Olivier René

Room-temperature direct arylation of polyfluorinated arenes under biphasic conditions.

New biphasic conditions for the palladium-catalyzed direct arylation of electron-poor fluorinated arenes have been developed. Taking advantage of biphasic chemistry, the use of an immiscible mixture of water and an organic solvent allows complete solubilization of all components of the system, enabling the reaction to proceed at room temperature in yields up to 99%.

Domino Palladium-Catalyzed Heck-Intermolecular Direct Arylation Reactions

A domino palladium-catalyzed Heck-intermolecular direct arylation reaction has been developed, giving access to a variety of dihydrobenzofurans, indolines, and oxindoles. A variety of sulfur-containing heterocycles such as thiazoles, thiophenes, and benzothiophene can be employed as the direct arylation coupling partner in yields up to 99%.

Structure-based design of substituted hexafluoroisopropanol-arylsulfonamides as modulators of RORc.

The structure-activity relationships of T0901317 analogs were explored as RORc inverse agonists using the principles of property- and structure-based drug design. An X-ray co-crystal structure of T0901317 and RORc was obtained and provided molecular insight into why T0901317 functioned as an inverse agonist of RORc; whereas, the same ligand functioned as an agonist of FXR, LXR, and PXR. The structural data was also used to design inhibitors with improved RORc biochemical and cellular activities. The improved inhibitors possessed enhanced selectivity profiles (rationalized using the X-ray crystallographic data) against other nuclear receptors.

Minor Structural Change to Tertiary Sulfonamide RORc Ligands Led to Opposite Mechanisms of Action.

A minor structural change to tertiary sulfonamide RORc ligands led to distinct mechanisms of action. Co-crystal structures of two compounds revealed mechanistically consistent protein conformational changes. Optimized phenylsulfonamides were identified as RORc agonists while benzylsulfonamides exhibited potent inverse agonist activity. Compounds behaving as agonists in our biochemical assay also gave rise to an increased production of IL-17 in human PBMCs whereas inverse agonists led to significant suppression of IL-17 under the same assay conditions. The most potent inverse agonist compound showed >180-fold selectivity over the ROR isoforms as well as all other nuclear receptors that were profiled.

Reduction in lipophilicity improved the solubility, plasma-protein binding, and permeability of tertiary sulfonamide RORc inverse agonists.

Using structure-based drug design principles, we identified opportunities to reduce the lipophilicity of our tertiary sulfonamide RORc inverse agonists. The new analogs possessed improved RORc cellular potencies with >77-fold selectivity for RORc over other nuclear receptors in our cell assay suite. The reduction in lipophilicity also led to an increased plasma-protein unbound fraction and improvements in cellular permeability and aqueous solubility.

Discovery of 1-{4-[3-Fluoro-4-((3S,6R)-3-methyl-1,1-dioxo-6-phenyl-[1,2]thiazinan-2-ylmethyl)-phenyl]-piperazin-1-yl}-ethanone (GNE-3500): a Potent, Selective, and Orally Bioavailable Retinoic Acid Receptor-Related Orphan Receptor C (RORc or RORγ) Inverse Agonist

Retinoic acid receptor-related orphan receptor C (RORc, RORγ, or NR1F3) is a nuclear receptor that plays a major role in the production of interleukin (IL)-17. Considerable efforts have been directed toward the discovery of selective RORc inverse agonists as potential treatments of inflammatory diseases such as psoriasis and rheumatoid arthritis. Using the previously reported tertiary sulfonamide 1 as a starting point, we engineered structural modifications that significantly improved human and rat metabolic stabilities while maintaining a potent and highly selective RORc inverse agonist profile. The most advanced δ-sultam compound, GNE-3500 (27, 1-{4-[3-fluoro-4-((3S,6R)-3-methyl-1,1-dioxo-6-phenyl-[1,2]thiazinan-2-ylmethyl)-phenyl]-piperazin-1-yl}-ethanone), possessed favorable RORc cellular potency with 75-fold selectivity for RORc over other ROR family members and >200-fold selectivity over 25 additional nuclear receptors in a cell assay panel. The favorable potency, selectivity, in vitro ADME properties, in vivo PK, and dose-dependent inhibition of IL-17 in a PK/PD model support the evaluation of 27 in preclinical studies.

Identification of tertiary sulfonamides as RORc inverse agonists.

Screening a nuclear receptor compound subset in a RORc biochemical binding assay revealed a benzylic tertiary sulfonamide hit. Herein, we describe the identification of compounds with improved RORc biochemical inverse agonist activity and cellular potencies. These improved compounds also possessed appreciable selectivity for RORc over other nuclear receptors.

A reversed sulfonamide series of selective RORc inverse agonists.

The identification of a new series of RORc inverse agonists is described. Comprehensive structure-activity relationship studies of this reversed sulfonamide series identified potent RORc inverse agonists in biochemical and cellular assays which were also selective against a panel of nuclear receptors. Our work has contributed a compound that may serve as a useful in vitro tool to delineate the complex biological pathways involved in signalling through RORc. An X-ray co-crystal structure of an analogue with RORc has also provided useful insights into the binding interactions of the new series.

Palladium-catalyzed α-arylation of sultams with aryl and heteroaryl iodides.

Palladium(0)-catalyzed conditions for the α-arylation of sultams with aryl and heteroaryl iodides have been developed. Arylation of 3-substituted 1,3-propanesultams gave rise to high yields and high diastereomeric ratios, leading to the thermodynamically favored cis product. The arylation was broadly applicable to various electron-rich and electron-poor (hetero)aromatic iodides.

Palladium-Catalyzed Ring Expansion of Spirocyclopropanes to Form Caprolactams and Azepanes.

A palladium(0)-catalyzed rearrangement of piperidones and piperidines bearing a spirocyclopropane ring was developed. The ring expansion reaction led to a variety of functionalized caprolactam and azepane products in good to excellent yields. Experimental and computational mechanistic studies revealed an initial oxidative addition of the distal carbon-carbon bond of a cyclopropane ring to the palladium(0) catalyst and the relief of ring strain as a driving force for product formation.