RESUMO
AICARFT is a folate dependent catalytic site within the ATIC gene, part of the purine biosynthetic pathway, a pathway frequently upregulated in cancers. LSN3213128 is a potent (16 nM) anti-folate inhibitor of AICARFT and selective relative to TS, SHMT1, MTHFD1, MTHFD2 and MTHFD2L. Increases in ZMP, accompanied by activation of AMPK and cell growth inhibition, were observed with treatment of LY3213128. These effects on ZMP and proliferation were dependent on folate levels. In human breast MDA-MB-231met2 and lung NCI-H460 cell lines, growth inhibition was rescued by hypoxanthine, but not in the A9 murine cell line which is deficient in purine salvage. In athymic nude mice, LSN3213128 robustly elevates ZMP in MDA-MB-231met2, NCI-H460 and A9 tumors in a time and dose dependent manner. Significant tumor growth inhibition in human breast MDA-MB231met2 and lung NCI-H460 xenografts and in the syngeneic A9 tumor model were observed with oral administration of LSN3213128. Strikingly, AMPK appeared activated within the tumors and did not change even at high levels of intratumoral ZMP after weeks of dosing. These results support the evaluation of LSN3213128 as an antineoplastic agent.
Assuntos
Aminoimidazol Carboxamida/análogos & derivados , Antineoplásicos , Inibidores Enzimáticos/farmacologia , Hidroximetil e Formil Transferases/antagonistas & inibidores , Neoplasias Pulmonares , Complexos Multienzimáticos/antagonistas & inibidores , Proteínas de Neoplasias/antagonistas & inibidores , Nucleotídeo Desaminases/antagonistas & inibidores , Ribonucleotídeos , Aminoimidazol Carboxamida/farmacocinética , Aminoimidazol Carboxamida/farmacologia , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Feminino , Humanos , Hidroximetil e Formil Transferases/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus , Complexos Multienzimáticos/metabolismo , Proteínas de Neoplasias/metabolismo , Nucleotídeo Desaminases/metabolismo , Ribonucleotídeos/farmacocinética , Ribonucleotídeos/farmacologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
A hallmark of cancer is unbridled proliferation that can result in increased demand for de novo synthesis of purine and pyrimidine bases required for DNA and RNA biosynthesis. These synthetic pathways are frequently upregulated in cancer and involve various folate-dependent enzymes. Antifolates have a proven record as clinically used oncolytic agents. Our recent research efforts have produced LSN 3213128 (compound 28a), a novel, selective, nonclassical, orally bioavailable antifolate with potent and specific inhibitory activity for aminoimidazole-4-carboxamide ribonucleotide formyltransferase (AICARFT), an enzyme in the purine biosynthetic pathway. Inhibition of AICARFT with compound 28a results in dramatic elevation of 5-aminoimidazole 4-carboxamide ribonucleotide (ZMP) and growth inhibition in NCI-H460 and MDA-MB-231met2 cancer cell lines. Treatment with this inhibitor in a murine based xenograft model of triple negative breast cancer (TNBC) resulted in tumor growth inhibition.
Assuntos
Antineoplásicos/química , Antineoplásicos/uso terapêutico , Antagonistas do Ácido Fólico/química , Antagonistas do Ácido Fólico/uso terapêutico , Fosforribosilaminoimidazolcarboxamida Formiltransferase/antagonistas & inibidores , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Mama/efeitos dos fármacos , Mama/metabolismo , Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Descoberta de Drogas , Feminino , Antagonistas do Ácido Fólico/farmacocinética , Antagonistas do Ácido Fólico/farmacologia , Humanos , Masculino , Camundongos , Camundongos Nus , Modelos Moleculares , Fosforribosilaminoimidazolcarboxamida Formiltransferase/metabolismo , Sulfonamidas/química , Sulfonamidas/farmacocinética , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Tiofenos/química , Tiofenos/farmacocinética , Tiofenos/farmacologia , Tiofenos/uso terapêutico , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologiaRESUMO
In this paper, we report for the first time two enantioselective routes to 4,4-difluoropyrrolidin-3-ol, a valuable building block in medicinal chemistry. In the first route, we took advantage of the C2 symmetry of (3R,4R)-3,4-dihydroxypyrrolidine in which the desired chirality was derived from the chiral pool (l-(+)-tartaric acid). In the second route, we efficiently assembled the pyrrolidine ring in the presence of a gem-difluoro moiety to avoid using potentially hazardous deoxofluorinating reagents and subsequently introduced the chirality by a stereoselective iridium-diamine-catalyzed asymmetric transfer hydrogenation reaction.
RESUMO
Novel 2'-modified guanosine nucleosides were synthesized from inexpensive starting materials in 7-10 steps via hydroazidation or hydrocyanation reactions of the corresponding 2'-olefin. The antiviral effectiveness of the guanosine nucleosides was evaluated by converting them to the corresponding 5'-O-triphosphates (compounds 38-44) and testing their biochemical inhibitory activity against the wild-type NS5B polymerase.
Assuntos
Antivirais/síntese química , Nucleotídeos de Guanina/síntese química , Inibidores da Síntese de Ácido Nucleico/síntese química , Proteínas não Estruturais Virais/antagonistas & inibidores , Alcenos/síntese química , Azidas/síntese química , Hepacivirus/enzimologia , Proteínas não Estruturais Virais/químicaRESUMO
A novel series of 2-(4-sulfonamidophenyl)-indole 3-carboxamides was identified and optimized for activity against the HCV genotype 1b replicon resulting in compounds with potent and selective activity. Further evaluation of this series demonstrated potent activity across HCV genotypes 1a, 2a and 3a. Compound 4z had reduced activity against HCV genotype 1b replicons containing single mutations in the NS4B coding sequence (F98C and V105M) indicating that NS4B is the target. This novel series of 2-(4-sulfonamidophenyl)-indole 3-carboxamides serves as a promising starting point for a pan-genotype HCV discovery program.
Assuntos
Antivirais/química , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Indóis/química , Indóis/farmacologia , Proteínas não Estruturais Virais/metabolismo , Sequência de Aminoácidos , Hepacivirus/química , Hepacivirus/genética , Hepacivirus/metabolismo , Hepatite C/tratamento farmacológico , Humanos , Dados de Sequência Molecular , Mutação , Replicon/efeitos dos fármacos , Sulfonamidas/química , Sulfonamidas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genéticaRESUMO
A structure-activity relationship investigation of various 6-(azaindol-2-yl)pyridine-3-sulfonamides using the HCV replicon cell culture assay led to the identification of a potent series of 7-azaindoles that target the hepatitis C virus NS4B. Compound 2ac, identified via further optimization of the series, has excellent potency against the HCV 1b replicon with an EC50 of 2nM and a selectivity index of >5000 with respect to cellular GAPDH RNA. Compound 2ac also has excellent oral plasma exposure levels in rats, dogs and monkeys and has a favorable liver to plasma distribution profile in rats.
Assuntos
Hepacivirus/enzimologia , Piridinas/química , Piridinas/farmacologia , Sulfonamidas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/química , Antivirais/farmacologia , Cães , Hepacivirus/efeitos dos fármacos , Humanos , Macaca fascicularis , Ratos , Relação Estrutura-AtividadeRESUMO
Starting from indole-based hepatitis C virus (HCV) NS5B polymerase inhibitor lead compound 1, structure modifications were performed at multiple indole substituents to improve potency and pharmacokinetic (PK) properties. Bicyclic quinazolinone was found to be the best substituent at indole nitrogen, while 4,5-furanylindole was identified as the best core. Compound 11 demonstrated excellent potency. Its C2 N,N-dimethylaminoethyl ester prodrug 12 (SCH 900188) demonstrated significant improvement in PK and was selected as the development candidate.
RESUMO
A novel, potent, and orally bioavailable inhibitor of hepatitis C RNA replication targeting NS4B, compound 4t (PTC725), has been identified through chemical optimization of the 6-(indol-2-yl)pyridine-3-sulfonamide 2 to improve DMPK and safety properties. The focus of the SAR investigations has been to identify the optimal combination of substituents at the indole N-1, C-5, and C-6 positions and the sulfonamide group to limit the potential for in vivo oxidative metabolism and to achieve an acceptable pharmacokinetic profile. Compound 4t has excellent potency against the HCV 1b replicon, with an EC50 = 2 nM and a selectivity index of >5000 with respect to cellular GAPDH. Compound 4t has an overall favorable pharmacokinetic profile with oral bioavailability values of 62%, 78%, and 18% in rats, dogs, and monkeys, respectively, as well as favorable tissue distribution properties with a liver to plasma exposure ratio of 25 in rats.
Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Sulfonamidas/farmacologia , Administração Oral , Animais , Antivirais/administração & dosagem , Antivirais/farmacocinética , Área Sob a Curva , Disponibilidade Biológica , Cães , Haplorrinos , Humanos , Ratos , Relação Estrutura-Atividade , Sulfonamidas/administração & dosagem , Sulfonamidas/farmacocinéticaRESUMO
HCV infections are the leading causes for hepatocellular carcinoma and liver transplantation in the United States. Recent advances in drug discovery have identified direct acting antivirals which have significantly improved cure rates in patients. Current efforts are directed towards identification of novel direct acting antiviral targeting different mechanism of actions which could become part of all oral therapies. We recently disclosed the identification of a novel tricyclic indole derived inhibitors of HCV NS5B polymerase that bound to the enzyme close to the active site. In this manuscript we describe further optimization of potency and pharmacokinetics (PK) of these inhibitors to identify compounds in low nM potency against gt-1b. These analogs also demonstrate excellent PK in rats and monkeys when administered as a dimethyl ethyl amino ester prodrug.
Assuntos
Ésteres/farmacocinética , Hepacivirus/efeitos dos fármacos , Indóis/farmacocinética , Proteínas não Estruturais Virais/antagonistas & inibidores , Administração Oral , Animais , Descoberta de Drogas , Ésteres/química , Haplorrinos , Hepacivirus/enzimologia , Humanos , Indóis/química , Pró-Fármacos/farmacologia , Ratos , Relação Estrutura-AtividadeRESUMO
The discovery of lead compound 2e was described. Its covalent binding to HCV NS5B polymerase enzyme was investigated by X-ray analysis. The results of distribution, metabolism and pharmacokinetics were reported. Compound 2e was demonstrated to be potent (replicon GT-1b EC50 = 0.003 µM), highly selective, and safe in in vitro and in vivo assays.
Assuntos
Inibidores Enzimáticos/química , Hepacivirus/enzimologia , Indóis/química , Quinolinas/química , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Cristalografia por Raios X , Cães , Avaliação Pré-Clínica de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/farmacologia , Haplorrinos , Humanos , Indóis/síntese química , Indóis/farmacocinética , Indóis/farmacologia , Masculino , Simulação de Dinâmica Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Quinolinas/síntese química , Quinolinas/farmacocinética , Quinolinas/farmacologia , Ratos , Ratos Sprague-Dawley , Proteínas não Estruturais Virais/metabolismoRESUMO
A novel series of 6-(indol-2-yl)pyridine-3-sulfonamides was prepared and evaluated for their ability to inhibit HCV RNA replication in the HCV replicon cell culture assay. Preliminary optimization of this series furnished compounds with low nanomolar potency against the HCV genotype 1b replicon. Among these, compound 8c has identified as a potent HCV replicon inhibitor (EC50=4 nM) with a selectivity index with respect to cellular GAPDH of more than 2500. Further, compound 8c had a good pharmacokinetic profile in rats with an IV half-life of 6h and oral bioavailability (F) of 62%. Selection of HCV replicon resistance identified an amino acid substitution in HCV NS4B that confers resistance to these compounds. These compounds hold promise as a new chemotype with anti-HCV activity mediated through an underexploited viral target.
Assuntos
Antivirais/farmacologia , Descoberta de Drogas , Hepacivirus/efeitos dos fármacos , Indóis/farmacologia , Piridinas/farmacologia , Sulfonamidas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/administração & dosagem , Antivirais/química , Disponibilidade Biológica , Relação Dose-Resposta a Droga , Hepacivirus/genética , Humanos , Indóis/síntese química , Indóis/química , Testes de Sensibilidade Microbiana , Microssomos Hepáticos/metabolismo , Estrutura Molecular , Piridinas/síntese química , Piridinas/química , Ratos , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/genéticaRESUMO
The characterization of HCV genome has identified various vital functional proteins involved in the life cycle of hepatitis C virus. This has resulted in many novel enzymatic targets that are potential for development of therapeutic agents. The HCV RNA dependent RNA polymerase (HCV NS5B) is one such essential enzyme for HCV replication that has been well characterized and studied by various groups to develop novel therapies for hepatitis C. In this paper, we describe our efforts towards the identification and structure-activity relationship (SAR) of novel tricyclic indole derivatives that bind close to the palm site of the NS5B polymerase. X-ray crystal structure of an inhibitor bound to the polymerase is also described.
Assuntos
Antivirais/química , Antivirais/farmacologia , Hepacivirus/enzimologia , Indóis/química , Indóis/farmacologia , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Sítios de Ligação , Cristalografia por Raios X , Hepacivirus/química , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Humanos , Simulação de Acoplamento Molecular , RNA Polimerase Dependente de RNA/química , RNA Polimerase Dependente de RNA/metabolismo , Relação Estrutura-AtividadeRESUMO
The installation of geminal substitution at the C5' position of the carbosugar in our pyrimidine-derived hepatitis C inhibitor series is reported. SAR studies around the C5' position led to the installation of the dimethyl group as the optimal functionality. An improved route was subsequently designed to access these substitutions. Expanded SAR at the C2 amino position led to the utilization of C2 ethers. These compounds exhibited good potency, high selectivity, and excellent plasma exposure and bioavailability in rodent as well as in higher species.
Assuntos
Antivirais/síntese química , Carboidratos/química , Pirimidinas/química , Animais , Antivirais/química , Antivirais/farmacocinética , Disponibilidade Biológica , Cães , Meia-Vida , Haplorrinos , Hepacivirus/efeitos dos fármacos , Hepacivirus/metabolismo , Pirimidinas/síntese química , Pirimidinas/farmacocinética , Ratos , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacosRESUMO
Introduction of a nitrogen atom into the benzene ring of a previously identified HCV replication (replicase) benzothiazole inhibitor 1, resulted in the discovery of the more potent pyridothiazole analogues 3. The potency and PK properties of the compounds were attenuated by the introductions of various functionalities at the R(1), R(2) or R(3) positions of the molecule (compound 3). Inhibitors 38 and 44 displayed excellent potency, selectivity (GAPDH/MTS CC(50)), PK parameters in all species studied, and cross genotype activity.
Assuntos
Antivirais/química , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Pirimidinas/química , Pirimidinas/farmacologia , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/farmacocinética , Cães , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Humanos , Pirimidinas/farmacocinética , Ratos , Relação Estrutura-Atividade , Tiazóis/química , Tiazóis/farmacocinética , Tiazóis/farmacologiaRESUMO
Based on a previously identified HCV replication (replicase) inhibitor 1, SAR efforts were conducted around the pyrimidine core to improve the potency and pharmacokinetic profile of the inhibitors. A benzothiazole moiety was found to be the optimal substituent at the pyrimidine 5-position. Due to potential reactivity concern, the 4-chloro residue was replaced by a methyl group with some loss in potency and enhanced rat in vivo profile. Extensive investigations at the C-2 position resulted in identification of compound 16 that demonstrated very good replicon potency, selectivity and rodent plasma/target organ concentration. Inhibitor 16 also demonstrated good plasma levels and oral bioavailability in dogs, while monkey exposure was rather low. Chemistry optimization towards a practical route to install the benzothiazole moiety resulted in an efficient direct C-H arylation protocol.
Assuntos
Antivirais/química , Benzotiazóis/química , Hepacivirus/efeitos dos fármacos , Pirimidinas/química , Replicação Viral/efeitos dos fármacos , Animais , Cães , Haplorrinos , Hepacivirus/fisiologia , Metilação , Roedores , Especificidade da EspécieRESUMO
The synthesis of substituted 3,4-dihydrofuranoindoles is reported. These new indole compounds were used to synthesize potent HCV NS5B inhibitors. The binding mode of the dihydrofuranoindole-derived inhibitors was established via X-ray crystallographic studies.
Assuntos
Inibidores Enzimáticos/síntese química , Hepacivirus/efeitos dos fármacos , Indóis/síntese química , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Proteínas não Estruturais Virais/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Hepacivirus/enzimologia , Indóis/farmacologia , Modelos Moleculares , Domínios e Motivos de Interação entre ProteínasRESUMO
Starting from indole-based C-3 pyridone HCV NS5B polymerase inhibitor 2, structure-activity relationship (SAR) investigations of the indole N-1 benzyl moiety were performed. This study led to the discovery of irreversible inhibitors with p-fluoro-sulfone- or p-fluoro-nitro-substituted N-1 benzyl groups which achieved breakthrough replicon assay potency (EC(50) = 1 nM). The formation of a covalent bond with adjacent cysteine-366 thiol was was proved by mass spectroscopy and X-ray crystal structure studies. The C-5 ethyl C-2 carboxylic acid derivative 47 had an excellent oral area-under-the-curve (AUC) of 18 µM·h (10 mg/kg). Its oral exposure in monkeys and dogs was also very good. The NMR ALARM assay, mass spectroscopy experiments, in vitro counter screening, and toxicology assays demonstrated that the covalent bond formation between compound 47 and the protein was highly selective and specific. The overall excellent profile of 47 made it an interesting candidate for further investigation.
Assuntos
Antivirais/síntese química , Hepacivirus/efeitos dos fármacos , Indóis/síntese química , Nitrocompostos/síntese química , Sulfonas/síntese química , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/farmacocinética , Antivirais/farmacologia , Cristalografia por Raios X , Cães , Haplorrinos , Hepacivirus/enzimologia , Indóis/farmacocinética , Indóis/farmacologia , Modelos Moleculares , Estrutura Molecular , Testes de Mutagenicidade , Nitrocompostos/farmacocinética , Nitrocompostos/farmacologia , Piridonas/síntese química , Piridonas/farmacocinética , Piridonas/farmacologia , Ratos , Relação Estrutura-Atividade , Sulfonas/farmacocinética , Sulfonas/farmacologiaRESUMO
Starting with the indole-based C-3 pyridone lead HCV polymerase inhibitor 2, extensive SAR studies were performed at different positions of the indole core. The best C-5 groups were found to be compact and nonpolar moieties and that the C-6 attachments were not affecting potency. Limited N-1 benzyl-type substituent studies indicated that the best substitutions were fluoro or methyl groups at 2' or 5' positions of the benzyl group. To improve pharmacokinetic (PK) properties, acylsulfonamides were incorporated as acid isosteres at the C-2 position. Further optimization of the combination at N-1, C-2, C-5, and C-6 resulted in the identification of compound 56, which had an excellent potency in both NS5B enzyme (IC(50) = 0.008 µM) and cell-based replicon (EC(50) = 0.02 µM) assays and a good oral PK profile with area-under-the curve (AUC) of 14 and 8 µM·h in rats and dogs, respectively. X-ray structure of inhibitor 56 bound to the enzyme was also reported.
Assuntos
Antivirais/síntese química , Hepacivirus/enzimologia , Indóis/síntese química , Sulfonamidas/síntese química , Proteínas não Estruturais Virais/antagonistas & inibidores , Administração Oral , Animais , Antivirais/farmacocinética , Antivirais/farmacologia , Células CACO-2 , Cristalografia por Raios X , Cães , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Humanos , Indóis/química , Indóis/farmacocinética , Indóis/farmacologia , Modelos Moleculares , Estrutura Molecular , Permeabilidade , Ratos , Replicon , Relação Estrutura-Atividade , Sulfonamidas/farmacocinética , Sulfonamidas/farmacologiaRESUMO
A novel method to synthesize tertiary alkyl/aryl sulfides in a mild and regioselective manner from unactivated alkenes using cobalt catalysis is described. The methodology is compatible with sensitive functionalities and is successful with several different types of alkenes and sulfides.