Unlabelled: Medulloblastoma is one of the most common malignant brain tumors of children, and 30% of medulloblastomas are driven by gain-of-function genetic lesions in the Sonic Hedgehog (SHH) signaling pathway. EYA1, a haloacid dehalogenase phosphatase and transcription factor, is critical for tumorigenesis and proliferation of SHH medulloblastoma (SHH-MB). Benzarone and benzbromarone have been identified as allosteric inhibitors of EYA proteins.
View Article and Find Full Text PDFEpidermal growth factor receptor (EGFR) therapy using small-molecule tyrosine kinase inhibitors (TKIs) is initially efficacious in patients with EGFR-mutant lung cancer, although drug resistance eventually develops. Allosteric EGFR inhibitors, which bind to a different EGFR site than existing ATP-competitive EGFR TKIs, have been developed as a strategy to overcome therapy-resistant EGFR mutations. Here we identify and characterize JBJ-09-063, a mutant-selective allosteric EGFR inhibitor that is effective across EGFR TKI-sensitive and resistant models, including those with EGFR T790M and C797S mutations.
View Article and Find Full Text PDFThe C797S mutation confers resistance to covalent EGFR inhibitors used in the treatment of lung tumors with the activating L858R mutation. Isoindolinones such as JBJ-4-125-02 bind in an allosteric pocket and are active against this mutation, with high selectivity over wild-type EGFR. The most potent examples we developed from that series have a potential chemical instability risk from the combination of the amide and phenol groups.
View Article and Find Full Text PDFLate-stage dry age-related macular degeneration (AMD) or geographic atrophy (GA) is an irreversible blinding condition characterized by degeneration of retinal pigment epithelium (RPE) and the associated photoreceptors. Clinical and genetic evidence supports a role for dysfunctional lipid processing and accumulation of harmful oxidized lipids in the pathogenesis of GA. Using an oxidized low-density lipoprotein (ox-LDL)-induced RPE death assay, we screened and identified sterically-hindered phenol compounds with potent protective activities for RPE.
View Article and Find Full Text PDFThe protein kinase TNK2 (ACK1) is an emerging drug target for a variety of indications, in particular for cancer where it plays a key role transmitting cell survival, growth and proliferative signals via modification of multiple downstream effectors by unique tyrosine phosphorylation events. Scaffold morphing based on our previous TNK2 inhibitor XMD8-87 identified urea 17 from which we developed the potent and selective compound 32. A co-crystal structure was obtained showing 32 interacting primarily with the main chain atoms of an alanine residue of the hinge region.
View Article and Find Full Text PDFThe SAR of a series of benzopyrimidodiazepinone inhibitors of TNK2 was developed, starting from the potent and selective compound XMD8-87. A diverse set of anilines was introduced in an effort to improve the in vivo PK profile and minimize the risk of quinone diimine formation.
View Article and Find Full Text PDFKRAS is the most frequently mutated oncogene found in pancreatic, colorectal, and lung cancers. Although it has been challenging to identify targeted therapies for cancers harboring KRAS mutations, KRAS can be targeted by small-molecule inhibitors that form covalent bonds with cysteine 12 (C12). Here, we designed a library of C12-directed covalent degrader molecules (PROTACs) and subjected them to a rigorous evaluation process to rapidly identify a lead compound.
View Article and Find Full Text PDFAllosteric kinase inhibitors represent a promising new therapeutic strategy for targeting kinases harboring oncogenic driver mutations in cancers. Here, we report the discovery, optimization, and structural characterization of allosteric mutant-selective EGFR inhibitors comprising a 5,10-dihydro-11-dibenzo[,][1,4]diazepin-11-one scaffold. Our structure-based medicinal chemistry effort yielded an inhibitor () of the EGFR(L858R/T790M) and EGFR(L858R/T790M/C797S) mutants with an IC of ∼10 nM and high selectivity, as assessed by kinome profiling.
View Article and Find Full Text PDFAllosteric kinase inhibitors offer a potentially complementary therapeutic strategy to ATP-competitive kinase inhibitors due to their distinct sites of target binding. In this study, we identify and study a mutant-selective EGFR allosteric inhibitor, JBJ-04-125-02, which as a single agent can inhibit cell proliferation and EGFR signaling and . However, increased EGFR dimer formation limits treatment efficacy and leads to drug resistance.
View Article and Find Full Text PDFJanus kinases (JAKs) have been demonstrated to be critical in cytokine signaling and have thus been implicated in both cancer and inflammatory diseases. The JAK family consists of four highly homologous members: JAK1-3 and TYK2. The development of small-molecule inhibitors that are selective for a specific family member would represent highly desirable tools for deconvoluting the intricacies of JAK family biology.
View Article and Find Full Text PDFTargeted covalent small molecules have shown promise for cancers driven by KRAS G12C. Allosteric compounds that access an inducible pocket formed by movement of a dynamic structural element in KRAS, switch II, have been reported, but these compounds require further optimization to enable their advancement into clinical development. We demonstrate that covalent quinazoline-based switch II pocket (SIIP) compounds effectively suppress GTP loading of KRAS G12C, MAPK phosphorylation, and the growth of cancer cells harboring G12C.
View Article and Find Full Text PDFStructural modifications of the left-hand side of compound 1 were identified which retained or improved potent binding to Bcl-2 and Bcl-xL in in vitro biochemical assays and had strong activity in an RS4;11 apoptotic cellular assay. For example, sulfoxide diastereomer 13 maintained good binding affinity and comparable cellular potency to 1 while improving aqueous solubility. The corresponding diastereomer (14) was significantly less potent in the cell, and docking studies suggest that this is due to a stereochemical preference for the RS versus SS sulfoxide.
View Article and Find Full Text PDFThe potent and selective 3-amido-4-anilinoquinoline CSF-1R inhibitor AZ683 suffered from cardiovascular liabilities, which were linked to the off-target activities of the compound and ion channel activity in particular. Less basic and less lipophilic examples from both the quinoline and cinnoline series demonstrated cleaner secondary pharmacology profiles. Cinnoline 31 retained the required potency and oral PK profile, and was progressed through the safety screening cascade to be nominated into development as AZD7507.
View Article and Find Full Text PDFCheckpoint kinases CHK1 and CHK2 are activated in response to DNA damage that results in cell cycle arrest, allowing sufficient time for DNA repair. Agents that lead to abrogation of such checkpoints have potential to increase the efficacy of such compounds as chemo- and radiotherapies. Thiophenecarboxamide ureas (TCUs) were identified as inhibitors of CHK1 by high throughput screening.
View Article and Find Full Text PDF3-Amido-4-anilinocinnolines have been identified as potent and highly selective inhibitors of CSF-1R. The synthesis and SAR of these compounds is reported, along with some physical property, pharmacokinetic and kinase selectivity data.
View Article and Find Full Text PDFThe optimization of compounds from the 3-amido-4-anilinoquinolines series of CSF-1R kinase inhibitors is described. The series has excellent activity and kinase selectivity. Excellent physical properties and rodent PK profiles were achieved through the introduction of cyclic amines at the quinoline 6-position.
View Article and Find Full Text PDF3-amido-4-anilinoquinolines are potent and highly selective inhibitors of CSF-1R. Their synthesis and SAR is reported, along with initial efforts to optimize the physical properties and PK through modifications at the quinoline 6- and 7-positions.
View Article and Find Full Text PDFCheckpoint kinase-1 (Chk1, CHEK1) is a Ser/Thr protein kinase that mediates the cellular response to DNA-damage. A novel class of 2-ureido thiophene carboxamide urea (TCU) Chk1 inhibitors is described. Inhibitors in this chemotype were optimized for cellular potency and selectivity over Cdk1.
View Article and Find Full Text PDFThe enantiomers of 2-[2-(dimethylamino)ethyl]-3,4-dihydro-4-methylpyrido[3,2-f]-1,4- oxazapine-5(2H)-thione (rocastine) and two of its more potent analogues were prepared with an enantiomeric purity of greater than 99.9%. The antihistaminic activity of these compounds was assessed by their ability to block histamine-induced lethality in guinea pigs and to inhibit [3H]mepyramine binding to guinea pig cortex.
View Article and Find Full Text PDFA series of novel benzo- and pyrido-1,4-oxazepinones and -thiones which represents a new structural class of compounds possessing H1 antihistaminic activity was synthesized, and the SARs were evaluated. The antihistaminic activity was determined by blockade of histamine-induced lethality in guinea pigs. The sedative potential was determined by comparison of the EEG profiles of the compounds with those of known sedating and nonsedating antihistamines.
View Article and Find Full Text PDFBiochem Biophys Res Commun
May 1984
A cyclic pseudohexapeptide analog of somatostatin, cyclo(Pro psi[ CH2S ]Phe-D-Trp-Lys-Thr-Phe) was synthesized by solid phase methods and diphenylphosphoryl azide ring closure. The resulting crystalline compound possessed 23% of the growth hormone inhibitory activity of the parent tetradecapeptide and approximately 6% of the activity of the all-amide cyclic hexapeptide analog in spite of the absence of one of two postulated intramolecular hydrogen bonds.
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