ABSTRACT
Transient-receptor-potential melastatin 8 (TRPM8), the predominant mammalian cold-temperature thermosensor, is a nonselective cation channel expressed in a subpopulation of sensory neurons in the peripheral nervous system, including nerve circuitry implicated in migraine pathogenesis: the trigeminal and pterygopalatine ganglia. Genomewide association studies have identified an association between TRPM8 and reduced risk of migraine. This disclosure focuses on medicinal-chemistry efforts to improve the druglike properties of initial leads, particularly removal of CYP3A4-induction liability and improvement of pharmacokinetic properties. A novel series of biarylmethanamide TRPM8 antagonists was developed, and a subset of leads were evaluated in preclinical toxicology studies to identify a clinical candidate with an acceptable preclinical safety profile leading to clinical candidate AMG 333, a potent and highly selective antagonist of TRPM8 that was evaluated in human clinical trials.
Subject(s)
Anticonvulsants/pharmacology , Drug Discovery , Migraine Disorders/prevention & control , Niacin/chemistry , Seizures/drug therapy , TRPM Cation Channels/antagonists & inhibitors , Animals , Anticonvulsants/chemistry , Calcium Channel Agonists/toxicity , Humans , Male , Microsomes, Liver/drug effects , Models, Molecular , Molecular Structure , Pyrimidinones/toxicity , Rats , Rats, Sprague-Dawley , Seizures/chemically inducedABSTRACT
Orally bioavailable SERDs may offer greater systemic drug exposure, improved clinical efficacy, and more durable treatment outcome for patients with ER-positive endocrine-resistant breast cancer. We report the design and synthesis of a boronic acid modified fulvestrant (5, ZB716), which binds to ERα competitively (IC50 = 4.1 nM) and effectively downregulates ERα in both tamoxifen-sensitive and tamoxifen-resistant breast cancer cells. Furthermore, It has superior oral bioavailability (AUC = 2547.1 ng·h/mL) in mice, indicating its promising clinical utility as an oral SERD.
Subject(s)
Boronic Acids/chemistry , Selective Estrogen Receptor Modulators/chemistry , Sterols/chemistry , Administration, Oral , Animals , Biological Availability , Boronic Acids/chemical synthesis , Boronic Acids/pharmacology , Breast Neoplasms , Cell Line, Tumor , Cell Proliferation/drug effects , Down-Regulation , Drug Resistance, Neoplasm , Estrogen Receptor alpha/metabolism , Female , Mice, Inbred C57BL , Selective Estrogen Receptor Modulators/chemical synthesis , Selective Estrogen Receptor Modulators/pharmacology , Signal Transduction , Stereoisomerism , Sterols/chemical synthesis , Sterols/pharmacology , Tamoxifen/pharmacologyABSTRACT
The ß-site amyloid precursor protein (APP) cleaving enzyme 1 (BACE1) is one of the most hotly pursued targets for the treatment of Alzheimer's disease. We used a structure- and property-based drug design approach to identify 2-aminooxazoline 3-azaxanthenes as potent BACE1 inhibitors which significantly reduced CSF and brain Aß levels in a rat pharmacodynamic model. Compared to the initial lead 2, compound 28 exhibited reduced potential for QTc prolongation in a non-human primate cardiovascular safety model.
Subject(s)
Amyloid Precursor Protein Secretases/antagonists & inhibitors , Aspartic Acid Endopeptidases/antagonists & inhibitors , Protease Inhibitors/chemistry , Protease Inhibitors/pharmacology , Xanthenes/chemistry , Xanthenes/pharmacology , Alzheimer Disease/drug therapy , Animals , Cell Line , HEK293 Cells , Humans , Protease Inhibitors/chemical synthesis , Rats , Xanthenes/chemical synthesisABSTRACT
γ-Secretase modulators (GSMs) are potentially disease-modifying treatments for Alzheimer's disease. They selectively lower pathogenic Aß42 levels by shifting the enzyme cleavage sites without inhibiting γ-secretase activity, possibly avoiding known adverse effects observed with complete inhibition of the enzyme complex. A cell-based HTS effort identified the sulfonamide 1 as a GSM lead. Lead optimization studies identified compound 25 with improved cell potency, PKDM properties, and it lowered Aß42 levels in the cerebrospinal fluid (CSF) of Sprague-Dawley rats following oral administration. Further optimization of 25 to improve cellular potency is described.
Subject(s)
Alzheimer Disease/drug therapy , Amides/pharmacology , Amyloid Precursor Protein Secretases/metabolism , Picolines/pharmacology , Alzheimer Disease/enzymology , Amides/chemistry , Animals , HEK293 Cells , Humans , Picolines/chemistry , Rats , Rats, Sprague-DawleyABSTRACT
All eight of the major active metabolites of (S)-2-((1S,2S,4R)-bicyclo[2.2.1]heptan-2-ylamino)-5-isopropyl-5-methylthiazol-4(5H)-one (AMG 221, compound 1), an inhibitor of 11ß-hydroxysteroid dehydrogenase type 1 that has entered the clinic for the treatment of type 2 diabetes, were synthetically prepared and confirmed by comparison with samples generated in liver microsomes. After further profiling, we determined that metabolite 2 was equipotent to 1 on human 11ß-HSD1 and had lower in vivo clearance and higher bioavailability in rat and mouse. Compound 2 was advanced into a pharmacodynamic model in mouse where it inhibited adipose 11ß-HSD1 activity.
ABSTRACT
The bradykinin B1 receptor has been shown to mediate pain response and is rapidly induced upon injury. Blocking this receptor may provide a promising treatment for inflammation and pain. We previously reported tetralin benzyl amines as potent B1 antagonists. Here we describe the synthesis and SAR of B1 receptor antagonists with homobenzylic amines. The SAR of different linkers led to the discovery of tetralin allylic amines as potent and selective B1 receptor antagonists (hB1 IC(50)=1.3 nM for compound 16). Some of these compounds showed modest oral bioavailability in rats.
Subject(s)
Benzylamines/chemistry , Bradykinin B1 Receptor Antagonists , Sulfonamides/chemistry , Tetrahydronaphthalenes/chemistry , Administration, Oral , Animals , Pain/drug therapy , Rats , Receptor, Bradykinin B1/metabolism , Structure-Activity Relationship , Sulfonamides/pharmacokinetics , Sulfonamides/therapeutic useABSTRACT
Through a combination of screening and structure-based rational design, we have discovered a series of N(1)-(5-(heterocyclyl)-thiazol-2-yl)-3-(4-trifluoromethylphenyl)-1,2-propanediamines that were developed into potent ATP competitive inhibitors of AKT. Studies of linker strand-binding adenine isosteres identified SAR trends in potency and selectivity that were consistent with binding interactions observed in structures of the inhibitors bound to AKT1 and to the counter-screening target PKA. One compound was shown to have acceptable pharmacokinetic properties and to be a potent inhibitor of AKT signaling and of in vivo xenograft tumor growth in a preclinical model of glioblastoma.
Subject(s)
Antineoplastic Agents/chemistry , Azoles/chemistry , Neoplasms/drug therapy , Protein Kinase Inhibitors/chemistry , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Animals , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/therapeutic use , Azoles/pharmacokinetics , Azoles/therapeutic use , Binding Sites , Crystallography, X-Ray , Cyclic AMP-Dependent Protein Kinases/antagonists & inhibitors , Cyclic AMP-Dependent Protein Kinases/metabolism , Cyclin-Dependent Kinase 2/antagonists & inhibitors , Cyclin-Dependent Kinase 2/metabolism , Drug Design , Mice , Mice, Nude , Protein Kinase Inhibitors/pharmacokinetics , Protein Kinase Inhibitors/therapeutic use , Proto-Oncogene Proteins c-akt/metabolism , Rats , Rats, Sprague-Dawley , Structure-Activity Relationship , Xenograft Model Antitumor AssaysABSTRACT
A 2-aminothiazole derivative 1 was developed as a potential inhibitor of the oncology target AKT, a serine/threonine kinase. When incubated in rat and human liver microsomes in the presence of NADPH, 1 underwent significant metabolic activation on its 2-aminothiazole ring, leading to substantial covalent protein binding. Upon addition of glutathione, covalent binding was reduced significantly, and multiple glutathione adducts were detected. Novel metabolites from the in vitro incubates were characterized by LC-MS and NMR to discern the mechanism of bioactivation. An in silico model was developed based on the proposed mechanism and was employed to predict bioactivation in 23 structural analogues. The predictions were confirmed empirically for the bioactivation liability, in vitro, by LC-MS methods screening for glutathione incorporation. New compounds were identified with a low propensity for bioactivation.
Subject(s)
Cytochrome P-450 Enzyme System/metabolism , Glutathione/metabolism , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Thiazoles/adverse effects , Thiazoles/chemistry , Animals , Epoxy Compounds/metabolism , Humans , Microsomes, Liver/drug effects , Microsomes, Liver/metabolism , Models, Biological , Molecular Structure , Rats , Thiazoles/metabolismABSTRACT
A series of compounds containing the 2-amino-1,3-thiazol-4(5H)-one core were found to be potent inhibitors of the enzyme 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1). One of our lead compounds from this series activated the human nuclear xenobiotic receptor, pregnane X receptor (PXR). To try and mitigate the PXR activity, we prepared analogues of our lead series that contained polar groups on the right-hand side of the thiazolone. Several analogues containing amides or alcohols appended to the C-5 position of the thiazolone showed a significant reduction in PXR activity. Through these structure-activity efforts, a compound containing a tert-alcohol group off the C-5 position, analogue (S)-33a, was found to have an 11beta-HSD1 Ki = 35 nM and negligible PXR activity. Compound (S)-33a was advanced into a pharmacodynamic model in cynomolgus monkeys, where it inhibited adipose 11beta-HSD1 activity after being orally administered.
Subject(s)
11-beta-Hydroxysteroid Dehydrogenase Type 1/antagonists & inhibitors , Enzyme Inhibitors/pharmacology , Receptors, Steroid/metabolism , 11-beta-Hydroxysteroid Dehydrogenase Type 1/chemistry , Animals , Chemistry, Pharmaceutical/methods , Crystallography, X-Ray/methods , Cytochrome P-450 CYP3A/chemistry , Drug Design , Humans , Kinetics , Macaca fascicularis , Male , Models, Molecular , Molecular Conformation , Pregnane X Receptor , Tissue DistributionABSTRACT
Malonyl-CoA decarboxylase (MCD) catalyzes the conversion of malonyl-CoA to acetyl-CoA and thereby regulates malonyl-CoA levels in cells. Malonyl-CoA is a potent inhibitor of mitochondrial carnitine palmitoyltransferase-1, a key enzyme involved in the mitochondrial uptake of fatty acids for oxidation. Abnormally high rates of fatty acid oxidation contribute to ischemic damage. Inhibition of MCD leads to increased malonyl-CoA and therefore decreases fatty acid oxidation, representing a novel approach for the treatment of ischemic heart injury. The commonly used MCD assay monitors the production of NADH fluorometrically, which is not ideal for library screening due to potential fluorescent interference by certain compounds. Here we report a luminescence assay for MCD activity. This assay is less susceptible to fluorescent interference by compounds. Furthermore, it is 150-fold more sensitive, with a detection limit of 20 nM acetyl-CoA, compared to 3 muM in the fluorescence assay. This assay is also amenable to automation for high-throughput screening and yields excellent assay statistics (Z' > 0.8). In addition, it can be applied to the screening for inhibitors of any other enzymes that generate acetyl-CoA.
Subject(s)
Carboxy-Lyases/analysis , Luminescence , Luminescent Measurements/methods , Carboxy-Lyases/genetics , Carboxy-Lyases/metabolism , Chromatography, High Pressure Liquid/methods , Fluorescence , Humans , Kinetics , Recombinant Proteins/analysis , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Reproducibility of ResultsABSTRACT
A series of 2-anilinothiazolones were prepared as inhibitors of 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1). The most potent compounds contained a 2-chloro or 2-fluoro group on the aniline ring with an isopropyl substituent on the 5-position of the thiazolone ring (compounds 2 and 3, respectively). The binding mode was determined through the X-ray co-crystal structure of the enzyme with compound 3. This compound was also approximately 70-fold selective over 11beta-HSD2 and was orally bioavailable in rat pharmacokinetic studies. However, compound 3 was >580-fold less active in the 11beta-HSD1 cell assay when tested in the presence of 3% human serum albumin.
Subject(s)
11-beta-Hydroxysteroid Dehydrogenase Type 1/antagonists & inhibitors , Thiazoles/chemistry , Thiazoles/pharmacology , 11-beta-Hydroxysteroid Dehydrogenase Type 1/chemistry , Animals , CHO Cells , Chlorine/chemistry , Cricetinae , Cricetulus , Crystallography, X-Ray , Fluorine/chemistry , Humans , Molecular Structure , Rats , Structure-Activity Relationship , Thiazoles/classificationABSTRACT
Inhibition of tumor-induced angiogenesis is a promising strategy in anticancer research. Neovascularization is a process required for both tumor growth and metastasis. Enhanced understanding of the underlying molecular mechanisms has led to the discovery of a variety of pharmaceutically attractive targets. Decades of investigation suggest that vascular endothelial growth factor (VEGF) and its receptors, in particular VEGFR2 or kinase insert-domain-containing receptor (Kdr), play a critical role in the growth and survival of endothelial cells in newly forming vasculature. The clinical utility of inhibitors of this receptor tyrosine kinase is currently under intense investigation. Herein we report our efforts in this arena.
Subject(s)
Niacinamide/pharmacology , Protein Kinase Inhibitors/pharmacology , Vascular Endothelial Growth Factor Receptor-2/antagonists & inhibitors , Cell Line, Tumor , HumansABSTRACT
The bradykinin B1 receptor is induced following tissue injury and/or inflammation. Antagonists of this receptor have been studied as promising candidates for treatment of chronic pain. We have identified aryl sulfonamides containing a chiral chroman diamine moiety that are potent antagonists of the human B1 receptor. Our previously communicated lead, compound 2, served as a proof-of-concept molecule, but suffered from poor pharmacokinetic properties. With guidance from metabolic profiling, we performed structure-activity relationship studies and have identified potent analogs of 2. Variation of the sulfonamide moiety revealed a preference for 3- and 3,4-disubstituted aryl sulfonamides, while bulky secondary and tertiary amines were preferred at the benzylic amine position for potency at the B1 receptor. Modifying the beta-amino acid core of the molecule lead to the discovery of highly potent compounds with improved in vitro pharmacokinetic properties. The most potent analog at the human receptor, compound 38, was also active in a rabbit B1 receptor cellular assay. Furthermore, compound 38 displayed in vivo activity in two rabbit models, a pharmacodynamic model with a blood pressure readout and an efficacy model of inflammatory pain.
Subject(s)
Amides/chemical synthesis , Analgesics/chemical synthesis , Benzopyrans/chemical synthesis , Bradykinin B1 Receptor Antagonists , Chromans/chemical synthesis , Sulfonamides/chemical synthesis , Amides/pharmacokinetics , Amides/pharmacology , Analgesics/pharmacokinetics , Analgesics/pharmacology , Animals , Benzopyrans/pharmacokinetics , Benzopyrans/pharmacology , Blood Pressure/drug effects , CHO Cells , Calcium/metabolism , Chromans/pharmacokinetics , Chromans/pharmacology , Cricetinae , Cricetulus , Humans , In Vitro Techniques , Inflammation/drug therapy , Male , Microsomes/metabolism , Pain/drug therapy , Rabbits , Rats , Rats, Sprague-Dawley , Receptor, Bradykinin B1/agonists , Stereoisomerism , Structure-Activity Relationship , Sulfonamides/pharmacokinetics , Sulfonamides/pharmacologyABSTRACT
11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) is the enzyme that converts cortisone to cortisol. A growing body of evidence suggests that selective inhibition of 11beta-HSD1 could potentially treat metabolic syndrome as well as type 2 diabetes. Through modification of our initial lead 1, we have discovered trifluoromethyl thiazolone 17. This compound had a Ki of 22 nM, possessed low in vivo clearance, and showed a 91% inhibition of adipose 11beta-HSD1 enzymatic activity in a mouse ex vivo pharmacodynamic model.