5-sulfonyl-benzimidazoles as selective CB2 agonists-part 2.

In a previous communication, the SAR of a series of potent and selective 5-sulfonyl-benzimidazole CB2-receptor agonists was described. The lack of in vivo activity of compounds from this series was attributed to their poor solubility and metabolic stability. In this Letter, we report on the further optimization of this series, leading to the relatively polar and peripherically acting CB2 agonists 41 and 49. Although both compounds were not active in acute pain models, the less selective compound 41 displayed good, sustained activity in a chronic model of neuropathic pain without the tolerance observed with morphine. In addition, both 41 and 49 delayed the onset of clinical symptoms in an experimental model for Multiple sclerosis.

Synthesis and structure-activity relationship of benzetimide derivatives as human CXCR3 antagonists.

The synthesis and evaluation of benzetimide derivatives showing potent CXCR3 antagonism are described. Optimization of the screening hits led to the identification of more potent CXCR3 antagonists devoid of anti-cholinergic activity and identification of the key pharmacophore moieties of the series.

Design and optimization of aniline-substituted tetrahydroquinoline C5a receptor antagonists.

A series of aniline-substituted tetrahydroquinoline C5a receptor antagonists were discovered. A functionality requirement of ortho substitution on the aniline was revealed. Secondary anilines, in general, outperformed tertiary analogs in inhibition of C5a-induced calcium mobilization. Further enhancement of activity was realized in the presence of an ortho hydroxyalkyl side chain. The functional IC(50) of selected analogs was optimized to the single-digit nanomolar level.