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The HTS-based discovery and structure-guided optimization of a novel series of GKRP-selective GK-GKRP disrupters are revealed. Diarylmethanesulfonamide hit 6 (hGK-hGKRP IC50 = 1.2 µM) was optimized to lead compound 32 (AMG-0696; hGK-hGKRP IC50 = 0.0038 µM). A stabilizing interaction between a nitrogen atom lone pair and an aromatic sulfur system (nN → s*S-X) in 32 was exploited to conformationally constrain a biaryl linkage and allow contact with key residues in GKRP. Lead compound 32 was shown to induce GK translocation from the nucleus to the cytoplasm in rats (IHC score = 0; 10 mg/kg po, 6 h) and blood glucose reduction in mice (POC = -45%; 100 mg/kg po, 3 h). X-ray analyses of 32 and several precursors bound to GKRP were also obtained. This novel disrupter of GK-GKRP binding enables further exploration of GKRP as a potential therapeutic target for type II diabetes and highlights the value of exploiting unconventional nonbonded interactions in drug design. [ABSTRACT FROM AUTHOR]

Abstract: In a series of bradykinin B1 antagonists, we discovered that replacement of oxopiperazine acetamides with dehydro-oxopiperazine acetamides provided compounds with enhanced activity against the B1 receptor. The synthesis and SAR leading to potent analogs with reduced molecular weight will be discussed. [Copyright &y& Elsevier]

Abstract: Through the analysis of X-ray crystallographic information and previous SAR studies, a novel series of protein kinase B (PKB/AKT) inhibitors was developed. The compounds showed nanomolar inhibition of AKT1 and were selective against cyclin-dependent kinase 2 (CDK2). [Copyright &y& Elsevier]

Abstract: A bis-amide antagonist of Smoothened, a seven-transmembrane receptor in the Hedgehog signaling pathway, was discovered via high throughput screening. In vitro and in vivo experiments demonstrated that the bis-amide was susceptible to N-acyl transferase mediated amide scission. Several bioisosteric replacements of the labile amide that maintained in vitro potency were identified and shown to be metabolically stable in vitro and in vivo. [Copyright &y& Elsevier]

Abstract: The discovery of novel and highly potent oxopiperazine based B1 receptor antagonists is described. Compared to the previously described arylsulfonylated (R)-3-amino-3-phenylpropionic acid series, the current compounds showed improved in vitro potency and metabolic stability. Compound 17, 2-((2R)-1-((4-methylphenyl)sulfonyl)-3-oxo-2-piperazinyl)-N-((1R)-6-(1-piperidinylmethyl)-1,2,3,4-tetrahydro-1-naphthalenyl)acetamide, showed EC50 of 10.3nM in a rabbit biochemical challenge model. The practical syntheses of chiral arylsulfonylated oxopiperazine acetic acids are also described. [Copyright &y& Elsevier]

Abstract: The synthesis and SAR of a series of 4,4-disubstituted cyclohexylbenzamide inhibitors of 11β-HSD1 are described. Optimization rapidly led to potent, highly selective, and orally bioavailable inhibitors demonstrating efficacy in both rat and non-human primate ex vivo pharmacodynamic models. [Copyright &y& Elsevier]

Abstract: Pyridopyridazine antagonists of the hedgehog signaling pathway are described. Designed to optimize our previously described phthalazine smoothened antagonists, a representative compound eliminates a PXR liability while retaining potency and in vitro metabolic stability. Moreover, the compound has improved efficacy in a hedgehog/smoothened signaling mouse pharmacodynamic model. [Copyright &y& Elsevier]

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 IC50 =1.3nM for compound 16). Some of these compounds showed modest oral bioavailability in rats. [Copyright &y& Elsevier]

Abstract: The Hedgehog (Hh) signaling pathway regulates cell proliferation and differentiation in developing tissues, and abnormal activation of the Hh pathway has been linked to several tumor subsets. As a transducer of Hh signaling, the GPCR-like protein Smoothened (Smo) is a promising target for disruption of unregulated Hh signaling. A series of 1-amino-4-arylphthalazines was developed as potent and orally bioavailable inhibitors of Smo. A representative compound from this class demonstrated significant tumor volume reduction in a mouse medulloblastoma model. [Copyright &y& Elsevier]

Abstract: A series of 2-aminothiadiazole of inhibitors of AKT1 is described. SAR relationships are discussed, along with selectivity for protein kinase A (PKA) and cyclin-dependent kinase 2 (CDK2). Moderate selectivity observed in several compounds for AKT1 versus PKA is rationalized by X-ray crystallographic analysis. Key compounds showed activity in cellular assays measuring phosphorylation of two AKT substrates, PRAS40 and FKHRL1. Compound 30 was advanced to a mouse liver PD assay, where it showed dose-dependent inhibition of AKT activity, as measured by the inhibition of phospho-PRAS40. [Copyright &y& Elsevier]

Abstract: Discovery and optimization of a piperidyl benzamide series of 11β-HSD1 inhibitors is described. This series was derived from a cyclohexyl benzamide lead structures to address PXR selectivity, high non-specific protein binding, poor solubility, limited in vivo exposure, and in vitro cytotoxicity issues observed with the cyclohexyl benzamide structures. These efforts led to the discovery of piperidyl benzamide 15 which features improved properties over the cyclohexyl benzamide derivatives. [Copyright &y& Elsevier]

Abstract: Novel 4,4-disubstituted cyclohexylbenzamide inhibitors of 11β-HSD1 were optimized to account for liabilities relating to in vitro pharmacokinetics, cytotoxicity and protein-related shifts in potency. A representative compound showing favorable in vivo pharmacokinetics was found to be an efficacious inhibitor of 11β-HSD1 in a rat pharmacodynamic model (ED50 =10mg/kg). [Copyright &y& Elsevier]

Abstract: We report the structure-based design and synthesis of a novel series of aza-benzimidazoles as PHD2 inhibitors. These efforts resulted in compound 22, which displayed highly potent inhibition of PHD2 function in vitro. [Copyright &y& Elsevier]

Abstract: We report the development of aryl sulfones as Bradykinin B1 receptor antagonists. Variation of the linker region identified diol 23 as a potent B1 antagonist, while modifications of the aryl moiety led to compound 26, both of which were efficacious in rabbit biochemical challenge and pain models. [Copyright &y& Elsevier]

Abstract: Replacement of the core β-amino acid in our previously reported piperidine acetic acid and β-phenylalanine-based Bradykinin B1 antagonists by dihydroquinoxalinone acetic acid increases the in vitro potency and metabolic stability. The most potent compounds from this series have IC50s<0.2nM in a human B1 receptor functional assay. A molecular modeling study of the binding modes of key compounds, based on a B1 homology model, explains the structure–activity relationship (SAR) for these analogs. [Copyright &y& Elsevier]

Abstract: A potent and selective c-Kit inhibitor 20 was identified through a structure–activity relationship study. In an in vivo mouse model of mast cell activation, 20 blocked the SCF-induced histamine release with an EC50 of 26nM. [Copyright &y& Elsevier]

Abstract: Inhibition of the PHD2 enzyme has been associated with increased red blood cell levels. From a screening hit, a series of novel hydroxyl-thiazoles were developed as potent PHD2 inhibitors. [Copyright &y& Elsevier]

Abstract: The LPA2 protein is overexpressed in many tumor cells. We report the optimization of a series of LPA2 antagonists using calcium mobilization assay (aequorin assay) that led to the discovery of the first reported inhibitors selective for LPA2. Key compounds were evaluated in vitro for inhibition of LPA2 mediated Erk activation and proliferation of HCT-116 cells. These compounds could be used to evaluate the benefits of LPA2 inhibition both in vitro and in vivo. [Copyright &y& Elsevier]

Abstract: We report the development of the novel N-substituted benzimidazole 11 as a potent and selective human formyl peptide receptor-like 1 (hFPRL1) agonist. This compound and its less active enantiomer 12 were identified as useful tools for studying receptor function in vitro. [Copyright &y& Elsevier]

Abstract: A series of 2-anilinothiazolones were prepared as inhibitors of 11β-hydroxysteroid dehydrogenase type 1 (11β-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 ∼70-fold selective over 11β-HSD2 and was orally bioavailable in rat pharmacokinetic studies. However, compound 3 was >580-fold less active in the 11β-HSD1 cell assay when tested in the presence of 3% human serum albumin. [Copyright &y& Elsevier]

Abstract: Ullmann ether synthesis was conducted on a variety of chloro-heterocycles with different phenols using optimized conditions involving copper powder and cesium carbonate. On many substrates, microwave heating afforded higher yields in significantly shorter reaction times compared to conventional heating conditions. These findings provide a facile method for aryl ether synthesis from chloropyridines, chloroquinolines, and chlorobenzothiazoles. [Copyright &y& Elsevier]

Abstract: We report the discovery of potent agonists for the human formyl-peptide-like 1 receptor (hFPRL1). These compounds did not act at a closely related receptor denoted human formyl peptide receptor (hFPR) up to 10μM concentration. Recent studies have indicated that agonizing this receptor may promote resolution of inflammation. In an exploratory study, a novel hFPRL1 agonist showed efficacy in a mouse ear inflammation model following oral administration. [Copyright &y& Elsevier]

Abstract: A thiazole derivative, 2-(2,6-dichlorobenzyl)-N-(4-isopropylphenyl) thiazole-4-carboxamide (1), was identified as a TRPV1 antagonist. We synthesized various thiazole analogs and evaluated them for their ability to block capsaicin- or acid-induced calcium influx in TRPV1-expressing CHO cells. The IC50 values of the most potent antagonists were ca. 0.050μM in these assays. [Copyright &y& Elsevier]

Abstract: A regio-specific synthesis of N-substituted imidazoles is described. Readily available α-amino acids are converted to α-aminocarbonyl derivatives and reacted with various isothiocyanates to give N-substituted cyclic thioureas. Oxidative or reductive desulfurization of the cyclic thioureas affords structurally diversified imidazoles in good to excellent yields. [Copyright &y& Elsevier]

Abstract: Novel potent trisubstituted pyridazine inhibitors of p38 MAP (mitogen activated protein) kinase are described that have activity in both cell-based assays of cytokine release and animal models of rheumatoid arthritis. They demonstrated potent inhibition of LPS-induced TNF-α production in mice and exhibited good efficacy in the rat collagen induced arthritis model. [Copyright &y& Elsevier]

1,5-Diarylbenzimidazoles have been identified as potent inhibitors of KDR kinase activity. The series was developed with a goal of finding compounds with optimal drug-like properties. This communication describes structural modifications in the series that enhance solubility, lower protein binding, and provide compounds with excellent potency and pharmacokinetic profiles. [Copyright &y& Elsevier]

Abstract: Deregulation of the receptor tyrosine kinase c-Kit is associated with an increasing number of human diseases, including certain cancers and mast cell diseases. Interference of c-Kit signaling with multi-kinase inhibitors has been shown clinically to successfully treat gastrointestinal stromal tumors and mastocytosis. Targeted therapy of c-Kit activity may provide therapeutic advantages against off-target effects for non-oncology applications. A new structural class of c-Kit inhibitors is described, including in vitro c-Kit potency, kinase selectivity, and the observed binding mode. [Copyright &y& Elsevier]

Abstract: An efficient synthetic route to 1,6- and 1,7-dibromo-3-aminoisoquinoline was devised. These intermediates served as ideal templates for the preparation of 3-aminoisoquinoline analogues functionalized at C(6) or C(7). [Copyright &y& Elsevier]

A novel synthetic method to introduce a carbon&z.sbnd;carbon bond at the 2-position of pyrimidinones via nucleophilic addition of Grignard reagents to 2-cyano pyrimidinones at ambient conditions is disclosed. This unique approach leads to the preparation of such biologically important molecules as polysubstituted pyrimidinones in good to excellent yields. [Copyright &y& Elsevier]