Search results for "bond"
showing 10 items of 3527 documents
Synthesis and characterisation of N-glycosyl amines from the reaction between 4,6-O-benzylidene-D-glucopyranose and substituted aromatic amines and a…
2001
Twelve N-glycosyl amines were synthesised using 4,6-O–benzylidene-D-glucopyranose and different substituted aromatic amines, including some diamines that resulted in bis-glycosyl amines. Another set of six N–glycosyl amines was synthesised using different hexoses and pentoses and 2–(o–aminophenyl)benzimidazole. All compounds were isolated as solid products and purified, their elemental compositions were established, and these were characterised by NMR (1H and 13C), UV–Vis, and FTIR spectroscopy, by FAB mass spectrometry (molecular-ion peaks gave molecular weights), and by their optical rotations. While the protected saccharide, 4,6-O-benzylidene-D-glucopyranose, exists as a mixture of β and…
Discovery of benzimidazole-based Leishmania mexicana cysteine protease CPB2.8ΔCTE inhibitors as potential therapeutics for leishmaniasis
2018
Abstract: Chemotherapy is currently the only effective approach to treat all forms of leishmaniasis. However, its effectiveness is severely limited due to high toxicity, long treatment length, drug resistance, or inadequate mode of administration. As a consequence, there is a need to identify new molecular scaffolds and targets as potential therapeutics for the treatment of this disease. We report a small series of 1,2‐substituted‐1H‐benzo[d]imidazole derivatives (9ad) showing affinity in the submicromolar range (Ki = 0.150.69 μM) toward Leishmania mexicanaCPB2.8ΔCTE, one of the more promising targets for antileishmanial drug design. The compounds confirmed activity in vitro against intrace…
Pimobendan B from powder diffraction data
2013
The title molecule, C19H18N4O2{systematic name: (RS)-6-[2-(4-methoxyphenyl)-1H-benzimidazol-5-yl]-5-methyl-4,5-dihydropyridazin-3(2H)-one}, adopts an extended conformation. The dihedral angles between the central benzimidazole ring sytem and the pendant methoxyphenyl and pyridazinone residues are 1.41 (18) and 9.7 (3)°, respectively. In the crystal, N—H...N hydrogen bonds link the imadazole groups into [001] chains, and pairs of N—H...O hydrogen bonds link the pyridazinone groups into dimers. Together, these generate a two-dimensional supramolecular structure parallel to (010). The layers are linked by C—H...π interactions.
Crystal structure of 5-(5,6-dihydrobenzo[4,5]imidazo[1,2-c]quinazolin-6-yl)-2-methoxyphenol
2015
In the molecule of the title compound, C21H17N3O2, the 5,6-dihydrobenzimidazo[1,2-c]quinazoline moiety is disordered over two orientations about a pseudo-mirror plane, with a refined occupancy ratio of 0.863 (2):0.137 (2). The dihedral angles formed by the benzimidazole ring system and the benzene ring of the quinazoline group are 14.28 (5) and 4.7 (3)° for the major and minor disorder components, respectively. An intramolecular O—H...O hydrogen bond is present. In the crystal, molecules are linked by O—H...N hydrogen bonds, forming chains running parallel to [10-1].
1,3-Dipolar cycloadditions of electrophilically activated benzonitrile N-oxides. Polar cycloaddition versus oxime formation.
2006
The reactions of electrophilically activated benzonitrile N-oxides (BNOs) toward 3-methylenephthalimidines (MPIs) have been studied using density functional theory (DFT) at the B3LYP/6-31G* level. For these reactions, two different channels allowing the formation of the [3 + 2] cycloadducts and two isomeric (E)- and (Z)-oximes have been characterized. The 1,3-dipolar cycloadditions take place along concerted but highly asynchronous transition states, while formation of the oximes is achieved through a stepwise mechanism involving zwitterionic intermediates. Both reactions are initiated by the nucleophilic attack of the methylene carbon of the MPIs to the carbon atom of the electrophilically…
Theoretical absorption and emission spectra of 1H- and 2H-benzotriazole
2003
Excitation energies, dipole moments, and transition properties for the lowest-lying 1(π, π*) and 1(n, π*) electronic states of two benzotriazole tautomers have been studied at the complete active space (CAS) SCF and multiconfigurational second-order perturbation (CASPT2) levels. With these results, the UV absorption spectra of 1H- and 2H-benzotriazole were first described individually, and then they were considered simultaneously in order to better understand the experimental, observed spectrum of benzotriazole. Aspects of the fluorescence of the compound have been also analyzed. The spectrum of benzotriazole is finally related to those of other azo-compounds.
1-Benzyl-1H-benzotriazole
2012
In the title compound, C13H11N3, the benzotriazole ring system is essentially planar, with a maximum deviation of 0.0173 (18) Å, and forms a dihedral angle of 75.08 (8)Å with the phenyl ring. In the crystal, pairs of weak C—H...N hydrogen bonds form inversion dimers. In addition, there are weak C—H...π(arene) interactions and weak π–π stacking interactions, with a centroid–centroid distance of 3.673 (11) Å.
1-Benzyl-1H-benzotriazole 3-oxide monohydrate
2012
In the title hydrate, C13H11N3O·H2O, the benzotriazole ring system is planar (r.m.s. deviation = 0.007 Å) and is almost orthogonal to the phenyl ring to which it is linked by a methylene group, forming a dihedral angle of 81.87 (15)°. In the crystal, molecules are linked into chains along [001] by O—H...O hydrogen bonds. The chains are consolidated into a three-dimensional architecture by C—H...O, C—H...π and π–π [centroid–centroid distance between the five- and six-membered rings of the benzotriazole ring system = 3.595 (3) Å] interactions.
1-Mesitylmethyl-1Hbenzotriazole 3-oxide.
2010
In the title compound, C16H17N3O, the benzotriazole ring forms a dihedral angle of 77.25 (6)° with the phenyl ring. The benzotriazole ring is essentially planar with a maximum deviation of 0.012 (19) Å. Weak intermolecular C—H...O hydrogen bonds form R22(10) motifs. The crystal packing is consolidated by π—π interactions with centroid–centroid distances of 3.5994 (12) Å together with very weak C—H...π interactions.
1-Benzyl-1H-benzotriazole 3-oxide-1-hy-droxy-1H-benzotriazole (1/1).
2012
In the title compound, C6H5N3O·C13H11N3O, the benzotriazole ring system in the 1-benzyl-1H-benzotriazole 3-oxide (A) molecule is close to being planar (r.m.s. deviation = 0.011 Å); its mean plane forms a dihedral angle of 67.56 (7)° with that of the attached phenyl ring. The benzotriazole ring system in the 1-hydroxybenzotriazole (B) molecule is also close to being planar (r.m.s. deviation = 0.010 Å). In the crystal, weak C—H...O and C—H...π interactions are present. TheAandBmolecules are linked by an O—H...N hydrogen bond.