Discovery of 3-Cyano-N-(3-(1-isobutyrylpiperidin-4-yl)-1-methyl-4-(trifluoromethyl)-1H-pyrrolo[2,3-b]pyridin-5-yl)benzamide. A Potent, Selective, and Orally Bioavailable Retinoic Acid Receptor-Related Orphan Receptor C2 (RORC2) Inverse Agonist (original) (raw)

Discovery of 3-Cyano-N-(3-(1-isobutyrylpiperidin-4-yl)-1-methyl-4-(trifluoromethyl)-1H-pyrrolo[2,3-b]pyridin-5-yl)benzamide: A Potent, Selective, and Orally Bioavailable Retinoic Acid Receptor-Related Orphan Receptor C2 Inverse Agonist

Journal of Medicinal Chemistry

The nuclear hormone receptor retinoic acid receptor-related orphan C2 (RORC2, also known as RORγt) is a promising target for the treatment of autoimmune diseases. A small molecule, inverse agonist of the receptor is anticipated to reduce production of IL-17, a key proinflammatory cytokine. Through a high-throughput screening approach, we identified a molecule displaying promising binding affinity for RORC2, inhibition of IL-17 production in Th17 cells, and selectivity against the related RORA and RORB receptor isoforms. Lead optimization to improve the potency and metabolic stability of this hit focused on two key design strategies, namely, iterative optimization driven by increasing lipophilic efficiency and structure-guided conformational restriction to achieve optimal ground state energetics and maximize receptor residence time. This approach successfully identified 3-cyano-N-(3-(1-isobutyrylpiperidin-4-yl)-1-methyl-4-(trifluoromethyl)-1H-pyrrolo[2,3-b]pyridin-5-yl)benzamide as a potent and selective RORC2 inverse agonist, demonstrating good metabolic stability, oral bioavailability, and the ability to reduce IL-17 levels and skin inflammation in a preclinical in vivo animal model upon oral administration.

Structure-based design leads to potent and orally bioavailable inverse agonists of ROR gamma t

Journal of Medicinal Chemistry, 2018

Retinoic acid receptor-related orphan receptor γt (RORγt), has been identified as the master regulator of T H 17 cell function and development, making it an attractive target for the treatment of autoimmune diseases by a small molecule approach. Herein we describe our investigations on a series of 4-aryl-thienyl acetamides, which were guided by insights from Xray co-crystal structures. Efforts in targeting the co-factor recruitment site from the 4-aryl group on the thiophene led to a series of potent binders, with nanomolar activity in a primary human T H 17 cell assay. The observation of a molecule of DMSO binding in a sub-pocket outside the LBD inspired the introduction of an acetamide into the benzylic position of these compounds. Hereby, a hydrogen bond interaction of the introduced acetamide oxygen with the backbone amide of Glu379 was established. This greatly enhanced the cellular activity of previously weakly cell active compounds. The best compounds combined potent inhibition of IL-17 release with favorable PK in rodents with compound 32 representing a promising starting point for future investigations.

Structural studies unravel the active conformation of apo RORγt nuclear receptor and a common inverse agonism of two diverse classes of RORγt inhibitors

The Journal of biological chemistry, 2017

The nuclear receptor retinoid acid-related orphan receptor γt (RORγt) is a master regulator of the Th17/IL-17 pathway that plays crucial roles in the pathogenesis of autoimmunity. RORγt has recently emerged as a highly promising target for treatment of a number of autoimmune diseases. Through high-throughput screening we previously identified several classes of inverse agonists for RORγt. Here, we report the crystal structures for the ligand binding domain of RORγt in both apo and ligand-bound states. We show that apo RORγt adopts an active conformation capable of recruiting coactivator peptides and present a detailed analysis of the structural determinants that stabilize helix 12 (H12) of RORγt in the active state in the absence of a ligand. The structures of ligand-bound RORγt reveal that binding of the inverse agonists disrupts critical interactions that stabilize H12. This destabilizing effect is supported by ab initio calculations and experimentally by a normalized crystallogra...

Identification of a novel selective inverse agonist probe and analogs for the Retinoic acid receptor-related Orphan Receptor Gamma (RORγ)

Several nuclear receptors (NRs) are still characterized as orphan receptors because endogenous ligands have not yet been identified for these proteins. Evidence is growing suggesting the retinoic acid receptor-related orphan receptors (RORs) bind to, and are modulated by oxysterols. Recently, we discovered that the synthetic LXRα agonist T0901317 (ML125) was a potent inverse agonist of RORα and RORγ. Structure activity relationship (SAR) studies quickly revealed a strategy to remove the LXRα activity from the ML125 chemical scaffold which led to ML124. ML124 represented the first synthetic RORα/RORγ dual inverse agonist devoid of LXRα activity. While there appear to be clear non-overlapping roles for RORα and RORγ, chemical probes that are isoform selective are needed to dissect this biology. We described the identification of a selective RORα synthetic ligand, ML176, which directly binds to RORα, but not other RORs, and functions as a selective inverse agonist of RORα in cell-based...

Faculty of 1000 evaluation for Crystal structures of the nuclear receptor, liver receptor homolog 1, bound to synthetic agonists

F1000 - Post-publication peer review of the biomedical literature

Edited by Norma Allewell Liver receptor homolog 1 (NR5A2, LRH-1) is an orphan nuclear hormone receptor that regulates diverse biological processes, including metabolism, proliferation, and the resolution of endoplasmic reticulum stress. Although preclinical and cellular studies demonstrate that LRH-1 has great potential as a therapeutic target for metabolic diseases and cancer, development of LRH-1 modulators has been difficult. Recently, systematic modifications to one of the few known chemical scaffolds capable of activating LRH-1 failed to improve efficacy substantially. Moreover, mechanisms through which LRH-1 is activated by synthetic ligands are entirely unknown. Here, we use x-ray crystallography and other structural methods to explore conformational changes and receptor-ligand interactions associated with LRH-1 activation by a set of related agonists. Unlike phospholipid LRH-1 ligands, these agonists bind deep in the pocket and do not interact with residues near the mouth nor do they expand the pocket like phospholipids. Unexpectedly, two closely related agonists with similar efficacies (GSK8470 and RJW100) exhibit completely different binding modes. The dramatic repositioning is influenced by a differential ability to establish stable face-to-face-stacking with the LRH-1 residue His-390, as well as by a novel polar interaction mediated by the RJW100 hydroxyl group. The differing binding modes result in distinct mechanisms of action for the two agonists. Finally, we identify a network of conserved water molecules near the ligand-binding site that are important for activation by both agonists. This work reveals a previously unappreciated complexity associated with LRH-1 agonist development and offers insights into rational design strategies.

Adamantyl-substituted retinoid-derived molecules that interact with the orphan nuclear receptor small heterodimer partner: effects of replacing the 1-adamantyl or …

Journal of medicinal …, 2008

Protein tyrosine phosphatases (PTPs) play vital roles in numerous cellular processes and are implicated in a growing number of human diseases, ranging from cancer to cardiovascular, immunological, infectious, neurological, and metabolic diseases. Here we present methods for developing small molecule inhibitors for these enzymes, starting with how to set up a high throughput chemical library screening for PTP inhibitors, how to confirm and prioritize hits, and how to circumnavigate possible pitfalls. Next, we present the relatively new hit generating method of in silico or virtual screening. We give an overview of existing software tools, describe how to choose and generate protein target structures and illustrate the procedure with examples. We then discuss how three-dimensional PTP structures can be analyzed in terms of their potential to bind small molecule inhibitors selectively over homologous proteins and how computer tools can be applied for lead optimization efforts. We finish with a perspective of how well these PTP inhibitors might perform as future drugs to treat human disease.

Discovery of Potent, Orally Bioavailable Small-Molecule Inhibitors of the Human CCR2 Receptor

ChemMedChem, 2008

WNT signaling is frequently deregulated in malignancy, particularly in colon cancer, and plays a key role in the generation and maintenance of cancer stem cells. We report the discovery and optimization of a 3,4,5-trisubstituted pyridine 9 using a high-throughput cell-based reporter assay of WNT pathway activity. We demonstrate a twisted conformation about the pyridine−piperidine bond of 9 by small-molecule X-ray crystallography. Medicinal chemistry optimization to maintain this twisted conformation, cognisant of physicochemical properties likely to maintain good cell permeability, led to 74 (CCT251545), a potent small-molecule inhibitor of WNT signaling with good oral pharmacokinetics. We demonstrate inhibition of WNT pathway activity in a solid human tumor xenograft model with evidence for tumor growth inhibition following oral dosing. This work provides a successful example of hypothesis-driven medicinal chemistry optimization from a singleton hit against a cellbased pathway assay without knowledge of the biochemical target.

Ternary crystal structure of human RORγ ligand-binding-domain, an inhibitor and corepressor peptide provides a new insight into corepressor interaction

Scientific Reports, 2018

Retinoic acid-related orphan receptor gamma (RORγ) plays pivotal roles in autoimmune diseases by controlling the lineage of interleukin 17 (IL-17)-producing CD4+ T cells (Th17 cells). Structure-based drug design has proven fruitful in the development of inhibitors targeting the ligand binding domain (LBD) of RORγ. Here, we present the crystal structure of a novel RORγ inhibitor co-complex, in the presence of a corepressor (CoR) peptide. This ternary complex with compound T reveals the structural basis for an inhibitory mechanism different from the previously reported inverse agonist. Compared to the inverse agonist, compound T induces about 2 Å shift of helix 5 (H5) backbone and side-chain conformational changes of Met365 on H5. These conformational changes correlate to reduced CoR peptide binding to RORγ-LBD in the presence of compound T, which suggests that the shift of H5 is responsible. This crystal structure analysis will provide useful information for the development of novel ...

Rational design of RAR-selective ligands revealed by RARβ crystal stucture

Embo Reports, 2004

The crystal structure of the ligand-binding domain of RARb, a suspect tumour suppressor, reveals important features that distinguish it from the two other RAR isotypes. The most striking difference is an extra cavity allowing RARb to bind more bulky agonists. Accordingly, we identified a ligand that shows RARb selectivity with a 100-fold higher affinity to RARb than to a or c isotypes. The structural differences between the three RAR ligand-binding pockets revealed a rationale explaining how a single retinoid can be at the same time an RARa, c antagonist and an RARb agonist. In addition, we demonstrate how to generate an RARb antagonist by gradually modifying the bulkiness of a single substitution. Together, our results provide structural guidelines for the synthesis of RARb-selective agonists and antagonists, allowing for the first time to address pharmacologically the tumour suppressor role of RARb in vitro and in animal models.

Crystal Structures of the Nuclear Receptor, Liver Receptor Homolog 1, Bound to Synthetic Agonists

Journal of Biological Chemistry, 2016

Edited by Norma Allewell Liver receptor homolog 1 (NR5A2, LRH-1) is an orphan nuclear hormone receptor that regulates diverse biological processes, including metabolism, proliferation, and the resolution of endoplasmic reticulum stress. Although preclinical and cellular studies demonstrate that LRH-1 has great potential as a therapeutic target for metabolic diseases and cancer, development of LRH-1 modulators has been difficult. Recently, systematic modifications to one of the few known chemical scaffolds capable of activating LRH-1 failed to improve efficacy substantially. Moreover, mechanisms through which LRH-1 is activated by synthetic ligands are entirely unknown. Here, we use x-ray crystallography and other structural methods to explore conformational changes and receptor-ligand interactions associated with LRH-1 activation by a set of related agonists. Unlike phospholipid LRH-1 ligands, these agonists bind deep in the pocket and do not interact with residues near the mouth nor do they expand the pocket like phospholipids. Unexpectedly, two closely related agonists with similar efficacies (GSK8470 and RJW100) exhibit completely different binding modes. The dramatic repositioning is influenced by a differential ability to establish stable face-to-face-stacking with the LRH-1 residue His-390, as well as by a novel polar interaction mediated by the RJW100 hydroxyl group. The differing binding modes result in distinct mechanisms of action for the two agonists. Finally, we identify a network of conserved water molecules near the ligand-binding site that are important for activation by both agonists. This work reveals a previously unappreciated complexity associated with LRH-1 agonist development and offers insights into rational design strategies.