Search results for "Azole"

Substituent effects in nitro derivatives of carbazoles investigated by comparison of low-temperature crystallographic studies with density functional…

2014

The crystal structure of 9H-carbazole, C12H9N, (I), has been redetermined at low temperature for use as a reference structure in a comparative study with the structures of 1-nitro-9H-carbazole, C12H8N2O2, (II), and 9-nitrocarbazole, C12H8N2O2, (III). The molecule of (I) has crystallographically imposed mirror symmetry (Z′ = 0.5). All three solid-state structures are slightly nonplanar, the dihedral angles between the planes of the arene and pyrrole rings ranging from 0.40 (7)° in (III) to 1.82 (18)° in (II). Nevertheless, a density functional theory (DFT) study predicts completely planar conformations for the isolated molecules. To estimate the influence of nitro-group substitution on aroma…

Crystal structure of (2R*,3aR*)-2-phenylsulfonyl-2,3,3a,4,5,6-hexahydropyrrolo[1,2-b]isoxazole

2017

The title compound, C12H15NO3S, was prepared by 1,3-dipolar cycloaddition of 3,4-dihydro-2H-pyrrole 1-oxide and phenyl vinyl sulfone. In the molecule, both fused five-membered rings display a twisted conformation. In the crystal, C—H...O hydrogen bonds link neighbouring molecules, forming chains running parallel to thebaxis.

Crystal structure, spectroscopic characterization and Hirshfeld surface analysis of trans-di­aqua­[2,5-bis­(pyridin-4-yl)-1,3,4-oxa­diazole]di­thio­c…

2019

The NiII atom in the mononuclear title complex has an almost regular octa­hedral N4O2 coordination geometry. In the crystal, the complex mol­ecules are linked in a three-dimensional network through strong O—H⋯N hydrogen bonds.

4-cyanopirazoles derivatives as a new class of compounds with potent antifungal activity

2015

Introduction We have reported that some 4-nitrosopyrazoles derivatives displayed in vitro and in vivo potent antifungal activity at no cytotoxic concentration and some of these compounds were 4 times more potent than Amphotericine B and Fluconazole respectively against Cryptococcus Neoformans and C. Krusei. We reported also that the absence of NO group or its replacement with NO2 or NH2 groups gave compounds devoid of antimycotical activity. Aim of the work To better understand the mechanism of action and with the aim of identifying the chemical features responsible for the action, we synthesized and tested a new class of compounds in which the 4-NO group was replaced with 4-CN group having…

Mononuclear rearrangements of heterocycles in water/β-CD: information on the real site of reaction from structural modifications of substrates and fr…

2007

Abstract The effect of β-cyclodextrin (β-CD) on the reactivity in the base-catalyzed pathway for the rearrangement in water of some ( Z )-hydrazones of 3-benzoyl-1,2,4-oxadiazoles ( 1b – f ) into the relevant triazoles ( 2b – f ) was investigated, finding different behavior as a function of the proton concentration. ESIMS and 1 H NMR data evidence the formation of host – guest complexes. The whole of the experimental and calculated (MM2) data enabled us to draw some intriguing conclusions concerning the influence of the structures of the substrates and the nature of the formed host – guest complexes on the real site of the reaction.

Metronidazole/montmorillonite nanodevices for controlled drug delivery

2014

Spectroscopic characterization and biological activity ofL-methionyl-L histidinato complexes of R2Sn(IV) ions (R?=?Me, nBu, Ph) and X-ray structure o…

2000

Complexes of L-methionyl-L-histidine (H2MetHis) with R2Sn(IV) ions (R = Me, nBu, Ph) have been synthesized. The crystal and molecular structures of Me2SnMetHis·0.5MeOH have been determined by X-ray diffraction. The title compound contains two crystallographically independent molecular units possessing the same trigonal-bipyramidal geometry at tin, each dimethyltin(IV) moiety being coordinated by the terminal amino nitrogen, deprotonated peptide nitrogen and terminal carboxylate group, neither the imidazole nor thioether groups being involved in bonding. IR spectroscopy was used to probe the structure of the complexes in the solid state, and the structure in solution (CD3OD) was assessed by …

Theoretical study of selective H3 receptor antagonists of histamine

1993

Abstract The conformations and charge distributions of three selective H3 receptor antagonists of histamine were determined using the MNDO approach. The results suggest that the conformational flexibilities of betahistine, N α-(2-phenylacetyl)histamine and thioperamide are different; however, the low-energy conformations of these compounds show closely related spatial orderings. The MNDO calculations predict a significant population of the N1H form in the imidazole systems of N α-(2-phenylacetyl)histamine and thioperamide. Our results indicate that the conformational behaviour of H3 antagonists is closely similar to that reported for H2 antagonists of histamine. These results emphasize the …

Vulvar involvement in pediatric Crohn’s disease: a systematic review

2018

Purpose: The aim of the study is to report a systematic review (from 2000 to 2017) of all pediatric cases of vulvar Crohn’s disease (VCD) and to highlight the key-points for a correct diagnosis and management of this rare condition. Methods: An electronic search using the Pubmed/Medline, Scopus, EMBASE, Cochrane database and Google Scholar database was performed according to PRISMA guidelines. Results: Twenty pediatric studies and 22 cases of VCD were included for analysis. All the articles reported a single case, except two articles where two cases, respectively, are described. Clinical vulvar examination showed the following main manifestations: vulvar erythema (9/22 cases, 40.9%), vulv…

Synthesis and Antiproliferative Activity of 2,5-bis(3′-Indolyl)pyrroles, Analogues of the Marine Alkaloid Nortopsentin

2013

2,5-bis(3′-Indolyl)pyrroles, analogues of the marine alkaloid nortopsentin, were conveniently prepared through a three step procedure in good overall yields. Derivatives 1a and 1b exhibited concentration-dependent antitumor activity towards a panel of 42 human tumor cell lines with mean IC50 values of 1.54 μM and 0.67 μM, respectively. Investigating human tumor xenografts in an ex-vivo clonogenic assay revealed selective antitumor activity, whereas sensitive tumor models were scattered among various tumor histotypes.