesized and screened for antioxidant activity by nitric oxide free radical scavenging activity. All the synthesized compounds were structurally elucidated by spectral techniques such as IR, H NMR spectroscopy and mass spectrometry. The compounds 3b, 3d 3f and 3h exhibited promising antioxidant activities which were found to be comparable with st...