Discovery of (R,E)-N-(7-Chloro-1-(1-[4-(dimethylamino)but-2-enoyl]azepan-3-yl)-1H-benzo[d]imidazol-2-yl)-2-methylisonicotinamide (EGF816), a Novel, Potent, and WT Sparing Covalent Inhibitor of Oncogenic (L858R, ex19del) and Resistant (T790M) EGFR Mutants for the Treatment of EGFR Mutant Non-Small-Cell Lung Cancers.

Over the past decade, first and second generation EGFR inhibitors have significantly improved outcomes for lung cancer patients with activating mutations in EGFR. However, both resistance through a secondary T790M mutation at the gatekeeper residue and dose-limiting toxicities from wild-type (WT) EGFR inhibition ultimately limit the full potential of these therapies to control mutant EGFR-driven tumors and new therapies are urgently needed. Herein, we describe our approach toward the discovery of 47 (EGF816, nazartinib), a novel, covalent mutant-selective EGFR inhibitor with equipotent activity on both oncogenic and T790M-resistant EGFR mutations. Through molecular docking studies we converted a mutant-selective high-throughput screening hit (7) into a number of targeted covalent EGFR inhibitors with equipotent activity across mutants EGFR and good WT-EGFR selectivity. We used an abbreviated in vivo efficacy study for prioritizing compounds with good tolerability and efficacy that ultimately led to the selection of 47 as the clinical candidate.

Discovery of 1H-pyrazolo[3,4-b]pyridines as potent dual orexin receptor antagonists (DORAs).

Compound rac-1 was identified by high throughput screening. Here we report SAR studies and MedChem optimization towards the highly potent dual orexin receptor antagonists (S)-2 and (S)-3. Furthermore, strategies to overcome the suboptimal physicochemical properties are highlighted and the pharmacokinetic profiles of representative compounds is presented.

X-ray structure of PTP1B in complex with a new PTP1B inhibitor.

Protein tyrosine phosphatase 1B (PTP1B) is a prototype non receptor cytoplasmic PTPase enzyme that has been implicated in regulation of insulin and leptin signaling pathways. Studies on PTP1B knockout mice and PTP1B antisense treated mice suggested that inhibition of PTP1B would be an effective strategy for the treatment of type II diabetes and obesity. Here we report the X-ray structure of PTP1B in complex with compound IN1834-146C (PDB ID 4I8N). The crystals belong to P3121 space group with cell dimensions (a = b = 87.89 Å, c = 103.68 Å) diffracted to 2.5 Å. The crystal structure contained one molecule of protein in the asymmetric unit and was solved by molecular replacement method. The compound engages both catalytic site and allosteric sites of PTP1B protein. We described the molecular interaction of the compound with the active site residues of PTP1B in this crystal structure report.

Identification of a novel series of orexin receptor antagonists with a distinct effect on sleep architecture for the treatment of insomnia.

Dual orexin receptor (OXR) antagonists (DORAs) such as almorexant, 1 (SB-649868), or suvorexant have shown promise for the treatment of insomnias and sleep disorders in several recent clinical trials in volunteers and primary insomnia patients. The relative contribution of antagonism of OX1R and OX2R for sleep induction is still a matter of debate. We therefore initiated a drug discovery project with the aim of creating both OX2R selective antagonists and DORAs. Here we report that the OX2R selective antagonist 26 induced sleep in mice primarily by increasing NREM sleep, whereas the DORA suvorexant induced sleep largely by increasing REM sleep. Thus, OX2R selective antagonists may also be beneficial for the treatment of insomnia.

Design and synthesis of 2-substituted benzoxazoles as novel PTP1B inhibitors.

A series of benzoxazole compounds containing oxamic acid were synthesized and screened for the PTP1B inhibition. Compound 31d showed best biochemical potency (Ki) of 6.7 µM. Structure-activity relationship were explained with the help of molecular modeling approach.