Carbazole and tetrahydro-carboline derivatives as dopamine D_(3) receptor antagonists with the multiple antipsychotic-like properties

Dopamine D_(3) receptor(D_(3)R)is implicated in multiple psychotic symptoms.Increasing the D_(3)R selectivity over dopamine D_2 receptor(D_2R)would facilitate the antipsychotic treatments.Herein,novel carbazole and tetrahydro-carboline derivatives were reported as D_(3)R selective ligands.Through a structure-based virtual screen,ZLG-25(D_(3)R K_i=685 nmol/L;D_2R K_i>10,000 nmol/L)was identified as a novel D_(3)R selective bitopic ligand with a carbazole scaffold.Scaffolds hopping led to the discovery of novel D_(3)R-selective analogs with tetrahydro-β-carboline or tetrahydro-γ-carboline core.Further functional studies showed that most derivatives acted as h D_(3)R-selective antagonists.Several lead compounds could dose-dependently inhibit the MK-801-induced hyperactivity.Additional investigation revealed that 23j and 36b could decrease the apomorphine-induced climbing without cataleptic reaction.Furthermore,36b demonstrated unusual antidepressant-like activity in the forced swimming tests and the tail suspension tests,and alleviated the MK-801-induced disruption of novel object recognition in mice.Additionally,preliminary studies confirmed the favorable PK/PD profiles,no weight gain and limited serum prolactin levels in mice.These results revealed that 36b provided potential opportunities to new antipsychotic drugs with the multiple antipsychotic-like properties.

Microscale thermophoresis in the investigation of biomolecular interactions

Accurate characterization of the interactions between biomolecules not only provides fundamental insights into cellular processes but also paves the way for drug discovery and development. With recent increases in throughput and sensitivity, biophysical technologies have become prominent tools for studying biomolecular interactions. Biophysical techniques that can reduce costs, shorten detection time, simplify the complexity of the system under analysis, and simultaneously provide high-quality data content are particularly favored. Here, we summarize the qualitative and quantitative analysis of biomolecular interactions using Micro Scale Thermophoresis(MST), as well as extend the application of MST functions to explore thermodynamics, enzyme kinetics and protein folding-unfolding processes. MST has emerged as a simple and powerful biophysical approach for identifying and quantifying binding events based on the movement of molecules along microscopic temperature gradients. The advantages of MST over other competitive biophysical techniques include freedom from immobilization, rapid analysis times, lower sample consumption, and the ability to analyze binding affinities in cell lysates. This article discusses the instrumental setups, principles, experimental workflows, and examples of MST application in practice.

Discovery of 4-arylthiophene-3-carboxylic acid as inhibitor of ANO1 and its effect as analgesic agent

Anoctamin 1(ANO1)is a kind of calcium-activated chloride channel involved in nerve depolarization.ANO1 inhibitors display significant analgesic activity by the local peripheral and intrathecal administration.In this study,several thiophenecarboxylic acid and benzoic acid derivatives were identified as novel ANO1 inhibitors through the shape-based virtual screening,among which the 4-arylthiophene-3-carboxylic acid analogues with the best ANO1 inhibitory activity were designed,synthesized and compound 42(IC;=0.79μmol/L)was finally obtained.Compound 42 selectively inhibited ANO1 without affecting ANO2 and intracellular Ca;concentration.Subsequently,the analgesic effect was investigated by intragastric administration in pain models.Compound 42 significantly attenuated allodynia which was induced by formalin and chronic constriction injury.Through homology modeling and molecular dynamics,the binding site was predicted to be located near the calcium-binding region betweenα6 andα8.Our study validates ANO1 inhibitors having a significant analgesic effect by intragastric administration and also provides selective molecular tools for ANO1-related research.