Structure-activity relationships of a new antifungal imidazole, AFK-108, and related compounds

Antibacterial activity of vinyl imidazole(vi) functionalized silica polymer nanocomposites (SBA/VI) against Gram negative and Gram positive bacteria

Vinyl imidazole functionalized mesoporous silica (SBA/VI) nanocomposites for antibacterial activity.

Chemoenzymatic synthesis and biological evaluation of enantiomerically enriched 1-(β-hydroxypropyl)imidazolium- and triazolium-based ionic liquids

Racemic 1-(β-hydroxypropyl)azoles were prepared by solvent-free direct regioselective ring opening of 1,2-propylene oxide with imidazole or 1,2,4-triazole. Lipase-catalyzed transesterification of alcohols with vinyl acetate resulted in kinetic enantiomers resolution. Separated (S)-enantiomers of (+)-1-(1H-imidazol-1-yl)propan-2-ol and (+)-1-(1H-1,2,4-triazol-1-yl)propan-2-ol were quaternized with alkyl bromides or iodides, yielding novel optically active ionic liquids. Racemic salts were tested against a wide range of microorganisms.

1,2,4,5-Tetra-phenyl-1H-imidazole

The asymmetric unit of the title compound, C₂₇H₂₀N₂, contains two independent mol­ecules, A and B. In both mol­ecules, the N atom in the 1-position and the C atom in the 5-position are statistically disordered [as 0.571 (8):0.429 (8) in A and 0.736 (9):0.264 (9) in B]. The phenyl rings in the 1-, 2-, 4- and 5-positions in A are twisted from the central imidazole ring by 84.3 (2), 21.6 (2), 21.5 (2) and 75.7 (2)°, respectively. The corresponding dihedral angles in B are 85.5 (2), 3.8 (2), 2.4 (2) and 81.7 (2)°, respectively.

1-{4-Chloro-2-[2-(2-fluoro-phen-yl)-1,3-dithio-lan-2-yl]phen-yl}-2-methyl-1H-imidazole-5-carbaldehyde

There are two mol­ecules in the asymmetric unit of the title imidazole derivative, C₂₀H₁₆ClFN₂OS₂. In one mol­ecule, the dithiol­ane ring is disordered over two positions in a 0.849 (9):0.151 (10) ratio. The imidazole ring makes dihedral angles of 79.56 (9) and 18.45 (9)° with the 4-chloro­phenyl and 2-fluoro­phenyl rings, respectively, in one mol­ecule; in the other mol­ecule, the corresponding angles are 82.72 (9) and 17.39 (10)°. In the crystal, mol­ecules are linked by weak C—H⋯O inter­actions and these linked mol­ecules are stacked along the b axis by π–π inter­actions with a centroid–centroid distance of 3.4922 (11) Å. In addition, π–π inter­actions between the imidazole and 2-fluoro­phenyl rings are also observed, with centroid–centroid distances of 3.4867 (11) and 3.4326 (10) Å. The crystal is further consolidated by weak C—H⋯π inter­actions. Cl⋯S [3.5185 (8) Å], C⋯O [3.192 (3) Å] and C⋯C [3.326 (2)–3.393 (3) Å] short contacts are also observed.

Identification and complementation of abnormal hyphal branch mutants ahbA1 and ahbB1 in Aspergillus nidulans

Branching generates new axes of polar growth in filamentous fungi and is critical for development, reproduction, and pathogenicity. To investigate branching we screened an Aspergillus nidulans temperature-sensitive mutant collection for abnormal hyphal branch (ahb) mutants. We identified two mutants, ahbA1, which showed reduced branching relative to wild type at restrictive temperature, and ahbB1, which showed increased branching relative to wild type at restrictive temperature. Both mutants also showed abnormal conidiophore development at restrictive temperature. The ahbA1 hypobranching mutant showed defects in nuclear division and hydroxyurea resistance. Complementation and sequencing showed that ahbA1 is a previously identified allele of the cell cycle regulator nimX. The ahbB1 hyperbranching mutant had an increased number of nuclei, was osmotically remedial and Calcofluor resistant. The ahbB gene is predicted to encode a novel protein that has homologues exclusively in filamentous fungi. The C-terminal domain of the predicted AhbB protein showed homology with the heme-binding domain of a cytochrome P450 protein and sequencing of the ahbB1 mutant allele showed that the lesion lies just before this putative heme-binding domain. The ahbB1 mutant showed increased sensitivity to the ergosterol biosynthesis inhibitor imidazole. Our results suggest a link between nuclear division and branching and a possible role for membrane synthesis in branching.

Design and synthesis of novel imidazole derivatives as potent inhibitors of allene oxide synthase(CYP74)

Allene oxide synthase (AOS) is a key enzyme in the oxylipin pathway in plants leading to jasmonic acid and other jasmonates (JAs), important signal mediators of defense signal networks in plants. AOS uses hydroperoxylinolenic acid as an oxygen donor as well as the substrate, thus the biochemical conversion of 13(S)-hydroperoxylinolenic acid to allene oxide can proceed in the absence of oxygen and NADPH. We have designed the synthesized of a series of novel imidazole derivatives and tested them in a bioassay as AOS inhibitors using a purified recombinant AOS enzyme isolated from Arabidopsis and expressed in E. coli. Among the derivatives prepared, heptyl 8-[1-(2,4-dichlorophenyl)-2-imidazolylethoxy]octanoate (k) was found to be the most potent inhibitor, with an IC(50) of 10+/-5 nM, which is 250,000-fold and 1,000,000-fold more potent than the known AOS inhibitors, acetylsalicyclic acid (2.5 mM) and ketoconazole (10 mM), respectively.