Alcives Avila-Sorrosa

Targeting quorum sensing by designing azoline derivatives to inhibit the N-hexanoyl homoserine lactone-receptor CviR: Synthesis as well as biological and theoretical evaluations

To counteract bacterial resistance, we investigated the interruption of quorum sensing mediated by non-classical bioisosteres of the N-hexanoyl homoserine lactone with an azoline core. For this purpose, a set of selected 2-substituted azolines was synthesized, establishing the basis for a new protocol to synthesize 2-amino imidazolines. The synthesized compounds were evaluated as inhibitors of violacein production in Chromobacterium violaceum. Theoretical studies on bioisostere-protein interactions were performed using CviR. The results show that some azolines decreased violacein production, suggesting an antiquorum sensing profile against Gram-negative bacteria. Docking and molecular dynamic simulations together with binding free energy calculations revealed the exact binding and inhibitory profiles. These theoretical results show relationship with the in vitro activity of the azoline series.

trans-Chlorido­(4-fluoro­benzene­thiol­ato-κS)bis­(tri­phenyl­phosphane-κP)palladium(II) methanol hemisolvate

The title compound, [Pd(SC6H4F-p)Cl(PPh3)2]·0.5CH3OH, features a PdII complex with two triphenylphosphane (PPh3) ligands arranged in a trans conformation, with one chloride and one 4-fluorobenzenethiolate ligand completing the coordination sphere, giving rise to a slightly distorted square-planar geometry of the PdII ion. The methanol solvent molecule is disordered about an inversion centre with an occupancy of 0.25 for each molecule. In the crystal, weak C—H⋯Cl hydrogen-bonding interactions between the complex molecules generate chain frameworks parallel to [010].

trans-Bis(μ-benzene­thiol­ato-κ2S:S)bis[chlorido­(tri­phenyl­phosphane-κP)palladium(II)] chloro­form disolvate

The title compound, [Pd2Cl2(C6H5S)2(C18H15P)2]·2CHCl3, contains a centrosymmetric dinuclear palladium complex with the PdII cation in a slightly distorted square-planar coordination environment. The PdII cations are bridged by the S atoms of two benzenethiolate ligands with different Pd—S distances [2.2970 (11) and 2.3676 (11) Å]. The coordination of the metal atom is completed by a chloride anion [2.3383 (11) Å] and a triphenylphosphane ligand [2.2787 (11) Å]. Weak C—H⋯Cl interactions are present between complex molecules and the CHCl3 solvent molecule. The latter is disordered over two positions in a 0.792 (8):0.208 (8) ratio. The crystal under investigation was found to be twinned by nonmerohedry, with a fraction of 73.4 (1)% for the major twin component.

1-Ethenyl-4-[(phenylsulfanyl)methyl]­benzene

The dihedral angle between the aromatic rings in the title compound, C15H14S, is 72.38 (7)°. In the crystal, the molecules are connected by C—H⋯π interactions.

3-[1-(3-Hy-droxy-benz-yl)-1H-benzimid-azol-2-yl]phenol dimethyl sulfoxide monosolvate.

Crystals of the title compound were obtained as a 1:1 dimethyl sulfoxide solvate, C20H16N2O2·C2H6O. The molecular conformation of the organic molecule is similar to that in the previously reported unsolvated structure [Eltayeb et al. (2009 ▶). Acta Cryst. E65, o1374–o1375]. Thus, the dihedral angles formed by the benzimidazole moiety with the two benzene rings are 57.54 (4) and 76.22 (5)°, and the dihedral angle between the benzene rings is 89.23 (5)°. In the crystal, a three-dimensional network features O—H⋯O, O—H⋯N and O—H⋯S hydrogen bonds, as well as C—H⋯O and C—H⋯π interactions.

[2-(Diphenyl­phosphan­yl)benzene­thiol­ato-κ2 P,S](pyridine-2-thiol­ato-κS)(triphenyl­phosphine-κP)palladium(II)

In the title compound, [Pd(C5H4NS)(C18H14PS)(C18H15P)], the PdII atom has a slightly distorted square-planar environment. Two coordination sites are occupied by a P,S-chelating 2-(diphenylphosphanyl)benzenethiolate ligand and the other two by a P atom from a triphenylphosphine ligand and an S atom from a pyridine-2-thiolate ligand, exhibiting a trans arrangement of the two P-donor atoms. In the crystal structure, weak intra- and intermolecular C—H⋯π and π–π interactions are observed. The pyridyl ring is equally disordered over two positions.