RESUMO
BACKGROUND: The woods of trees of the genus Dalbergia are a frequent cause of allergic contact dermatitis. OBJECTIVES: To describe the different patterns of symptoms and sensitisation to woods of the genus Dalbergia in four patients whose regular work is linked to music, either as performers (two patients) or instrument makers. RESULTS: The patients showed extensive cross-reactivity between the different Dalbergia woods. The two musicians exhibited symptoms exclusively in the contact areas, while the instrument makers showed a pattern of airborne symptoms. The period from sensitisation to the development of symptoms varied greatly among the patients. CONCLUSIONS: The symptoms of allergic contact dermatitis to Dalbergia woods differ markedly depending on the route of contact. Cross-reactivity between the woods of this genus is very wide. The sensitising potential varies between the various Dalbergia woods, which require different contact periods depending on their sensitising power.
RESUMO
BACKGROUND: Leucine-rich repeat kinase 2 (LRRK2) inhibition is a promising therapeutic approach for the treatment of Parkinson's disease (PD). OBJECTIVE: The aim of this study was to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of the potent, selective, CNS-penetrant LRRK2 inhibitor BIIB122 (DNL151) in healthy participants and patients with PD. METHODS: Two randomized, double-blind, placebo-controlled studies were completed. The phase 1 study (DNLI-C-0001) evaluated single and multiple doses of BIIB122 for up to 28 days in healthy participants. The phase 1b study (DNLI-C-0003) evaluated BIIB122 for 28 days in patients with mild to moderate PD. The primary objectives were to investigate the safety, tolerability, and plasma pharmacokinetics of BIIB122. Pharmacodynamic outcomes included peripheral and central target inhibition and lysosomal pathway engagement biomarkers. RESULTS: A total of 186/184 healthy participants (146/145 BIIB122, 40/39 placebo) and 36/36 patients (26/26 BIIB122, 10/10 placebo) were randomized/treated in the phase 1 and phase 1b studies, respectively. In both studies, BIIB122 was generally well tolerated; no serious adverse events were reported, and the majority of treatment-emergent adverse events were mild. BIIB122 cerebrospinal fluid/unbound plasma concentration ratio was ~1 (range, 0.7-1.8). Dose-dependent median reductions from baseline were observed in whole-blood phosphorylated serine 935 LRRK2 (≤98%), peripheral blood mononuclear cell phosphorylated threonine 73 pRab10 (≤93%), cerebrospinal fluid total LRRK2 (≤50%), and urine bis (monoacylglycerol) phosphate (≤74%). CONCLUSIONS: At generally safe and well-tolerated doses, BIIB122 achieved substantial peripheral LRRK2 kinase inhibition and modulation of lysosomal pathways downstream of LRRK2, with evidence of CNS distribution and target inhibition. These studies support continued investigation of LRRK2 inhibition with BIIB122 for the treatment of PD. © 2023 Denali Therapeutics Inc and The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Leucócitos Mononucleares/metabolismo , Voluntários Saudáveis , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Biomarcadores/metabolismo , MutaçãoRESUMO
BACKGROUND: Iodinated contrast media produce non-immediate hypersensitivity reactions (NIHR). The goal of this prospective study was to determine the utility of skin tests and the subsequent tolerance to negative skin-tested iodinated contrasts in patients with NIHR caused by iomeprol. METHODS: Prick and intradermal tests with iomeprol, iopamidol, iopromide, and iobitridol were performed in all patients. IV challenge with the causative contrast (iomeprol in 90%) was made if skin tests were negative. In case of a positive skin test with the causal contrast, or a positive challenge test with it, IV challenge test with an alternative, negative skin-tested contrast was performed in all patients. RESULTS: Skin tests were positive in 47.6% (20/42) of patients with NIHR induced by iomeprol. Of the 66 challenge tests performed with negative skin-tested iodinated contrasts, tolerance was confirmed in 35 (53%): 32 iomeron, 2 iobitridol, 1 iopamidol. Cross-reactivity between iomeprol and iopamidol was 22% (4/20 in patients with positive skin tests and 5/21 in patients with negative skin tests). CONCLUSIONS: Sensitivity of the skin tests was less than 50% NIHRs due to iomeprol, while the negative predictive value of skin tests in patients who tolerated challenges with alternative contrasts (mainly iopamidol) was 53% (35 tolerated out of 66 performed). The cross-reactivity between iomeprol and iopamidol is high.
Assuntos
Hipersensibilidade Imediata , Compostos de Iodo , Humanos , Iopamidol/efeitos adversos , Meios de Contraste/efeitos adversos , Estudos Prospectivos , Testes Cutâneos , Compostos de Iodo/efeitos adversos , Hipersensibilidade Imediata/diagnóstico , Hipersensibilidade Imediata/etiologiaRESUMO
BACKGROUND: Fixed drug eruption (FDE) is a characteristic form of intraepidermal CD8+ T cell-mediated drug reaction, with repeated appearance of isolated or multiple skin lesions in the same location after receiving the offending drug. Non-steroidal anti-inflammatory drugs (NSAID) are the most common cause. Selective inhibitors of inducible cyclooxygenase 2 (COX-2) provoke a lesser degree of allergic or idiosyncratic adverse reactions than conventional NSAID, but they can cause skin reactions of variable severity. OBJECTIVE: Etoricoxib has been related to a variety of unusual skin reactions, including several reports of FDE. METHODS: We perfomed epicutaneous test to diagnose patients with suspected etoricoxib fixe drug rash due to clinical features and reproducibility on at least two occasions. RESULTS: We present seven new cases of etoricoxib-induced fixed drug eruption, with a diagnosis based on clinical presentation. This diagnosis was confirmed by an etoricoxib-positive lesional patch test in six cases and by a positive low-dose oral challenge in the other one. Two patients showed negative patch tests with celecoxib (10% in pet.) on the residual lesions, and oral tolerance was confirmed in one. CONCLUSION: To our knowledge, this is the largest series on FDE induced by etoricoxib reported to date.
Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Inibidores de Ciclo-Oxigenase 2/efeitos adversos , Dermatite Alérgica de Contato/etiologia , Toxidermias/etiologia , Etoricoxib/efeitos adversos , Adulto , Idoso , Dermatite Alérgica de Contato/diagnóstico , Toxidermias/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes do EmplastroRESUMO
Searching for high-performance permanent magnets components with no limitation in shape and dimensions is highly desired to overcome the present design and manufacturing restrictions, which affect the efficiency of the final devices in energy, automotive and aerospace sectors. Advanced 3D-printing of composite materials and related technologies is an incipient route to achieve functional structures avoiding the limitations of traditional manufacturing. Gas-atomized MnAlC particles combined with polymer have been used in this work for fabricating scalable rare earth-free permanent magnet composites and extruded flexible filaments with continuous length exceeding 10 m. Solution casting has been used to synthesize homogeneous composites with tuned particles content, made of a polyethylene (PE) matrix embedding quasi-spherical particles of the ferromagnetic τ-MnAlC phase. A maximum filling factor of 86.5 and 72.3% has been obtained for the composite and the filament after extrusion, respectively. The magnetic measurements reveal no deterioration of the properties of the MnAlC particles after the composite synthesis and filament extrusion. The produced MnAlC/PE materials will serve as precursors for an efficient and scalable design and fabrication of end-products by different processing techniques (polymerized cold-compacted magnets and 3D-printing, respectively) in view of technological applications (from micro electromechanical systems to energy and transport applications).
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Acrilatos/efeitos adversos , Dermatite Alérgica de Contato/etiologia , Géis/efeitos adversos , Ultrassonografia , Ureia/análogos & derivados , Acrilatos/análise , Adulto , Dermatite Alérgica de Contato/diagnóstico , Emulsificantes/efeitos adversos , Emulsificantes/análise , Feminino , Géis/química , Humanos , Masculino , Pessoa de Meia-Idade , Testes do Emplastro , Conservantes Farmacêuticos/efeitos adversos , Conservantes Farmacêuticos/análise , Ureia/efeitos adversos , Ureia/análiseRESUMO
The discovery of a novel series of pyrrolopyrazines as JAK inhibitors with comparable enzyme and cellular activity to tofacitinib is described. The series was identified using a scaffold hopping approach aided by structure based drug design using principles of intramolecular hydrogen bonding for conformational restriction and targeting specific pockets for modulating kinase activity.
Assuntos
Janus Quinase 3/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Pirazinas/química , Pirróis/química , Desenho de Fármacos , Humanos , Janus Quinase 3/metabolismo , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Fosforilação , Piperidinas/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Relação Estrutura-AtividadeRESUMO
Eukaryotic translation initiation factor 2B (eIF2B) is a key component of the integrated stress response (ISR), which regulates protein synthesis and stress granule formation in response to cellular insult. Modulation of the ISR has been proposed as a therapeutic strategy for treatment of neurodegenerative diseases such as vanishing white matter (VWM) disease and amyotrophic lateral sclerosis (ALS) based on its ability to improve cellular homeostasis and prevent neuronal degeneration. Herein, we report the small-molecule discovery campaign that identified potent, selective, and CNS-penetrant eIF2B activators using both structure- and ligand-based drug design. These discovery efforts culminated in the identification of DNL343, which demonstrated a desirable preclinical drug profile, including a long half-life and high oral bioavailability across preclinical species. DNL343 was progressed into clinical studies and is currently undergoing evaluation in late-stage clinical trials for ALS.
Assuntos
Esclerose Lateral Amiotrófica , Leucoencefalopatias , Doenças Neurodegenerativas , Humanos , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/metabolismo , Mutação , Fator de Iniciação 2B em Eucariotos/genética , Fator de Iniciação 2B em Eucariotos/metabolismo , Encéfalo/metabolismo , Leucoencefalopatias/metabolismoRESUMO
We report the discovery of a novel series of ATP-competitive Janus kinase 3 (JAK3) inhibitors based on the 5H-pyrrolo[2,3-b]pyrazine scaffold. The initial leads in this series, compounds 1a and 1h, showed promising potencies, but a lack of selectivity against other isoforms in the JAK family. Computational and crystallographic analysis suggested that the phenyl ether moiety possessed a favorable vector to achieve selectivity. Exploration of this vector resulted in the identification of 12b and 12d, as potent JAK3 inhibitors, demonstrating improved JAK family and kinase selectivity.
Assuntos
Janus Quinase 3/antagonistas & inibidores , Éteres Fenílicos/química , Inibidores de Proteínas Quinases/química , Piridazinas/química , Pirróis/química , Sítios de Ligação , Domínio Catalítico , Avaliação Pré-Clínica de Medicamentos , Janus Quinase 3/metabolismo , Simulação de Acoplamento Molecular , Éteres Fenílicos/síntese química , Éteres Fenílicos/metabolismo , Ligação Proteica , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/metabolismo , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/metabolismo , Relação Estrutura-AtividadeRESUMO
Dual leucine zipper kinase (DLK) and leucine zipper-bearing kinase (LZK) are regulators of neuronal degeneration and axon growth. Therefore, there is a considerable interest in developing DLK/LZK inhibitors for neurodegenerative diseases. Herein, we use ligand- and structure-based drug design approaches for identifying novel amino-pyrazine inhibitors of DLK/LZK. DN-1289 (14), a potent and selective dual DLK/LZK inhibitor, demonstrated excellent in vivo plasma half-life across species and is anticipated to freely penetrate the central nervous system with no brain impairment based on in vivo rodent pharmacokinetic studies and human in vitro transporter data. Proximal target engagement and disease relevant pathway biomarkers were also favorably regulated in an in vivo model of amyotrophic lateral sclerosis.
Assuntos
Esclerose Lateral Amiotrófica , Doenças Neurodegenerativas , Humanos , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/metabolismo , Zíper de Leucina , MAP Quinase Quinase Quinases , Sistema Nervoso Central/metabolismo , Encéfalo/metabolismo , Doenças Neurodegenerativas/metabolismoRESUMO
Mutations in leucine-rich repeat kinase 2 (LRRK2) are the most common genetic risk factors for Parkinson's disease (PD). Increased LRRK2 kinase activity is thought to impair lysosomal function and may contribute to the pathogenesis of PD. Thus, inhibition of LRRK2 is a potential disease-modifying therapeutic strategy for PD. DNL201 is an investigational, first-in-class, CNS-penetrant, selective, ATP-competitive, small-molecule LRRK2 kinase inhibitor. In preclinical models, DNL201 inhibited LRRK2 kinase activity as evidenced by reduced phosphorylation of both LRRK2 at serine-935 (pS935) and Rab10 at threonine-73 (pT73), a direct substrate of LRRK2. Inhibition of LRRK2 by DNL201 demonstrated improved lysosomal function in cellular models of disease, including primary mouse astrocytes and fibroblasts from patients with Gaucher disease. Chronic administration of DNL201 to cynomolgus macaques at pharmacologically relevant doses was not associated with adverse findings. In phase 1 and phase 1b clinical trials in 122 healthy volunteers and in 28 patients with PD, respectively, DNL201 at single and multiple doses inhibited LRRK2 and was well tolerated at doses demonstrating LRRK2 pathway engagement and alteration of downstream lysosomal biomarkers. Robust cerebrospinal fluid penetration of DNL201 was observed in both healthy volunteers and patients with PD. These data support the hypothesis that LRRK2 inhibition has the potential to correct lysosomal dysfunction in patients with PD at doses that are generally safe and well tolerated, warranting further clinical development of LRRK2 inhibitors as a therapeutic modality for PD.
Assuntos
Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Doença de Parkinson , Animais , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/antagonistas & inibidores , Lisossomos/metabolismo , Camundongos , Mutação , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , FosforilaçãoRESUMO
BACKGROUND: COVID-19 cutaneous manifestations have been recently described and classified in five different clinical patterns, including acral erythema-edema (pseudo-chilblain), maculopapular exanthemas, vesicular eruptions, urticarial lesions, and livedo or necrosis. OBJECTIVES: The objective of this study was to examine the skin of hospitalized patients with a confirmed diagnosis of COVID-19 disease and describe the real prevalence of skin manifestations. METHODS: A cross-sectional study, which included hospitalized patients in Cruces University Hospital from April 14-30, 2020, with a laboratory-confirmed diagnosis of COVID-19 (with polymerase chain reaction and/or serology tests), was conducted. Entire body surface examination was performed by experienced dermatologists to search for cutaneous manifestations related to COVID-19 disease. RESULTS: From a sample of 75 patients, 14 (18.7%) developed cutaneous manifestations possibly related to COVID-19. We found six patients with acral erythema-edema (pseudo-chilblain) (42.8%), four patients with maculopapular exanthemas (28.6%), two patients with urticarial lesions (14.3%), one patient with livedo reticularis-like lesions (7.15%), and one patient with vesicular eruption (7.15%). CONCLUSIONS: Our study provides a more plausible relationship between the main cutaneous patterns and COVID-19 in hospitalized patients as all of them had a confirmatory laboratory test. Skin manifestations are frequent but mild with spontaneous resolution. These findings are nonspecific and can be similar to other viral infections and adverse drug reactions in hospitalized patients.
Assuntos
COVID-19/complicações , Edema/virologia , Dermatopatias/virologia , Idoso , Vesícula/virologia , Estudos Transversais , Eritema/virologia , Exantema/virologia , Feminino , Hospitalização , Humanos , Livedo Reticular/virologia , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Centros de Atenção Terciária , Urticária/virologiaRESUMO
LpxD, acyl-ACP-dependent N-acyltransferase, is the third enzyme of lipid A biosynthesis in Gram-negative bacteria. A recent probe-based screen identified several compounds, including 6359-0284 (compound 1), that inhibit the enzymatic activity of Escherichia coli (E. coli) LpxD. Here, we use these inhibitors to chemically validate LpxD as an attractive antibacterial target. We first found that compound 1 was oxidized in solution to the more stable aromatized tetrahydro-pyrazolo-quinolinone compound 1o. From the Escherichia coli strain deficient in efflux, we isolated a mutant that was less susceptible to compound 1o and had an lpxD missense mutation (Gly268Cys), supporting the cellular on-target activity. Using surface plasma resonance, we showed direct binding to E. coli LpxD for compound 1o and other reported LpxD inhibitors in vitro. Furthermore, we determined eight cocrystal structures of E. coli LpxD/inhibitor complexes. These costructures pinpointed the 4'-phosphopantetheine binding site as the common ligand binding hotspot, where hydrogen bonds to Gly269 and/or Gly287 were important for inhibitor binding. In addition, the LpxD/compound 1o costructure rationalized the reduced activity of compound 1o in the LpxDGly268Cys mutant. Moreover, we obtained the LpxD structure in complex with a previously reported LpxA/LpxD dual targeting peptide inhibitor, RJPXD33, providing structural rationale for the unique dual targeting properties of this peptide. Given that the active site residues of LpxD are conserved in multidrug resistant Enterobacteriaceae, this work paves the way for future LpxD drug discovery efforts combating these Gram-negative pathogens.
Assuntos
Aciltransferases , Proteínas de Escherichia coli , Escherichia coli , Aciltransferases/antagonistas & inibidores , Aciltransferases/genética , Sítios de Ligação , Escherichia coli/enzimologia , Escherichia coli/genética , Proteínas de Escherichia coli/antagonistas & inibidores , Lipídeo A , LipopolissacarídeosRESUMO
Since their discovery over 5 decades ago, quinolone antibiotics have found enormous success as broad spectrum agents that exert their activity through dual inhibition of bacterial DNA gyrase and topoisomerase IV. Increasing rates of resistance, driven largely by target-based mutations in the GyrA/ParC quinolone resistance determining region, have eroded the utility and threaten the future use of this vital class of antibiotics. Herein we describe the discovery and optimization of a series of 4-(aminomethyl)quinolin-2(1H)-ones, exemplified by 34, that inhibit bacterial DNA gyrase and topoisomerase IV and display potent activity against ciprofloxacin-resistant Gram-negative pathogens. X-ray crystallography reveals that 34 occupies the classical quinolone binding site in the topoisomerase IV-DNA cleavage complex but does not form significant contacts with residues in the quinolone resistance determining region.
Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Fluoroquinolonas/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Inibidores da Topoisomerase II/farmacologia , Antibacterianos/síntese química , Antibacterianos/metabolismo , Antibacterianos/toxicidade , Sítios de Ligação , Linhagem Celular Tumoral , DNA Girase/metabolismo , DNA Topoisomerase IV/antagonistas & inibidores , DNA Topoisomerase IV/química , Fluoroquinolonas/síntese química , Fluoroquinolonas/metabolismo , Fluoroquinolonas/toxicidade , Bactérias Gram-Negativas/enzimologia , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Inibidores da Topoisomerase II/síntese química , Inibidores da Topoisomerase II/metabolismo , Inibidores da Topoisomerase II/toxicidadeRESUMO
A series of benzo[d]isothiazole-1,1-dioxides were designed and evaluated as inhibitors of HCV polymerase NS5B. Structure-based design led to the incorporation of a high affinity methyl sulfonamide group. Structure-activity relationship (SAR) studies of this series revealed analogues with submicromolar potencies in the HCV replicon assay and moderate pharmacokinetic properties. SAR studies combined with structure based drug design focused on the sulfonamide region led to a novel and potent cyclic analogue.
Assuntos
Antivirais/síntese química , Hepacivirus/efeitos dos fármacos , Tiazóis/química , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/química , Antivirais/farmacocinética , Sítios de Ligação , Cristalografia por Raios X , Haplorrinos , Ratos , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/farmacocinética , Proteínas não Estruturais Virais/metabolismoRESUMO
Benzothiazine-substituted tetramic acids were discovered as highly potent non-nucleoside inhibitors of HCV NS5B polymerase. X-ray crystallography studies confirmed the binding mode of these inhibitors with HCV NS5B polymerase. Rational optimization of time dependent inactivation of CYP 3A4 and clearance was accomplished by incorporation of electron-withdrawing groups to the benzothiazine core.
Assuntos
Antivirais/síntese química , Hepacivirus/efeitos dos fármacos , Pirrolidinonas/química , Tiazinas/química , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/química , Antivirais/farmacocinética , Sítios de Ligação , Cristalografia por Raios X , Pirrolidinonas/síntese química , Pirrolidinonas/farmacocinética , Ratos , Relação Estrutura-Atividade , Proteínas não Estruturais Virais/metabolismoRESUMO
A new series of benzothiazine-substituted quinolinediones were evaluated as inhibitors of HCV polymerase NS5B. SAR studies on this series revealed a methyl sulfonamide group as a high affinity feature. Analogues with this group showed submicromolar potencies in the HCV cell based replicon assay. Pharmacokinetic and toxicology studies were also performed on a selected compound (34) to evaluate in vivo properties of this new class of inhibitors of HCV NS5B polymerase.
Assuntos
Antivirais/química , RNA Polimerases Dirigidas por DNA/antagonistas & inibidores , Inibidores Enzimáticos/química , Hepacivirus/efeitos dos fármacos , Quinolinas/química , Quinolonas/química , Tiazinas/química , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/síntese química , Antivirais/farmacocinética , Simulação por Computador , Cristalografia por Raios X , RNA Polimerases Dirigidas por DNA/metabolismo , Cães , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacocinética , Humanos , Quinolinas/síntese química , Quinolinas/farmacocinética , Quinolonas/síntese química , Quinolonas/farmacologia , Ratos , Relação Estrutura-Atividade , Tiazinas/síntese química , Tiazinas/farmacologia , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacosRESUMO
Drug-resistant Gram-negative bacteria are of increasing concern worldwide. Novel antibiotics are needed, but their development is complicated by the requirement to simultaneously optimize molecules for target affinity and cellular potency, which can result in divergent structure-activity relationships (SARs). These challenges were exemplified during our attempts to optimize inhibitors of the bacterial enzyme CoaD originally identified through a biochemical screen. To facilitate lead optimization, we developed mass spectroscopy assays based on the hypothesis that levels of CoA metabolites would reflect the cellular enzymatic activity of CoaD. Using these methods, we were able to monitor the effects of cellular enzyme inhibition at compound concentrations up to 100-fold below the minimum inhibitory concentration (MIC), a common metric of growth inhibition. Furthermore, we generated a panel of efflux pump mutants to dissect the susceptibility of a representative CoaD inhibitor to efflux. These approaches allowed for a nuanced understanding of the permeability and efflux liabilities of the series and helped guide optimization efforts to achieve measurable MICs against wild-type E. coli.
Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Metabolômica/métodos , Nucleotidiltransferases/antagonistas & inibidores , Antibacterianos/síntese química , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Relação Estrutura-AtividadeRESUMO
In the preceding manuscript [ Moreau et al. 2018 , 10.1021/acs.jmedchem.7b01691 ] we described a successful fragment-based lead discovery (FBLD) strategy for discovery of bacterial phosphopantetheine adenylyltransferase inhibitors (PPAT, CoaD). Following several rounds of optimization two promising lead compounds were identified: triazolopyrimidinone 3 and 4-azabenzimidazole 4. Here we disclose our efforts to further optimize these two leads for on-target potency and Gram-negative cellular activity. Enabled by a robust X-ray crystallography system, our structure-based inhibitor design approach delivered compounds with biochemical potencies 4-5 orders of magnitude greater than their respective fragment starting points. Additional optimization was guided by observations on bacterial permeability and physicochemical properties, which ultimately led to the identification of PPAT inhibitors with cellular activity against wild-type E. coli.
Assuntos
Antibacterianos/farmacologia , Inibidores Enzimáticos/farmacologia , Proteínas de Escherichia coli/antagonistas & inibidores , Compostos Heterocíclicos com 2 Anéis/farmacologia , Nucleotidiltransferases/antagonistas & inibidores , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/metabolismo , Benzimidazóis/síntese química , Benzimidazóis/química , Benzimidazóis/metabolismo , Benzimidazóis/farmacologia , Sítios de Ligação , Descoberta de Drogas , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Compostos Heterocíclicos com 2 Anéis/síntese química , Compostos Heterocíclicos com 2 Anéis/química , Compostos Heterocíclicos com 2 Anéis/metabolismo , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mutação , Nucleotidiltransferases/química , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Ligação Proteica , Pirimidinonas/síntese química , Pirimidinonas/química , Pirimidinonas/metabolismo , Pirimidinonas/farmacologia , Triazóis/síntese química , Triazóis/química , Triazóis/metabolismo , Triazóis/farmacologiaRESUMO
The discovery and development of new antibiotics capable of curing infections due to multidrug-resistant and pandrug-resistant Gram-negative bacteria are a major challenge with fundamental importance to our global healthcare system. Part of our broad program at Novartis to address this urgent, unmet need includes the search for new agents that inhibit novel bacterial targets. Here we report the discovery and hit-to-lead optimization of new inhibitors of phosphopantetheine adenylyltransferase (PPAT) from Gram-negative bacteria. Utilizing a fragment-based screening approach, we discovered a number of unique scaffolds capable of interacting with the pantetheine site of E. coli PPAT and inhibiting enzymatic activity, including triazolopyrimidinone 6. Structure-based optimization resulted in the identification of two lead compounds as selective, small molecule inhibitors of bacterial PPAT: triazolopyrimidinone 53 and azabenzimidazole 54 efficiently inhibited E. coli and P. aeruginosa PPAT and displayed modest cellular potency against the efflux-deficient E. coli Δ tolC mutant strain.