Discovery of a Highly Potent Oxysterol Receptor GPR183 Antagonist Bearing the Benzo[d]thiazole Structural Motif for the Treatment of Inflammatory Bowel Disease (IBD).

Accumulating evidence has demonstrated a critical pathological role of oxysterol receptor GPR183 in various inflammatory and autoimmune diseases, including inflammatory bowel disease (IBD). However, the currently reported GPR183 antagonists are very limited and not qualified for in vivo studies due to their inferior druglike properties. Herein, we conducted a structural elaboration focusing on improving its PK and safety profile based on a reference antagonist NIBR189. Of note, compound 33, bearing an aminobenzothiazole motif, exhibited reduced hERG inhibition, improved PK properties, and robust antagonistic activity (IC50 = 0.82 nM) with high selectivity against GPR183. Moreover, compound 33 displayed strong in vitro antimigration and anti-inflammatory activity in monocytes. Oral administration of compound 33 effectively improved the pathological symptoms of DSS-induced experimental colitis. All of these findings demonstrate that compound 33 is a novel and promising GPR183 antagonist suitable for further investigation to treat IBD.

Ruthenium-Catalyzed Ligand-Enabled Regiodivergent Difluoroallylation of Aryl C-H Bonds.

The gem-difluoroallyl group is a sought-after structural motif commonly found in pharmaceutical compounds. Despite its appeal, achieving a controlled synthesis of both α,α- and γ,γ-difluoroallylated compounds has proven to be a challenging task. This study presents a new approach to difluoroallylation, which utilizes a regiodivergent C-H bond reaction catalyzed by ruthenium catalysis. This method enables the meta and ortho C-H α,α- and ortho C-H γ,γ-difluoroallylation of arenes using 3-bromo-3,3-difluoropropenes.

Small molecules targeting cGAS-STING pathway for autoimmune disease.

Autoimmune diseases represent a class of over 80 illnesses with high incidence and prevalence and share a common pathogenesis of immune system disorders and self-attack. Over the past decade, extensive studies have demonstrated that imbalance of cGAS-STING mediated innate immune signaling is closely involved in autoimmune diseases. Over-activation of cGAS-STING pathway by mutations of STING or several exonucleases can cause accumulation of interferon and systemic inflammation. Therefore, suppression of the upregulated cGAS-STING pathway holds great potential in the treatment of human inflammatory and autoimmune diseases. Inhibitors targeting cGAS, STING and the downstream factors have been developed and pharmacologically evaluated recently. Herein, we summarize the recent advance on development of small molecular inhibitors targeting the key effectors in cGAS-STING axis as promising treatment for autoimmune diseases.

Piezo-Type Mechanosensitive Ion Channel Component 1 (Piezo1): A Promising Therapeutic Target and Its Modulators.

Piezo1 is a member of the mechanosensitive piezo ion channel family, which transduces various mechanical stimulations into electrochemical signals. Piezo1 is closely implicated in different physiological processes ranging from erythrocyte volume homeostasis to lymphatic vessel formation and bone homeostasis. Aberrant Piezo1 functions caused by gain-of-function or loss-of-function mutations are associated with various pathological conditions. Due to the significant contribution on the recognition of Piezo ion channels for sensing mechanical stress, Ardem Patapoutian received the 2021 Nobel Prize in Physiology or Medicine (jointly). Strategies of targeting and modulating Piezo1 have shown potential to produce significant therapeutic effects, thus validating Piezo1 as a promising drug target for diseases. In this Perspective, we review the cryo-EM structure, mechanogating mechanism, and physiological profiles of Piezo1, together with the latest advances in the development of its modulators. Limitations and challenges as well as future development of Piezo1 modulators are discussed as well.

Palladium-Catalyzed gem-Difluoroallylation Reaction between Aryltributyltin and Bromodifluoromethylated Alkenes.

A robust Stille gem-difluoroallylation of arylstannanes with 3-bromo-3,3-difluoropropenes has been established. The catalyst was found to exert critical effect on the reaction chemoselectivity. By using Pd(OH)2/C as the catalyst, a series of 3-(hetero)aryl/vinyl-3,3-difluoropropenes were obtained in high efficiency with α-substitution regioselectivity. The reaction has a broad substrate scope, and various substitution patterns were well tolerated in both substrates. Notably, the reaction can be easily extended to late-stage gem-difluoroallylation of many bioactive molecules with good chemoselectivity.