ABSTRACT
In seeking novel and potent small molecule hematopoietic prostaglandin D2 synthase (H-PGDS) inhibitors as potential therapies for PGD2-mediated diseases and conditions, we explored a series comprising multiple aryl/heteroaryl rings attached in a linear arrangement. Each compound incorporates an amide or imidazole "linker" between the pyrimidine or pyridine "core" ring and the "tail" ring system. We synthesized and screened twenty analogs by fluorescence polarization binding assay, thermal shift assay, glutathione S-transferase inhibition assay, and a cell-based assay measuring suppression of LPS-induced PGD2 stimulation. Amide analogs show ten-fold greater shift in the thermal shift assay in the presence of glutathione (GSH) versus the same assay run in the absence of GSH. The imidazole analogs did not produce a significant change in thermal shift between the two assay conditions, suggesting a possible stabilization effect of the amide linker in the synthase-GSH-inhibitor complex. Imidazole analog 23, (KMN-010034) demonstrates superior potency across the in vitro assays and good in vitro metabolic stability in both human and guinea pig liver microsomes.
Subject(s)
Amides/pharmacology , Enzyme Inhibitors/pharmacology , Imidazoles/pharmacology , Intramolecular Oxidoreductases/antagonists & inhibitors , Lipocalins/antagonists & inhibitors , Amides/chemical synthesis , Amides/chemistry , Animals , Dose-Response Relationship, Drug , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Guinea Pigs , Humans , Imidazoles/chemical synthesis , Imidazoles/chemistry , Intramolecular Oxidoreductases/metabolism , Lipocalins/metabolism , Lipopolysaccharides/antagonists & inhibitors , Lipopolysaccharides/pharmacology , Microsomes, Liver/chemistry , Microsomes, Liver/metabolism , Molecular Structure , Structure-Activity RelationshipABSTRACT
A series of small-molecule full agonists of the prostaglandin E2 type 4 (EP4) receptor have been generated and evaluated for binding affinity and cellular potency. KMN-80 and its gem-difluoro analog KMN-159 possess high selectivity relative to other prostanoid receptors. Difluoro substitution is positioned alpha to the lactam ring carbonyl and results in KMN-159's fivefold increase in potency versus KMN-80. The two analogs exhibit electronic and conformational variations, including altered nitrogen hybridization and lactam ring puckering, that may drive the observed difluoro-associated increased potency within this four-compound series.
Subject(s)
Alprostadil/analogs & derivatives , Alprostadil/pharmacology , Heptanoic Acids/pharmacology , Lactams/pharmacology , Pyrrolidines/pharmacology , Receptors, Prostaglandin E, EP4 Subtype/agonists , Alprostadil/metabolism , Animals , Binding Sites , CHO Cells , Caco-2 Cells , Cricetulus , Humans , Lactams/chemical synthesis , Lactams/metabolism , Models, Chemical , Molecular Docking Simulation , Molecular Structure , Quantum Theory , Receptors, Prostaglandin E, EP3 Subtype/chemistry , Receptors, Prostaglandin E, EP3 Subtype/metabolism , Receptors, Prostaglandin E, EP4 Subtype/chemistry , Receptors, Prostaglandin E, EP4 Subtype/metabolismABSTRACT
A series of 2-(1H-pyrazol-1-yl)pyridines are described as inhibitors of ALK5 (TGFß receptor I kinase). Modeling compounds in the ALK5 kinase domain enabled some optimization of potency via substitutions on the pyrazole core. One of these compounds PF-03671148 gave a dose dependent reduction in TGFß induced fibrotic gene expression in human fibroblasts. A similar reduction in fibrotic gene expression was observed when PF-03671148 was applied topically in a rat wound repair model. Thus these compounds have potential utility for the prevention of dermal scarring.
Subject(s)
Cicatrix/prevention & control , Drug Discovery , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Pyridines/chemistry , Pyridines/pharmacology , Receptors, Transforming Growth Factor beta/antagonists & inhibitors , Skin/drug effects , Animals , Models, Molecular , Phosphorylation , Rats , Receptor, Transforming Growth Factor-beta Type IABSTRACT
"K2/SPICE" products are commonly laced with aminoalkylindole synthetic cannabinoids (i.e., JWH-018 and JWH-073) and are touted as "legal" marijuana substitutes. Here we validate a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for measuring urinary concentrations of JWH-018, JWH-073, and several potential metabolites of each. The analytical procedure has high capacity for sample throughput and does not require solid phase or liquid extraction. Evaluation of human urine specimens collected after the subjects reportedly administered JWH-018 or a mixture of JWH-018 and JWH-073 provides preliminary evidence of clinical utility. Two subjects that consumed JWH-018 primarily excreted glucuronidated conjugates of 5-(3-(1-naphthoyl)-1H-indol-1-yl)-pentanoic acid (>30 ng/mL) and (1-(5-hydroxypentyl)-1H-indol-3-yl)(naphthalene-1-yl)-methanone (>50 ng/mL). Interestingly, oxidized metabolites of both JWH-018 and JWH-073 were detected in these specimens, suggesting either metabolic demethylation of JWH-018 to JWH-073 or a nonreported, previous JWH-073 exposure. Metabolic profiles generated from a subject who consumed a mixture of JWH-018 and JWH-073 were similar to profiles generated from subjects who presumably consumed JWH-018 exclusively. Oxidized metabolites of JWH-018 and JWH-073 were of the same pattern, but JWH-018 metabolites were excreted at lower concentrations. These results begin clinically validating the LC-MS/MS assay for detecting and quantifying aminoalkylindole metabolites. Full validation awaits further testing.
