ABSTRACT
The transcription factor RORγt is an attractive drug-target due to its role in the differentiation of IL-17 producing Th17 cells that play a critical role in the etiopathology of several autoimmune diseases. Identification of starting points for RORγt inverse agonists with good properties has been a challenge. We report the identification of a fragment hit and its conversion into a potent inverse agonist through fragment optimization, growing and merging efforts. Further analysis of the binding mode revealed that inverse agonism was achieved by an unusual mechanism. In contrast to other reported inverse agonists, there is no direct interaction or displacement of helix 12 observed in the crystal structure. Nevertheless, compound 9 proved to be efficacious in a delayed-type hypersensitivity (DTH) inflammation model in rats.
Subject(s)
Drug Discovery , Drug Inverse Agonism , Nuclear Receptor Subfamily 1, Group F, Member 3/agonists , Animals , Catalytic Domain , Disease Models, Animal , Female , Inflammation/metabolism , Models, Molecular , RatsABSTRACT
A series of potent quinazolinedione sulfonamide antagonists of the α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) receptor were designed and synthesized. The structure-activity relationships (SAR) and inâ vivo activity of the series were investigated. In particular, compound 1 S (selurampanel; N-[7-isopropyl-6-(2-methylpyrazol-3-yl)-2,4-dioxo-1H-quinazolin-3-yl]methanesulfonamide) has shown excellent oral potency against maximal electroshock seizure (MES)-induced generalized tonic-clonic seizures in rodents as well as significant activity in patients suffering from various forms of epilepsy. The X-ray crystal structure of selurampanel bound to the AMPA receptor hGluA was also obtained.
Subject(s)
Drug Design , Quinazolinones/chemistry , Receptors, AMPA/antagonists & inhibitors , Administration, Oral , Animals , Binding Sites , Binding, Competitive , Crystallography, X-Ray , Disease Models, Animal , Electroshock , Mice , Molecular Dynamics Simulation , Protein Structure, Tertiary , Quinazolinones/administration & dosage , Quinazolinones/chemical synthesis , Quinazolinones/metabolism , Receptors, AMPA/metabolism , Seizures/drug therapy , Structure-Activity Relationship , Sulfonamides/administration & dosage , Sulfonamides/chemical synthesis , Sulfonamides/chemistry , Sulfonamides/metabolismABSTRACT
Retinoic-acid-related orphan receptorâ γt (RORγt) is a key transcription factor implicated in the production of pro-inflammatory Th17 cytokines, which drive a number of autoimmune diseases. Despite diverse chemical series having been reported, combining high potency with a good physicochemical profile has been a very challenging task in the RORγt inhibitor field. Based on available chemical structures and incorporating in-house knowledge, a new series of triazolo- and imidazopyridine RORγt inverse agonists was designed. In addition, replacement of the terminal cyclopentylamide metabolic soft spot by five-membered heterocycles was investigated. From our efforts, we identified an optimal 6,7,8-substituted imidazo[1,2-a]pyridine core system and a 5-tert-butyl-1,2,4-oxadiazole as cyclopentylamide replacement leading to compounds 10 ((S)-N-(8-((4-(cyclopentanecarbonyl)-3-methylpiperazin-1-yl)methyl)-7-methylimidazo[1,2-a]pyridin-6-yl)-2-methylpyrimidine-5-carboxamide) and 33 ((S)-N-(8-((4-(5-(tert-butyl)-1,2,4-oxadiazol-3-yl)-3-methylpiperazin-1-yl)methyl)-7-methylimidazo[1,2-a]pyridin-6-yl)-2-methylpyrimidine-5-carboxamide). Both derivatives showed good pharmacological potencies in biochemical and cell-based assays combined with excellent physicochemical properties, including low to medium plasma protein binding across species. Finally, 10 and 33 were shown to be active in a rodent pharmacokinetic/pharmacodynamic (PK/PD) model after oral gavage at 15â mg kg-1 , lowering IL-17 cytokine production in exâ vivo antigen recall assays.
Subject(s)
Drug Inverse Agonism , Imidazoles , Nuclear Receptor Subfamily 1, Group F, Member 3/agonists , Pyridines/chemical synthesis , Receptors, Retinoic Acid/agonists , Triazoles , Animals , Binding Sites , Cells, Cultured , Crystallography, X-Ray , Humans , Imidazoles/chemical synthesis , Imidazoles/chemistry , Imidazoles/pharmacology , Inhibitory Concentration 50 , Interleukin-17/blood , Molecular Structure , Protein Binding/drug effects , Pyridines/chemistry , Pyridines/pharmacology , Rats , Triazoles/chemical synthesis , Triazoles/chemistry , Triazoles/pharmacologyABSTRACT
Surface sampling micro liquid chromatography tandem mass spectrometry (SSµLC-MS/MS) was explored as a quantitative tissue distribution technique for probing compound properties in drug discovery. A method was developed for creating standard curves using surrogate tissue sections from blank tissue homogenate spiked with compounds. The resulting standard curves showed good linearity and high sensitivity. The accuracy and precision of standards met acceptance criteria of ±30%. A new approach was proposed based on an experimental and mathematical method for tissue extraction efficiency evaluation by means of consecutively sampling a location on tissue twice by SSµLC-MS/MS. The observed extraction efficiency ranged from 69% to 82% with acceptable variation for the test compounds. Good agreement in extraction efficiency was observed between surrogate tissue sections and incurred tissue sections. This method was successfully applied to two case studies in which tissue distribution was instrumental in advancing project teams' understanding of compound properties.
Subject(s)
Drug Discovery , Pharmaceutical Preparations/analysis , Chromatography, Liquid/instrumentation , Surface Properties , Tandem Mass Spectrometry/instrumentationABSTRACT
The disposition and biotransformation of (14)C-radiolabeled mavoglurant were investigated in four healthy male subjects after a single oral dose of 200 mg. Blood, plasma, urine, and feces collected over 7 days were analyzed for total radioactivity, mavoglurant was quantified in plasma by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), and metabolite profiles were generated in plasma and excreta by high-performance liquid chromatography (HPLC) and radioactivity detection. The chemical structures of mavoglurant metabolites were characterized by LC-MS/MS, wet-chemical and enzymatic methods, NMR spectroscopy, and comparison with reference compounds. Mavoglurant was safe and well tolerated in this study population. Mavoglurant absorption was ≥50% of dose reaching mean plasma Cmax values of 140 ng/ml (mavoglurant) and 855 ng-eq/ml (total radioactivity) at 2.5 and 3.6 hours, respectively. Thereafter, mavoglurant and total radioactivity concentrations declined with mean apparent half-lives of 12 and 18 hours, respectively. The elimination of mavoglurant occurred predominantly by oxidative metabolism involving primarily 1) oxidation of the tolyl-methyl group to a benzyl-alcohol metabolite (M7) and subsequently to a benzoic acid metabolite (M6), and 2) oxidation of the phenyl-ring leading to a hydroxylated metabolite (M3). The subjects were mainly exposed to mavoglurant and seven main metabolites, which combined accounted for 60% of (14)C-AUC0-72 h (area under the concentration-time curve from time 0 to infinity). The primary steps of mavoglurant metabolism observed in vivo could partially be reproduced in vitro in incubations with human liver microsomes and recombinant cytochrome P450 enzymes. After 7 days, the mean balance of total radioactivity excretion was almost complete (95.3% of dose) with 36.7% recovered in urine and 58.6% in feces.
Subject(s)
Indoles/metabolism , Indoles/pharmacokinetics , Receptor, Metabotropic Glutamate 5/antagonists & inhibitors , Receptor, Metabotropic Glutamate 5/metabolism , Absorption , Adult , Area Under Curve , Carbon Radioisotopes/blood , Carbon Radioisotopes/metabolism , Carbon Radioisotopes/pharmacokinetics , Carbon Radioisotopes/urine , Cytochrome P-450 Enzyme System/metabolism , Feces/chemistry , Half-Life , Humans , Indoles/blood , Indoles/urine , Male , Microsomes, Liver/enzymology , Microsomes, Liver/metabolism , Oxidation-ReductionABSTRACT
1H-pyrrolo[2,3-c]pyridine-7-carboxamides constitute a new series of allosteric mGluR5 antagonists. Variation of the substituents attached to the heterocyclic scaffold allowed to improve the physico-chemical parameters for optimization of the aqueous solubility while retaining high in vitro potency.
Subject(s)
Amides/chemistry , Amides/pharmacology , Pyridones/chemistry , Pyridones/pharmacology , Receptors, Metabotropic Glutamate/antagonists & inhibitors , Allosteric Regulation/drug effects , Drug Discovery , Humans , Inhibitory Concentration 50 , Pyrroles/chemistry , Pyrroles/pharmacology , Receptor, Metabotropic Glutamate 5 , Receptors, Metabotropic Glutamate/metabolism , SolubilityABSTRACT
A new set of quinazolinedione sulfonamide derivatives as competitive AMPA receptor antagonist with improved properties compared to 1 is disclosed. By modulating physico-chemical properties, compound 29 was identified with a low ED(50) of 5.5mg/kg in an animal model of anticonvulsant activity after oral dosage.
Subject(s)
Anticonvulsants/pharmacology , Quinazolinones/pharmacology , Receptors, AMPA/antagonists & inhibitors , Sulfonamides/pharmacology , Administration, Oral , Animals , Anticonvulsants/administration & dosage , Anticonvulsants/chemistry , Crystallography, X-Ray , Disease Models, Animal , Dose-Response Relationship, Drug , Mice , Mice, Inbred DBA , Models, Molecular , Molecular Structure , Quinazolinones/administration & dosage , Quinazolinones/chemistry , Seizures/drug therapy , Stereoisomerism , Structure-Activity Relationship , Sulfonamides/administration & dosage , Sulfonamides/chemistryABSTRACT
Quinazoline-2,4-diones with a sulfonamide group attached to the N(3) ring atom constitute a novel class of competitive AMPA receptor antagonists. One of the synthesized compounds, 28, shows nanomolar receptor affinity, whereas other examples of the series display oral anticonvulsant activity in animal models.
Subject(s)
Quinazolinones/chemical synthesis , Receptors, AMPA/antagonists & inhibitors , Sulfonamides/chemical synthesis , Administration, Oral , Animals , Anticonvulsants/pharmacology , Binding, Competitive/drug effects , Crystallography, X-Ray , Mice , Molecular Structure , Quinazolinones/chemistry , Quinazolinones/pharmacology , Rats , Structure-Activity Relationship , Sulfonamides/chemistry , Sulfonamides/pharmacologyABSTRACT
A focused chemical optimization effort of compound 1 based on metabolite elucidation is described, resulting in 15i, a highly potent and selective mGlu5 receptor antagonist with an improved pharmacokinetic profile compared to 1. Characterization of 15i in vivo in the fear-potentiated startle (FPS) paradigm revealed a robust reduction of conditioned fear behavior. This effect nicely correlates with the rat brain pharmacokinetics.
Subject(s)
Receptors, AMPA/antagonists & inhibitors , Analgesics/chemistry , Analgesics/pharmacology , Analgesics/therapeutic use , Animals , Anticonvulsants/chemistry , Anticonvulsants/pharmacology , Anticonvulsants/therapeutic use , Antipsychotic Agents/chemistry , Antipsychotic Agents/pharmacology , Antipsychotic Agents/therapeutic use , Clinical Trials as Topic , Drug Evaluation, Preclinical , Humans , Neuroprotective Agents/chemistry , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Protein Subunits/antagonists & inhibitors , Protein Subunits/genetics , Protein Subunits/physiology , Receptors, AMPA/genetics , Receptors, AMPA/physiologyABSTRACT
The total synthesis of jiadifenin has been accomplished. The synthesis allows us to build an SAR profile which suggests that the jiadifenin skeleton may be less desirable from the standpoint of nominating a potential drug than that of its prerearrangement precursor. The key steps of the jiadifenin problem involve the construction of two 1,3-related quaternary carbons. The paper describes how the stereochemistry was managed in this context. The issue was studied in considerable detail at the level of a then new allyl transfer reaction arising from a palladium-mediated transfer process of an allyl carbonate. By use of externally deuterated diallyl carbonate, we could probe, for the first time, the stereochemical relationship between the inter- and intramolecular versions of this process. The existence of concurrent inter- and intramolecular allylation reactions was demonstrated by deuteration experiments. While in the particular case at hand, we find very little difference in stereochemical outcome as one partitions between the inter- and intramolecular pathways, the techniques employed are applicable to other systems.
Subject(s)
Allyl Compounds/chemistry , Sesquiterpenes/chemical synthesis , Palladium/chemistry , Sesquiterpenes/pharmacology , Stereoisomerism , Structure-Activity RelationshipABSTRACT
[structure, reaction: see text] A full account of the total synthesis of neurotrophic compound NGA0187 is provided. A key feature of the synthesis involved the direct selective oxidation of 6alpha,7beta-diol to install the unusual 6,7-ketol moiety and stereoselective conjugate addition of vinyl cuprate to enone. A preliminary evaluation of its ability to stimulate the neurite outgrowth was also evaluated with PC12 cell.
Subject(s)
Neurons/drug effects , Triterpenes/chemical synthesis , Triterpenes/pharmacology , Animals , Cell Proliferation/drug effects , Crystallography, X-Ray , Drug Evaluation, Preclinical , Models, Molecular , Molecular Conformation , Nerve Growth Factor/pharmacology , PC12 Cells , Rats , Stereoisomerism , Structure-Activity Relationship , Triterpenes/chemistryABSTRACT
We report the first total synthesis of jiadifenin (1), the establishment of a modality for its biological evaluation, and the discovery of apparently more potent neurotrophic activity in fully synthetic compound 17, an intermediate en route to 1.