Synthesis and SAR studies of novel benzodiazepinedione-based inhibitors of Clostridium difficile (C. difficile) toxin B (TcdB).

Synthesis and structure-activity relationships (SAR) of a novel series of benzodiazepinedione-based inhibitors of Clostridium difficile toxin B (TcdB) are described. Compounds demonstrating low nanomolar affinity for TcdB, and which possess improved stability in mouse plasma vs. earlier compounds from this series, have been identified.

Treatment of Clostridium difficile Infection with a Small-Molecule Inhibitor of Toxin UDP-Glucose Hydrolysis Activity.

infection (CDI) is the leading cause of hospital-acquired infectious diarrhea, with significant morbidity, mortality, and associated health care costs. The major risk factor for CDI is antimicrobial therapy, which disrupts the normal gut microbiota and allows to flourish. Treatment of CDI with antimicrobials is generally effective in the short term, but recurrent infections are frequent and problematic, indicating that improved treatment options are necessary.

Identification and initial optimization of inhibitors of Clostridium difficile (C. difficile) toxin B (TcdB).

The discovery, synthesis and preliminary structure-activity relationship (SAR) of a novel class of inhibitors of Clostridium difficile (C. difficile) toxin B (TcdB) is described. A high throughput screening (HTS) campaign resulted in the identification of moderately active screening hits 1-5 the most potent of which was compound 1 (IC = 0.

Small molecule chemokine mimetics suggest a molecular basis for the observation that CXCL10 and CXCL11 are allosteric ligands of CXCR3.

Background And Purpose: The chemokine receptor CXCR3 directs migration of T-cells in response to the ligands CXCL9/Mig, CXCL10/IP-10 and CXCL11/I-TAC. Both ligands and receptors are implicated in the pathogenesis of inflammatory disorders, including atherosclerosis and rheumatoid arthritis. Here, we describe the molecular mechanism by which two synthetic small molecule agonists activate CXCR3.

Synthesis of (3,4-dimethoxyphenoxy)alkylamino acetamides as orexin-2 receptor antagonists.

The discovery and synthesis of a series of (dimethoxyphenoxy)alkylamino acetamides as orexin-2 receptor antagonists from a small-molecule combinatorial library using a high-throughput calcium mobilization functional assay (HEK293-human OX2-R cell line) is described. Active compounds show a good correlation between high-throughput single concentration screening data and measured IC(50)s. Specific examples exhibit IC(50) values of approximately 20 nM using human orexin A as the peptide agonist for the orexin-2 receptor.

Identification of CXCR3 receptor agonists in combinatorial small-molecule libraries.

In a high-throughput screen of four million compounds from combinatorial libraries for small-molecule modulators of the chemokine receptor CXCR3, two classes of receptor agonists, based on tetrahydroisoquinoline and piperidinyl diazepanone templates, were identified. Several of these compounds stimulated calcium flux in HEK293 cells expressing the recombinant human CXCR3 receptor with efficacies and kinetics similar to those of native ligand CXCL11/I-TAC and stimulated chemotaxis of activated human T-cells. The agonist small molecules also inhibited binding of another CXCR3 ligand, CXCL10/IP-10, to the receptor.

Identification and initial evaluation of 4-N-aryl-[1,4]diazepane ureas as potent CXCR3 antagonists.

The identification and evaluation of aryl-[1,4]diazepane ureas as functional antagonists of the chemokine receptor CXCR3 are described. Specific examples exhibit IC(50) values of approximately 60 nM in a calcium mobilization functional assay, and dose-dependently inhibit CXCR3 functional response to CXCL11 (interferon-inducible T-cell alpha chemoattractant/I-TAC) as measured by T-cell chemotaxis, with a potency of approximately 100 nM.