Shannon M. Biros

Structure and binding properties of water-soluble cavitands and capsules

Synthetic receptors are modern tools for investigations into the forces involved in recognition. A widely exploited class of receptors are the resorcin[4]arene-based cavitands and capsules. This critical review (71 references) describes the evolution of water-soluble versions of these structures, along with insights the resulting host-ndash complexes have provided with regard to complexation driving forces in water. An emphasis has been placed on the influence of host structure on guest affinity and dynamics.

A novel, systemically active, selective galanin receptor type-3 ligand exhibits antidepressant-like activity in preclinical tests

The neuropeptide galanin is widely expressed in limbic nuclei in the brain, and plays an important role in the regulation of homeostatic and affective behaviors, in part through its modulation of central monoamine pathways. Recent evidence suggests that galanin and its receptors may be involved in the efficacy of various modalities of antidepressant treatments. We have previously demonstrated that systemically active, non-peptide galanin receptor type-1/2 agonists exhibit antidepressant-like effects in the rat forced swim test. Here we evaluate a novel galanin receptor type-3 (GalR3) antagonist in preclinical tests of anxiety and depression. At multiple doses, the compound displayed no effects in the elevated plus maze in mice. By contrast, the compound decreased time spent immobile in the tail suspension test by mice. Additionally, the GalR3 drug decreased time spent immobile in the forced swim test in rats, similarly to the effects of desipramine, yet did not increase locomotor activity in an open field test. These combined data from two species indicate that GalR3 receptor antagonists may exhibit antidepressant-like effects.

Normal hydrocarbons tumble rapidly in a deep, water-soluble cavitand

A deep, water-soluble cavitand extracts n-alkanes and other water-insoluble species into its cavity via hydrophobic forces: alkanes bind in a helical manner, and tumble rapidly on the NMR timescale inside the binding pocket.

FACILE SYNTHESIS OF PYRIDAZINE-BASED α-HELIX MIMETICS

The synthesis of an amphiphilic, nonpeptidic scaffold that mimics the presentation of i, i+4, and i+7 residues of an α-helix is presented. The approach uses a pyridazine core, and minimizes the number of C-C bond forming reactions. The synthesis of this Urea-Pyridazine-Piperazine (UPP) scaffold is versatile and its synthesis makes it suitable for the preparation of small libraries of low-molecular-weight α-helix mimetics that can be targeted to specific protein/protein interactions.

Binding properties of cavitands in aqueous solution-the influence of charge on guest selectivity

The charge of the upper rim has influences on the binding properties of cavitands in aqueous media.

Crystal structure of 2,4-di-nitro-phenyl 4-methyl-benzene-sulfonate: a new polymorph.

The title compound, C13H10N2O7S, was solved in the orthorhombic space group Pna21. The aromatic substituents on the sulfonate group are oriented gauche to one another with a C—O—S—C torsion angle of −62.0 (3)°. The supramolecular features that contribute to the crystal lattice are offset π-π and multiple C—H⋯O interactions.

Crystal structure of 3,5-di­methyl­phenyl 2-nitro­benzene­sulfonate

In the title compound, there are intermolecular S=O⋯N(nitro) interactions, with an O⋯N distance of 2.9840 (18) Å, between inversion-related molecules. The aromatic rings attached to the SO3 group are oriented in a gauche fashion around the ester S—O bond, with a C—S—O—C torsion angle of 84.68 (11)°.

Crystal structure of N-[(1S,2S)-2-amino­cyclo­hex­yl]-2,4,6-tri­methyl­benzene­sulfonamide

In the crystal structure of the title compound, the sulfonamide N—H group forms an intermolecular hydrogen bond to the amine N atom.

Crystal structure of N -allyl-4-methylbenzenesulfonamide

In the crystal structure of the title sulfonamide, intermolecular N—H⋯O hydrogen bonds are present between sulfonamide groups, as well as offset π–π interactions.

Crystal structure of cis-[1,2-bis-(di-phenyl-phosphan-yl)ethene-κ2P,P']di-chlorido-platinum(II) chloro-form disolvate: a new polymorph.

A third monoclinic polymorph of the title compound is described. In the crystal, it exhibits C—H⋯Cl hydrogen bonds and face-on Cl⋯π interactions involving the chloroform disolvate molecules. Intermolecular weak offset π–π interactions are also present between the aromatic rings of the ligands.