Discovery and Optimization of Selective Inhibitors of Large Tumor Suppressor Kinases LATS1 and 2 for In Vivo Investigation of the Hippo-YAP Pathway in Tissue Regeneration.

Large Tumor Suppressor kinases LATS1 and 2 (LATS1/2) are serine/threonine kinases and core regulators of the Hippo-YAP pathway. Inhibition of LATS1/2 promotes nuclear translocation of nonphosphorylated YAP, thereby initiating a downstream cascade promoting cell proliferation. We set out to investigate the potential of LATS inhibition as a therapeutic approach to enhance tissue regeneration and hereby report a structure-guided optimization of screening hit for potency, binding efficiency, and physicochemical properties, leading to a highly selective, cellularly active, and orally available tool compound (NIBR-LTSi) that demonstrated target engagement and in vivo YAP target gene activation in rodents.

JDQ443, a Structurally Novel, Pyrazole-Based, Covalent Inhibitor of KRAS for the Treatment of Solid Tumors.

Rapid emergence of tumor resistance via RAS pathway reactivation has been reported from clinical studies of covalent KRAS inhibitors. Thus, inhibitors with broad potential for combination treatment and distinct binding modes to overcome resistance mutations may prove beneficial. JDQ443 is an investigational covalent KRAS inhibitor derived from structure-based drug design followed by extensive optimization of two dissimilar prototypes.

Discovery of Umibecestat (CNP520): A Potent, Selective, and Efficacious β-Secretase (BACE1) Inhibitor for the Prevention of Alzheimer's Disease.

After identification of lead compound , 5-amino-1,4-oxazine BACE1 inhibitors were optimized in order to improve potency, brain penetration, and metabolic stability. Insertion of a methyl and a trifluoromethyl group at the 6-position of the 5-amino-1,4-oxazine led to (), an inhibitor with a p of 7.1, a very low P-glycoprotein efflux ratio, and excellent pharmacological profile, enabling high central nervous system penetration and exposure.

Synthesis of the Potent, Selective, and Efficacious β-Secretase (BACE1) Inhibitor NB-360.

Starting from lead compound , the 1,4-oxazine headgroup was optimized to improve potency and brain penetration. Focusing at the 6-position of the 5-amino-1,4-oxazine, the insertion of a Me and a CF group delivered an excellent pharmacological profile with a p of 7.1 and a very low P-gp efflux ratio enabling high central nervous system (CNS) penetration and exposure.

Discovery and Structural Characterization of ATP-Site Ligands for the Wild-Type and V617F Mutant JAK2 Pseudokinase Domain.

The oncogenic V617F mutation lies in the pseudokinase domain of JAK2, marking it as a potential target for development of compounds that might inhibit the pathogenic activity of the mutant protein. We used differential scanning fluorimetry to identify compounds that bind the JAK2 pseudokinase domain. Crystal structures of five candidate compounds with the wild-type domain reveal their modes of binding.

The β-secretase (BACE) inhibitor NB-360 in preclinical models: From amyloid-β reduction to downstream disease-relevant effects.

Inhibition of β-secretase 1 (BACE-1; also known as β-site amyloid precursor protein-cleaving enzyme-1) is a current approach to fight the amyloid-β (Aβ) deposition in the brains of patients with Alzheimer's disease, and a number of BACE-1 inhibitors are being tested in clinical trials. The BACE-1 inhibitor NB-360, although not a clinical compound, turned out to be a valuable pharmacological tool to investigate the effects of BACE-1 inhibition on the deposition of different Aβ species in amyloid precursor protein (APP) transgenic mice. Furthermore, chronic animal studies with NB-360 revealed relationships between BACE-1 inhibition, Aβ deposition, and Aβ-related downstream effects on neuroinflammation, neuronal function, and markers of neurodegeneration.

The BACE-1 inhibitor CNP520 for prevention trials in Alzheimer's disease.

The beta-site amyloid precursor protein cleaving enzyme-1 (BACE-1) initiates the generation of amyloid-β (Aβ), and the amyloid cascade leading to amyloid plaque deposition, neurodegeneration, and dementia in Alzheimer's disease (AD). Clinical failures of anti-Aβ therapies in dementia stages suggest that treatment has to start in the early, asymptomatic disease states. The BACE-1 inhibitor CNP520 has a selectivity, pharmacodynamics, and distribution profile suitable for AD prevention studies.

Discovery of amino-1,4-oxazines as potent BACE-1 inhibitors.

New amino-1,4-oxazine derived BACE-1 inhibitors were explored and various synthetic routes developed. The binding mode of the inhibitors was elucidated by co-crystallization of 4 with BACE-1 and X-ray analysis. Subsequent optimization led to inhibitors with low double digit nanomolar activity in a biochemical and single digit nanomolar potency in a cellular assays.

Discovery of Potent, Selective, and Structurally Novel Dot1L Inhibitors by a Fragment Linking Approach.

Misdirected catalytic activity of histone methyltransferase Dot1L is believed to be causative for a subset of highly aggressive acute leukemias. Targeting the catalytic domain of Dot1L represents a potential therapeutic approach for these leukemias. In the context of a comprehensive Dot1L hit finding strategy, a knowledge-based virtual screen of the Dot1L SAM binding pocket led to the discovery of , a non-nucleoside fragment mimicking key interactions of SAM bound to Dot1L.

Discovery of Novel Dot1L Inhibitors through a Structure-Based Fragmentation Approach.

Oncogenic MLL fusion proteins aberrantly recruit Dot1L, a histone methyltransferase, to ectopic loci, leading to local hypermethylation of H3K79 and misexpression of HoxA genes driving MLL-rearranged leukemias. Inhibition of the methyltransferase activity of Dot1L in this setting is predicted to reverse aberrant H3K79 methylation, leading to repression of leukemogenic genes and tumor growth inhibition. In the context of our Dot1L drug discovery program, high-throughput screening led to the identification of 2, a weak Dot1L inhibitor with an unprecedented, induced pocket binding mode.

Pharmacological BACE1 and BACE2 inhibition induces hair depigmentation by inhibiting PMEL17 processing in mice.

Melanocytes of the hair follicle produce melanin and are essential in determining the differences in hair color. Pigment cell-specific MELanocyte Protein (PMEL17) plays a crucial role in melanogenesis. One of the critical steps is the amyloid-like functional oligomerization of PMEL17.

A novel BACE inhibitor NB-360 shows a superior pharmacological profile and robust reduction of amyloid-β and neuroinflammation in APP transgenic mice.

Background: Alzheimer's disease (AD) is the most common form of dementia, the number of affected individuals is rising, with significant impacts for healthcare systems. Current symptomatic treatments delay, but do not halt, disease progression. Genetic evidence points to aggregation and deposition of amyloid-β (Aβ) in the brain being causal for the neurodegeneration and dementia typical of AD.

Discovery of cyclic sulfoxide hydroxyethylamines as potent and selective β-site APP-cleaving enzyme 1 (BACE1) inhibitors: structure based design and in vivo reduction of amyloid β-peptides.

Previous structure based optimization in our laboratories led to the identification of a novel, high-affinity cyclic sulfone hydroxyethylamine-derived inhibitor such as 1 that lowers CNS-derived Aβ following oral administration to transgenic APP51/16 mice. Herein we report SAR development in the S3 and S2' subsites of BACE1 for cyclic sulfoxide hydroxyethyl amine inhibitors, the synthetic approaches employed in this effort, and in vivo data for optimized compound such as 11d.

Discovery of cyclic sulfone hydroxyethylamines as potent and selective β-site APP-cleaving enzyme 1 (BACE1) inhibitors: structure-based design and in vivo reduction of amyloid β-peptides.

Structure-based design of a series of cyclic hydroxyethylamine BACE1 inhibitors allowed the rational incorporation of prime- and nonprime-side fragments to a central core template without any amide functionality. The core scaffold selection and the structure-activity relationship development were supported by molecular modeling studies and by X-ray analysis of BACE1 complexes with various ligands to expedite the optimization of the series. The direct extension from P1-aryl- and heteroaryl moieties into the S3 binding pocket allowed the enhancement of potency and selectivity over cathepsin D.

Macrocyclic BACE-1 inhibitors acutely reduce Abeta in brain after po application.

A series of macrocyclic peptidic BACE-1 inhibitors was designed. While potency on BACE-1 was rather high, the first set of compounds showed poor brain permeation and high efflux in the MDRI-MDCK assay. The replacement of the secondary benzylamino group with a phenylcyclopropylamino group maintained potency on BACE-1, while P-glycoprotein-mediated efflux was significantly reduced and brain permeation improved.

Macrocyclic peptidomimetic beta-secretase (BACE-1) inhibitors with activity in vivo.

The macrocyclic peptidic BACE-1 inhibitors 2a-c show moderate enzymatic and cellular activity. By exchange of the hydroxyethylene- to ethanolamine-transition state mimetic the peptidic character was reduced, providing the highly potent and selective inhibitor 3. Variation of the P' moiety resulted in the macrocyclic inhibitor 14.

Structure-based design and synthesis of macrocyclic peptidomimetic beta-secretase (BACE-1) inhibitors.

The hydroxyethylene octapeptide inhibitor OM99-2 served as starting point to create the tripeptide inhibitor 1 and its analogues 2a and b. An X-ray co-crystal structure of 1 with BACE-1 allowed the design and syntheses of a series of macrocyclic analogues 3a-h covalently linking the P1 and P3 side-chains. These inhibitors show improved enzymatic potency over their open-chain analogue.