Synthesis, Docking Study and Biological Evaluation of Amide-Based Soluble Epoxide Hydrolase Inhibitors with Novel Secondary Pharmacophore of Pyrimidin-2-ol.

Soluble epoxide hydrolase enzyme (sEH) is one of the most promising and emerging targets to develop drugs for multiple disease indications, including hypertension, diabetes, stroke, dyslipidemia, pain, etc. Most inhibitor scaffolds have a urea or amide moiety to mimic the active-site transition state. In this regard, we developed a series of amide sEH inhibitors with a pyrimidin-2-ol ring as a new secondary pharmacophore, which was subjected to in vitro evaluation. Compound 4w (4-chloro-N-{4-[6-(4-chlorophenyl)-2-hydroxypyrimidin-4-yl]phenyl}benzamide), which contains 4-chloro substituent in both terminal phenyl rings, exhibited the most inhibitory activity against sEH with an IC50 value of 1.2 nM. Molecular docking analysis of the synthesized compounds revealed that the greater number of hydrogen bonding interactions of the amide group as the primary pharmacophore with Asp-353, Tyr-383, and Tyr-466 as the key catalytic residue triad of the enzyme played a critical role and led to a more favorable binding affinity. Pharmacokinetic properties of the synthesized compounds were calculated in silico, and all ADMET indices fell within acceptable ranges. Altogether, the results of this work could provide useful information on 4,6-diphenylpyrimidin-2-olas sEH inhibitors which can be utilized in further development in this area.

5-[Aryloxypyridyl (or nitrophenyl)]-4H-1,2,4-triazoles as novel flexible benzodiazepine analogues: Synthesis, receptor binding affinity and lipophilicity-dependent anti-seizure onset of action.

A new series of 5-(2-aryloxy-4-nitrophenyl)-4H-1,2,4-triazoles and 5-(2-aryloxy-3-pyridyl)-4H-1,2,4-triazoles, possessing C-3 thio or alkylthio substituents, was synthesized and evaluated for their benzodiazepine receptor affinity and anti-seizure activity. These analogues revealed similar to significantly superior affinity to GABAA/benzodiazepine receptor complex (IC50 values of 0.04-4.1 nM), relative to diazepam as the reference drug (IC50 value of 2.4 nM). To determine the onset of anti-seizure activity, the time-dependent effectiveness of i.p. administration of compounds on pentylenetetrazole induced seizure threshold was studied and a very good relationship was observed between the lipophilicity (cLogP) and onset of action of studied analogues (r2 = 0.964). The minimum effective dose of the compounds, determined at the time the analogues showed their highest activity, was demonstrated to be 0.025-0.1 mg/kg, relative to diazepam (0.025 mg/kg).