RESUMO
PRMT5, a type 2 arginine methyltransferase, has a critical role in regulating cell growth and survival in cancer. With the aim of developing MTA-cooperative PRMT5 inhibitors suitable for MTAP-deficient cancers, herein we report our efforts to develop novel "MTA-cooperative" compounds identified through a high-throughput biochemical screening approach. Optimization of hits was achieved through structure-based design with a focus on improvement of oral drug-like properties. Bioisosteric replacement of the original thiazole guanidine headgroup, spirocyclization of the isoindolinone amide scaffold to both configurationally and conformationally lock the bioactive form, and fine-tuning of the potency, MTA cooperativity, and DMPK properties through specific substitutions of the azaindole headgroup were conducted. We have identified an orally available in vivo lead compound, 28 ("AZ-PRMT5i-1"), which shows sub-10 nM PRMT5 cell potency, >50-fold MTA cooperativity, suitable DMPK properties for oral dosing, and significant PRMT5-driven in vivo efficacy in several MTAP-deficient preclinical cancer models.
RESUMO
In vitro metabolism studies of the spleen tyrosine kinase inhibitors AZ-A and AZ-B identified four unusual metabolites. M1 (mass-to-charge ratio 411) was formed by both molecules and was common to several analogs (AZ-C to AZ-H) sharing the same core structure, appearing to derive from the complete loss of a pendent 3,4-diaminotetrahydropyran ring and pyrazole ring cleavage resulting in a nonobvious metabolite. M2-M4 were formed by AZ-A and a subset of the other compounds only and apparently resulted from a sequential loss of H2 from parent. Initial attempts to isolate M3 for identification were unsuccessful due to sample degradation, and it was subsequently found that M2 and M3 underwent sequential chemical degradation steps to M4. M4 was successfully isolated and shown by mass spectrometry and NMR spectroscopy to be a tricyclic species incorporating the pyrazole and the 3,4-diaminotetrahydropyran groups. We propose that this arises from an intramolecular reaction between the primary amine on the tetrahydropyran and a putative epoxide intermediate on the adjacent pyrazole ring, evidence for which was generated in a ß-mercaptoethanol-trapping experiment. The loss of the tetrahydropyran moiety observed in M1 was found to be enhanced in an analog that was unable to undergo the intramolecular reaction step, leading us to propose two possible reaction pathways originating from the reactive intermediate. Ultimately, we conclude that the apparently complex and unusual metabolism of this series of compounds likely resulted from a single metabolic activation step forming an epoxide intermediate, which subsequently underwent intramolecular rearrangement and/or chemical degradation to form the final observed products. SIGNIFICANCE STATEMENT: The current work provides an unusual biotransformation example showing the potential for intramolecular reactions and chemical degradation to give the appearance of complex metabolism arising from a single primary route of metabolism.
Assuntos
Biotransformação , Proteínas Tirosina Quinases , Quinase Syk , Quinase Syk/metabolismo , Quinase Syk/antagonistas & inibidores , Humanos , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Inibidores de Proteínas Quinases/metabolismo , Microssomos Hepáticos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Pirazóis/metabolismoRESUMO
The inhibition of ataxia-telangiectasia mutated (ATM) has been shown to chemo- and radio-sensitize human glioma cells in vitro and therefore might provide an exciting new paradigm in the treatment of glioblastoma multiforme (GBM). The effective treatment of GBM will likely require a compound with the potential to efficiently cross the blood-brain barrier (BBB). Starting from clinical candidate AZD0156, 4, we investigated the imidazoquinolin-2-one scaffold with the goal of improving likely CNS exposure in humans. Strategies aimed at reducing hydrogen bonding, basicity, and flexibility of the molecule were explored alongside modulating lipophilicity. These studies identified compound 24 (AZD1390) as an exceptionally potent and selective inhibitor of ATM with a good preclinical pharmacokinetic profile. 24 showed an absence of human transporter efflux in MDCKII-MDR1-BCRP studies (efflux ratio <2), significant BBB penetrance in nonhuman primate PET studies (Kp,uu 0.33) and was deemed suitable for development as a clinical candidate to explore the radiosensitizing effects of ATM in intracranial malignancies.
Assuntos
Ataxia Telangiectasia , Glioblastoma , Piridinas , Quinolonas , Animais , Humanos , Barreira Hematoencefálica/metabolismo , Ataxia Telangiectasia/tratamento farmacológico , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Neoplasias , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Glioblastoma/tratamento farmacológicoRESUMO
Spleen tyrosine kinase (SYK) is a non-receptor cytoplasmic kinase. Due to its pivotal role in B cell receptor and Fc-receptor signalling, inhibition of SYK has been a target of interest in a variety of diseases. Herein, we report the use of structure-based drug design to discover a series of potent macrocyclic inhibitors of SYK, with excellent kinome selectivity and in vitro metabolic stability. We were able to remove hERG inhibition through the optimization of physical properties, and utilized a pro-drug strategy to address permeability challenges.
Assuntos
Proteínas Tirosina Quinases , Transdução de Sinais , Quinase Syk , Inibidores de Proteínas Quinases/farmacologiaRESUMO
Herein, we report the optimization of a meta-substituted series of selective estrogen receptor degrader (SERD) antagonists for the treatment of ER+ breast cancer. Structure-based design together with the use of modeling and NMR to favor the bioactive conformation led to a highly potent series of basic SERDs with promising physicochemical properties. Issues with hERG activity resulted in a strategy of zwitterion formation and ultimately in the identification of 38. This compound was shown to be a highly potent SERD capable of effectively degrading ERα in both MCF-7 and CAMA-1 cell lines. The low lipophilicity and zwitterionic nature led to a SERD with a clean secondary pharmacology profile and no hERG activity. Favorable physicochemical properties resulted in good oral bioavailability in preclinical species and potent in vivo activity in a mouse xenograft model.
Assuntos
Neoplasias da Mama , Receptores de Estrogênio , Camundongos , Humanos , Animais , Feminino , Receptores de Estrogênio/metabolismo , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Antagonistas de Estrogênios/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Receptor alfa de Estrogênio/metabolismo , Linhagem CelularRESUMO
INTRODUCTION: The estrogen receptor (ER) is a clinically validated oncology target with a pivotal role in hormonally driven breast cancer, the most prevalent form of female cancer. Current treatments that directly modulate ER include antagonists (SERMs), such as tamoxifen, and degraders (SERDs), such as fulvestrant which is administered by intramuscular injection. AREAS COVERED: This review covers patent applications that claim estrogen receptor degraders (SERDs) and covalent antagonists (SERCAs) between the period January 2015 to June 2021. A total of 114 patent applications from 23 different applicants are evaluated with stratification into acidic SERDs, basic SERDs, and SERCAs. EXPERT OPINION: The clinical success of fulvestrant in the treatment of ER+ breast cancer has spurred research over the last decade into the discovery and development of novel SERDs, with a particular focus on the discovery of orally bioavailable drugs. This has resulted in a diverse range of candidates entering clinical trials. Although some have faltered in development, a cohort of oral SERDs has generated encouraging efficacy and safety data that has allowed advancement into late stage clinical trials. Data from these trials is eagerly awaited, with these molecules having the potential to offer significant benefits in the treatment of ER+ breast cancer.
Assuntos
Neoplasias da Mama , Receptores de Estrogênio , Neoplasias da Mama/tratamento farmacológico , Antagonistas de Estrogênios/uso terapêutico , Receptor alfa de Estrogênio , Feminino , Humanos , Patentes como Assunto , Receptores de Estrogênio/uso terapêutico , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Moduladores Seletivos de Receptor Estrogênico/uso terapêuticoRESUMO
Cyclin-dependent-kinases (CDKs) are members of the serine/threonine kinase family and are highly regulated by cyclins, a family of regulatory subunits that bind to CDKs. CDK9 represents one of the most studied examples of these transcriptional CDKs. CDK9 forms a heterodimeric complex with its regulatory subunit cyclins T1, T2 and K to form the positive transcription elongation factor b (P-TEFb). This complex regulates transcription via the phosphorylation of RNA polymerase II (RNAPolII) on Ser-2, facilitating promoter clearance and transcription elongation and thus remains an attractive therapeutic target. Herein, we have utilized classical affinity purification chemical proteomics, kinobeads assay, compressed CEllular Thermal Shift Assay (CETSA)-MS and Limited Proteolysis (LiP) to study the selectivity, target engagement and downstream mechanistic insights of a CDK9 tool compound. The above experiments highlight the value of quantitative mass spectrometry approaches to drug discovery, specifically proteome wide target identification and selectivity profiling. The approaches utilized in this study unanimously indicated that the CDK family of kinases are the main target of the compound of interest, with CDK9, showing the highest target affinity with remarkable consistency across approaches. We aim to provide guidance to the scientific community on the available chemical biology/proteomic tools to study advanced lead molecules and to highlight pros and cons of each technology while describing our findings in the context of the CDKs biology.
Assuntos
Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Proteômica , Linhagem Celular Tumoral , Fracionamento Químico , Quinase 9 Dependente de Ciclina/genética , Quinase 9 Dependente de Ciclina/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Espectrometria de MassasRESUMO
Optimization of a series of azabenzimidazoles identified from screening hit 2 and the information gained from a co-crystal structure of the azabenzimidazole-based lead 6 bound to CDK9 led to the discovery of azaindoles as highly potent and selective CDK9 inhibitors. With the goal of discovering a highly selective and potent CDK9 inhibitor administrated intravenously that would enable transient target engagement of CDK9 for the treatment of hematological malignancies, further optimization focusing on physicochemical and pharmacokinetic properties led to azaindoles 38 and 39. These compounds are highly potent and selective CDK9 inhibitors having short half-lives in rodents, suitable physical properties for intravenous administration, and the potential to achieve profound but transient inhibition of CDK9 in vivo.
Assuntos
Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Descoberta de Drogas , Indóis/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Quinase 9 Dependente de Ciclina/metabolismo , Relação Dose-Resposta a Droga , Humanos , Indóis/síntese química , Indóis/química , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Relação Estrutura-AtividadeRESUMO
A CDK9 inhibitor having short target engagement would enable a reduction of Mcl-1 activity, resulting in apoptosis in cancer cells dependent on Mcl-1 for survival. We report the optimization of a series of amidopyridines (from compound 2), focusing on properties suitable for achieving short target engagement after intravenous administration. By increasing potency and human metabolic clearance, we identified compound 24, a potent and selective CDK9 inhibitor with suitable predicted human pharmacokinetic properties to deliver transient inhibition of CDK9. Furthermore, the solubility of 24 was considered adequate to allow i.v. formulation at the anticipated effective dose. Short-term treatment with compound 24 led to a rapid dose- and time-dependent decrease of pSer2-RNAP2 and Mcl-1, resulting in cell apoptosis in multiple hematological cancer cell lines. Intermittent dosing of compound 24 demonstrated efficacy in xenograft models derived from multiple hematological tumors. Compound 24 is currently in clinical trials for the treatment of hematological malignancies.
Assuntos
Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Piridinas/química , Animais , Apoptose/efeitos dos fármacos , Sítios de Ligação , Linhagem Celular Tumoral , Quinase 9 Dependente de Ciclina/metabolismo , Cães , Avaliação Pré-Clínica de Medicamentos , Meia-Vida , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/patologia , Humanos , Camundongos , Simulação de Acoplamento Molecular , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/metabolismo , Piridinas/farmacologia , Piridinas/uso terapêutico , Ratos , Solubilidade , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Herein we describe our efforts using a late stage functionalization together with more traditional synthetic approaches to generate fluorinated analogues of the clinical candidate AZD9833. The effects of the addition of fluorine on the lipophilicity, permeability, and metabolism are discussed. Many of these changes were tolerated in terms of pharmacology and resulted in high quality molecules which reached advanced stages of profiling in the testing cascade.
RESUMO
Herein we report the optimization of a series of tricyclic indazoles as selective estrogen receptor degraders (SERD) and antagonists for the treatment of ER+ breast cancer. Structure based design together with systematic investigation of each region of the molecular architecture led to the identification of N-[1-(3-fluoropropyl)azetidin-3-yl]-6-[(6S,8R)-8-methyl-7-(2,2,2-trifluoroethyl)-6,7,8,9-tetrahydro-3H-pyrazolo[4,3-f]isoquinolin-6-yl]pyridin-3-amine (28). This compound was demonstrated to be a highly potent SERD that showed a pharmacological profile comparable to fulvestrant in its ability to degrade ERα in both MCF-7 and CAMA-1 cell lines. A stringent control of lipophilicity ensured that 28 had favorable physicochemical and preclinical pharmacokinetic properties for oral administration. This, combined with demonstration of potent in vivo activity in mouse xenograft models, resulted in progression of this compound, also known as AZD9833, into clinical trials.
Assuntos
Antineoplásicos/administração & dosagem , Moduladores Seletivos de Receptor Estrogênico/administração & dosagem , Administração Oral , Antineoplásicos/química , Antineoplásicos/farmacocinética , Disponibilidade Biológica , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Ciclização , Descoberta de Drogas , Feminino , Humanos , Lipídeos/química , Estrutura Molecular , Moduladores Seletivos de Receptor Estrogênico/química , Moduladores Seletivos de Receptor Estrogênico/farmacocinética , Relação Estrutura-AtividadeRESUMO
Hybridisation of amino-pyrimidine based SYK inhibitors (e.g. 1a) with previously reported diamine-based SYK inhibitors (e.g. TAK-659) led to the identification and optimisation of a novel pyrimidine-based series of potent and selective SYK inhibitors, where the original aminomethylene group was replaced by a 3,4-diaminotetrahydropyran group. The initial compound 5 achieved excellent SYK potency. However, it suffered from poor permeability and modest kinase selectivity. Further modifications of the 3,4-diaminotetrahydropyran group were identified and the interactions of those groups with Asp512 were characterised by protein X-ray crystallography. Further optimisation of this series saw mixed results where permeability and kinase selectivity were increased and oral bioavailability was achieved in the series, but at the expense of potent hERG inhibition.
Assuntos
Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Quinase Syk/antagonistas & inibidores , Animais , Cães , Relação Dose-Resposta a Droga , Humanos , Microssomos Hepáticos/química , Microssomos Hepáticos/metabolismo , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Pirazóis/síntese química , Pirazóis/química , Pirimidinas/síntese química , Pirimidinas/química , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Quinase Syk/metabolismoRESUMO
Spleen Tyrosine Kinase (SYK) is a well-studied enzyme with therapeutic applications in oncology and autoimmune diseases. We identified an azabenzimidazole (ABI) series of SYK inhibitors by mining activity data of 86,000 compounds from legacy biochemical assays with SYK and other homologous kinases as target enzymes. A structure-based design and hybridization approach was then used to improve the potency and kinase selectivity of the hits. Lead compound 23 from this novel ABI series has a SYK IC50 = 0.21 nM in a biochemical assay and inhibits growth of SUDHL-4 cells at a GI50 = 210 nM.
Assuntos
Doenças Autoimunes/tratamento farmacológico , Compostos Aza/química , Benzimidazóis/química , Inibidores de Proteínas Quinases/química , Quinase Syk/antagonistas & inibidores , Sequência de Aminoácidos , Compostos Aza/farmacologia , Benzimidazóis/farmacologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Humanos , Concentração Inibidora 50 , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Inibidores de Proteínas Quinases/farmacologia , Relação Estrutura-Atividade , Especificidade por SubstratoRESUMO
Spleen tyrosine kinase (SYK) is a non-receptor cytosolic kinase. Due to its pivotal role in B cell receptor and Fc-receptor signaling, inhibition of SYK has been targeted in a variety of disease areas. Herein, we report the optimization of a series of potent and selective SYK inhibitors, focusing on improving metabolic stability, pharmacokinetics and hERG inhibition. As a result, we identified 30, which exhibited no hERG activity but unfortunately was poorly absorbed in rats and mice. We also identified a SYK chemical probe, 17, which exhibits excellent potency at SYK, and an adequate rodent PK profile to support in vivo efficacy/PD studies.
Assuntos
Indazóis/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Quinase Syk/antagonistas & inibidores , Animais , Sítios de Ligação , Células CACO-2 , Cristalografia por Raios X , Canal de Potássio ERG1/antagonistas & inibidores , Humanos , Indazóis/síntese química , Indazóis/metabolismo , Indazóis/farmacocinética , Camundongos , Microssomos Hepáticos/metabolismo , Estrutura Molecular , Ligação Proteica , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacocinética , Ratos Wistar , Relação Estrutura-Atividade , Quinase Syk/química , Quinase Syk/metabolismoRESUMO
AZD0156 is a potent and selective, bioavailable inhibitor of ataxia-telangiectasia mutated (ATM) protein, a signaling kinase involved in the DNA damage response. We present preclinical data demonstrating abrogation of irradiation-induced ATM signaling by low doses of AZD0156, as measured by phosphorylation of ATM substrates. AZD0156 is a strong radiosensitizer in vitro, and using a lung xenograft model, we show that systemic delivery of AZD0156 enhances the tumor growth inhibitory effects of radiation treatment in vivo Because ATM deficiency contributes to PARP inhibitor sensitivity, preclinically, we evaluated the effect of combining AZD0156 with the PARP inhibitor olaparib. Using ATM isogenic FaDu cells, we demonstrate that AZD0156 impedes the repair of olaparib-induced DNA damage, resulting in elevated DNA double-strand break signaling, cell-cycle arrest, and apoptosis. Preclinically, AZD0156 potentiated the effects of olaparib across a panel of lung, gastric, and breast cancer cell lines in vitro, and improved the efficacy of olaparib in two patient-derived triple-negative breast cancer xenograft models. AZD0156 is currently being evaluated in phase I studies (NCT02588105).
Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/uso terapêutico , Ftalazinas/uso terapêutico , Piperazinas/uso terapêutico , Piridinas/uso terapêutico , Quinolinas/uso terapêutico , Radiossensibilizantes/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/radioterapia , Animais , Proteínas Mutadas de Ataxia Telangiectasia/farmacologia , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Camundongos Nus , Ftalazinas/farmacologia , Piperazinas/farmacologia , Piridinas/farmacologia , Quinolinas/farmacologia , Radiossensibilizantes/farmacologia , Neoplasias de Mama Triplo Negativas/patologiaRESUMO
We report the discovery of a novel series of 3-cinnoline carboxamides as highly potent and selective ataxia telangiectasia mutated (ATM) kinase inhibitors. Optimization of this series focusing on potency and physicochemical properties (especially permeability) led to the identification of compound 21, a highly potent ATM inhibitor (ATM cell IC50 0.0028 µM) with excellent kinase selectivity and favorable physicochemical and pharmacokinetics properties. In vivo, 21 in combination with irinotecan showed tumor regression in the SW620 colorectal tumor xenograft model, superior inhibition to irinotecan alone. Compound 21 was selected for preclinical evaluation alongside AZD0156.
RESUMO
Inhibition of ataxia-telangiectasia mutated (ATM) during radiotherapy of glioblastoma multiforme (GBM) may improve tumor control by short-circuiting the response to radiation-induced DNA damage. A major impediment for clinical implementation is that current inhibitors have limited central nervous system (CNS) bioavailability; thus, the goal was to identify ATM inhibitors (ATMi) with improved CNS penetration. Drug screens and refinement of lead compounds identified AZ31 and AZ32. The compounds were then tested in vivo for efficacy and impact on tumor and healthy brain. Both AZ31 and AZ32 blocked the DNA damage response and radiosensitized GBM cells in vitro AZ32, with enhanced blood-brain barrier (BBB) penetration, was highly efficient in vivo as radiosensitizer in syngeneic and human, orthotopic mouse glioma model compared with AZ31. Furthermore, human glioma cell lines expressing mutant p53 or having checkpoint-defective mutations were particularly sensitive to ATMi radiosensitization. The mechanism for this p53 effect involves a propensity to undergo mitotic catastrophe relative to cells with wild-type p53. In vivo, apoptosis was >6-fold higher in tumor relative to healthy brain after exposure to AZ32 and low-dose radiation. AZ32 is the first ATMi with oral bioavailability shown to radiosensitize glioma and improve survival in orthotopic mouse models. These findings support the development of a clinical-grade, BBB-penetrating ATMi for the treatment of GBM. Importantly, because many GBMs have defective p53 signaling, the use of an ATMi concurrent with standard radiotherapy is expected to be cancer-specific, increase the therapeutic ratio, and maintain full therapeutic effect at lower radiation doses. Mol Cancer Ther; 17(8); 1637-47. ©2018 AACR.
Assuntos
Barreira Hematoencefálica/metabolismo , Glioma/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Radiossensibilizantes/uso terapêutico , Administração Oral , Animais , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Nus , Inibidores de Proteínas Quinases/farmacologia , Radiossensibilizantes/farmacologiaRESUMO
ATM inhibitors, such as 7, have demonstrated the antitumor potential of ATM inhibition when combined with DNA double-strand break-inducing agents in mouse xenograft models. However, the properties of 7 result in a relatively high predicted clinically efficacious dose. In an attempt to minimize attrition during clinical development, we sought to identify ATM inhibitors with a low predicted clinical dose (<50 mg) and focused on strategies to increase both ATM potency and predicted human pharmacokinetic half-life (predominantly through the increase of volume of distribution). These efforts resulted in the discovery of 64 (AZD0156), an exceptionally potent and selective inhibitor of ATM based on an imidazo[4,5- c]quinolin-2-one core. 64 has good preclinical phamacokinetics, a low predicted clinical dose, and a high maximum absorbable dose. 64 has been shown to potentiate the efficacy of the approved drugs irinotecan and olaparib in disease relevant mouse models and is currently undergoing clinical evaluation with these agents.
Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Desenho de Fármacos , Piridinas/farmacocinética , Quinolinas/farmacocinética , Quinolonas/farmacologia , Quinolonas/farmacocinética , Administração Oral , Proteínas Mutadas de Ataxia Telangiectasia/química , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Disponibilidade Biológica , Humanos , Concentração Inibidora 50 , Modelos Moleculares , Conformação Proteica , Inibidores de Proteínas Quinases , Piridinas/administração & dosagem , Piridinas/química , Quinolinas/administração & dosagem , Quinolinas/química , Quinolonas/administração & dosagem , Quinolonas/química , Relação Estrutura-Atividade , Especificidade por SubstratoRESUMO
We report the discovery of a novel aminopyrazine series of PI3Kα inhibitors, designed by hybridizing two known scaffolds of PI3K inhibitors. We describe the progress achieved from the first compounds plagued with poor general kinase selectivity to compounds showing high selectivity for PI3Kα over PI3Kß and excellent general kinase selectivity. This effort culminated with the identification of compound 5 displaying high potency and selectivity, and suitable physiochemical and pharmacokinetic properties for oral administration. In vivo, compound 5 showed good inhibition of tumour growth (86% tumour growth inhibition at 50mg/kg twice daily orally) in the MCF7 xenograft model in mice.