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1.
J Biopharm Stat ; 33(6): 800-811, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36637189

RESUMO

With the development of novel treatment therapies as well as evolving and innovative approaches to conduct clinical trials, the landscape of pediatric oncology drug development has dramatically changed in recent years. Despite this change, approvals for new drugs and labeling updates to ensure availability of proper treatment for pediatric patients with cancer remain slow. The context of drug development in pediatric tumors has also changed with regulatory initiatives in the US and Europe, creating a great need for faster development of novel drugs. Today, conventional study designs have been replaced or complemented by novel clinical trial designs, such as master protocols and platform trials, to optimize cancer drug development and enable faster regulatory approval. The iMATRIX platform is a mechanism-of-action (MOA)-based phase 1/2 trial framework for concurrently studying multiple molecules across a range of relevant pediatric tumor types, taking into account the biology of each pediatric tumor type. Six studies have been conducted, ongoing, or planned on the iMATRIX platform - investigating atezolizumab, cobimetinib, entrectinib, idasanutlin, alectinib, and glofitamab. A brief overview of study designs and characteristics are shared in this article, along with learnings from them.


Assuntos
Oncologia , Neoplasias , Humanos , Criança , Oncologia/métodos , Neoplasias/tratamento farmacológico , Desenvolvimento de Medicamentos , Biologia
2.
Org Biomol Chem ; 18(20): 3893-3897, 2020 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-32392272

RESUMO

A synthesis of unprecedented and stable glycosyl sulfoximines is reported. The developed strategies represent the first example of highly stereoselective sulfoximine formation directly from thioglycosides. This synthetic protocol has been tested on several ß-thioglycosides bearing different aromatics and alkyls as S-substituents, and bearing glucose, mannose and galactose as glycosyl units. The process has been extended to a lactose derived thioglycoside and to a glucose derived sulfenamide. The process was chemo- and stereoselective, and X-ray analysis confirmed the structure and provided stereochemical information on the configuration at the sulfur atom. A model for the stereochemical outcome is proposed based on the steric environment of the sulfide.

3.
Front Chem ; 7: 614, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31572708

RESUMO

A new synthetic route to N-alkyl-2-acylazetidines was developed through a highly stereoselective addition of organolithiums to N-alkyl-2-oxazolinylazetidines followed by acidic hydrolysis of the resulting oxazolidine intermediates. This study revealed an unusual reactivity of the C=N bond of the oxazoline group when reacted with organolithiums in a non-polar solvent such as toluene. The observed reactivity has been explained considering the role of the nitrogen lone pair of the azetidine ring as well as of the oxazolinyl group in promoting a complexation of the organolithium, thus ending up with the addition to the C=N double bond. The high level of stereoselectivity in this addition is supported by DFT calculations and NMR investigations, and a model is proposed for the formation of the oxazolidine intermediates, that have been isolated and fully characterized. Upon acidic conditions, the oxazolidine moieties were readily converted into 2-acylazetidines. This synthetic approach has been applied for the preparation of highly enantioenriched 2-acylazetidines starting from chiral not racemic N-alkyl-2-oxazolinylazetidines.

4.
Chem Commun (Camb) ; 55(58): 8430-8433, 2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31259351

RESUMO

An unprecedented direct fluorocyclopropanation of allylic alcohols is reported. This simple method involves the not so elusive fluoroiodomethyllithium, a carbenoidic intermediate that under the developed conditions discloses its electrophilic nature. Gratifyingly, the reaction turned out to be highly chemo- and stereoselective, and DFT calculations provided insights into the structure and nature of this new type of carbenoid.

5.
Chem Asian J ; 14(17): 3011-3018, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31319007

RESUMO

The use of graphene derivatives as supports improves the properties of heterogeneous catalysts, with graphene oxide (GO) being the most frequently employed. To explore greener possibilities as well as to get some insights into the role of the different graphenic supports (GO, rGO, carbon black, and graphite nanoplatelets), we prepared, under the same standard conditions, a variety of heterogeneous Cu catalysts and systematically evaluated their composition and catalytic activity in azide-alkyne cycloadditions as a model reaction. The use of sustainable graphite nanoplatelets (GNPs) afforded a stable CuI catalyst with good recyclability properties, which are compatible with flow conditions, and able to catalyze other reactions such as the regio- and stereoselective sulfonylation of alkynes (addition reaction) and the Meerwein arylation (single electron transfer process).

6.
Top Curr Chem (Cham) ; 376(6): 46, 2018 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-30470973

RESUMO

Flow chemistry and heterogenous catalysis hold incredible potential from a sustainability point of view and from a green perspective. In fact, if heterogenous catalysts are required by the chemical industry for their efficiency, on the other hand, heterogenous flow catalysis would allow performing greener and more efficient chemistry at an industrial level. In the context of sustainable flow chemistry, in this chapter we report and discuss selected examples recently published in the specialized literature on the use of supported organic and organometallic catalysts for continuous flow synthesis. The use in chemo- and stereoselective synthesis, as well as versatility and robustness of the newly developed supported catalysts are discussed.


Assuntos
Química Verde , Compostos Orgânicos/química , Compostos Organometálicos/química , Polímeros/síntese química , Catálise , Estrutura Molecular , Polímeros/química , Estereoisomerismo
7.
PLoS One ; 13(5): e0196858, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29723285

RESUMO

BACKGROUND: Chromogranin A (CgA) is a plasma biomarker widely used in the follow-up of patients with neuroendocrine neoplasms (NENs). However, its accuracy as a tumor biomarker is relatively low because plasma CgA can increase also in patients with other diseases or in subjects treated with proton-pump inhibitors (PPIs), a class of widely-used drugs. METHODS: In the attempt to identify a more reliable biomarker for NENs, we investigated, by ELISA, the circulating levels of full-length CgA (CgA1-439) and of various CgA-derived fragments in 17 patients with ileal or pancreatic NENs, 10 healthy controls, and 21 healthy volunteers before and after treatment with PPIs. RESULTS: Patients with ileal or pancreatic NENs showed increased plasma levels of total-CgA and CgA1-76 fragment (vasostatin-1, VS-1) compared to controls [median (25th-75th-percentiles); total-CgA: 1.85 nM (1.01-4.28) vs 0.75 nM (0.52-0.89), p = 0.004; VS-1: 2.76 nM (1.09-7.10) vs 0.29 nM (0.26-0.32), p<0.001, respectively], but not of CgA1-439 or CgA1-373 fragment. VS-1 positively correlated with total-CgA (r = 0.65, p<0.001). The Receiver Operating Characteristic area under the curve was 0.9935 for VS-1 and 0.8824 for total-CgA (p = 0.067). Treatment of patients with somatostatin analogues decreased both total-CgA and VS-1. In contrast, administration of PPIs increased the plasma levels of total-CgA, but not of VS-1. CONCLUSION: These findings suggest that plasma VS-1 is a novel biomarker for ileal and pancreatic NENs. Considering that VS-1 is a well-defined fragment not induced by proton-pump inhibitors, this polypeptide might represent a biomarker for NENs diagnosis and follow-up more accurate and easier to standardize than CgA.


Assuntos
Biomarcadores Tumorais/sangue , Cromogranina A/sangue , Neoplasias do Íleo/diagnóstico , Tumores Neuroendócrinos/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Fragmentos de Peptídeos/sangue , 2-Piridinilmetilsulfinilbenzimidazóis/administração & dosagem , Idoso , Antineoplásicos/uso terapêutico , Área Sob a Curva , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Cromogranina A/genética , Feminino , Expressão Gênica , Humanos , Neoplasias do Íleo/sangue , Neoplasias do Íleo/genética , Neoplasias do Íleo/patologia , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/sangue , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/patologia , Octreotida/uso terapêutico , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Pantoprazol , Fragmentos de Peptídeos/genética , Prognóstico , Inibidores da Bomba de Prótons/administração & dosagem , Curva ROC , Somatostatina/administração & dosagem , Somatostatina/análogos & derivados
8.
ACS Omega ; 3(11): 14841-14848, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31458153

RESUMO

We report herein a synthetic protocol for the preparation of 1,3-dibromo-1,1-difluoro-2-propanone, a new synthon used for the first time in a reaction with aromatic amines and sodium thiocyanate, leading to thiazoles which are useful candidates in drug discovery programs. The new synthon allows to introduce a bromodifluoromethyl group at the C4 of the thiazole, and it is amenable of further transformation such as the Br/F exchange useful in radiopharmaceutics. Application of the strategy to the preparation of a precursor of the biologically relevant DF2755Y is also reported.

9.
Cardiovasc Revasc Med ; 19(3 Pt A): 263-267, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29122526

RESUMO

INTRODUCTION: Refractory Angina Pectoris (RAP) dramatically affects patients' life quality and medical costs. External Shockwave Myocardial Revascularization (ESMR) improves the cardiac blood flow thanks to its pro-angiogenetic action on ischaemic tissues. We hereby describe our experience of ESMR in RAP patients. MATERIALS AND METHODS: This is a retrospective study encompassing all patients referred to OSR for RAP treatment. Efficacy of ESMR was assessed considering the difference between pre and post therapy data in SAQ score and CCS, stress test performance, 24h ECG monitoring, NT-proBNP and echocardiographic measures. RESULTS: From a total of 97 patients with RAP, 19 patients underwent ESMR, whereas 4 were considered as control group. After the end of the treatment, ESWT group showed a significant improvement in CCS class (-1.32±0.58; p<0.001) and in each of the five variables of the SAQ score (p<0.05). Patients also improved their exercise duration (50,74±29.40 seconds; p<0,001) and double product (1340,53±1321,77; p<0,001) and reduced the number of daily ST segment depression (-1,16±1,01; p<0,01). Ejection Fraction (2,05±1,84%; p<0,01) and Cardiac Output (0,20±0,28L, p<0,01) improved too. No changes were documented in the control group. CONCLUSION: ESMR is an efficient therapy for refractory angina capable to improve both symptoms and instrumental tests.


Assuntos
Angina Pectoris/terapia , Tratamento por Ondas de Choque Extracorpóreas , Idoso , Angina Pectoris/diagnóstico , Angina Pectoris/fisiopatologia , Circulação Coronária , Tolerância ao Exercício , Tratamento por Ondas de Choque Extracorpóreas/efeitos adversos , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
10.
Org Biomol Chem ; 15(23): 5000-5015, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28567461

RESUMO

The regioselective functionalization of four- and six-membered cyclic sulfones was investigated using a lithiation/electrophile trapping strategy. The protocol features an interesting eco-compatibility profile because of the use of 2-MeTHF as a solvent (more eco-friendly than other organic solvents) and n-hexyllithium as a lithiating agent safer than other alkyllithium compounds. Several derivatives were prepared with different stereochemistry and substitution patterns. A number of selected derivatives, spanning a range of 5 log P units, were characterized for their lipophilicity through RP-HPLC. A good linear correlation, with a slope close to 1.0, was observed between the experimentally determined RP-HPLC lipophilicity parameters (log k'w) and calculated log P (clog P) values, whereas a systematic difference in absolute values between the chromatographic parameters and in silico lipophilicity descriptors can be attributed mainly to silanophilic interactions between the H-bond acceptor SO2 group and free silanol groups on silica-based C18 columns, which results in increased retention times.

11.
Chem Commun (Camb) ; 53(2): 348-351, 2016 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-27929152

RESUMO

Direct synthesis of NH-sulfoximines from sulfides has been achieved through O and NH transfer in the same reaction, occurring with complete selectivity. The reaction is mediated by bisacetoxyiodobenzene under simple conditions and employs inexpensive N-sources. Preliminary studies indicate that NH-transfer is likely to be first, followed by oxidation, but the reaction proceeds successfully in either order. A wide range of functional groups and biologically relevant compounds are tolerated. The use of AcO15NH4 affords 15N-labeled compounds.

12.
Chem Commun (Camb) ; 52(61): 9554-7, 2016 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-27383138

RESUMO

Tertiary butyl esters find large applications in synthetic organic chemistry. A straightforward method for the direct introduction of the tert-butoxycarbonyl group into a variety of organic compounds has been developed using flow microreactor systems. The resultant flow process was more efficient, versatile and sustainable compared to the batch.

13.
Toxicol In Vitro ; 34: 171-178, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27075777

RESUMO

Titanium dioxide (TiO2) nanoparticles (NPs) are manufactured worldwide in large quantities for use in a wide range of applications. Evaluating the hazards associated with TiO2 NPs is crucial as it enables risk assessment related to human and environmental exposure. In this study the in vitro human toxicity of a set of TiO2 NPs modified with acetic, oleic and boric acids were studied in order to assess the hazard in view of a future scale-up of the synthesis. The surface reactivity of the powders under simulated solar illumination and in the dark has been evaluated by means of EPR spectroscopy. Human bronchial epithelial cells (BEAS-2B) have been chosen as a model for lung epithelium. Cytotoxicity has been assessed by measuring the cells membrane integrity by lactate dehydrogenase (LDH) assay, and the inflammatory response evaluated as nitric oxide (NO) and TNF-α production, and oxidative stress measured as intracellular reduced glutathione (GSH) levels, and induced lipoperoxidation. Aeroxide P25 was used for comparison. The results demonstrated a low photoreactivity and toxic effects lower than Aeroxide P25 of the nano-TiO2 powders, probably as a consequence of the presence of acidic moieties at the surface.


Assuntos
Nanopartículas Metálicas/toxicidade , Titânio/toxicidade , Ácido Acético/química , Ácidos Bóricos/química , Brônquios/citologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Glutationa/metabolismo , Humanos , L-Lactato Desidrogenase/metabolismo , Nanopartículas Metálicas/química , Óxido Nítrico/metabolismo , Ácido Oleico/química , Estresse Oxidativo/efeitos dos fármacos , Propriedades de Superfície , Titânio/química , Fator de Necrose Tumoral alfa/metabolismo
14.
Org Biomol Chem ; 14(18): 4304-11, 2016 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-27086654

RESUMO

A convenient, versatile, and green CBS-asymmetric reduction of aryl and heteroaryl ketones has been developed by using the microreactor technology. The study demonstrates that it is possible to handle borane solution safely within microreactors and that the reaction performs well using 2-MeTHF as a greener solvent.

15.
Biochim Biophys Acta ; 1850(2): 385-92, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25459517

RESUMO

BACKGROUND: Selective imaging of lysosomes by fluorescence microscopy using specific fluorescent probes allows the study of biological processes and it is potentially useful also for diagnosis. Lysosomes are involved in numerous physiological processes, such as bone and tissue remodeling, plasma membrane repair, and cholesterol homeostasis, along with cell death and cell signaling. Despite the great number of dyes available today on the market, the search for new fluorescent dyes easily up-taken by cells, biocompatible and bearing bright and long-lasting fluorescence is still a priority. METHODS: Two thiophene-based fluorescent dyes, TC1 and TC2, were synthetized as lysosome-specific probes. RESULTS: The new dyes showed high selectivity for fluorescent staining and imaging of lysosomes and disclosed high photostability, low toxicity and pH insensitivity in the range 2-10. CONCLUSIONS: The TC dyes exhibited high co-localization coefficients (>95%) and moderate quantum yields. They showed high biocompatibility and long-term retention, important features for biological applications. GENERAL SIGNIFICANCE: The results of the present work disclose a new class of organic dyes with potential wide applications as specific and efficient lysosome probes in the study of various biological processes.


Assuntos
Corantes Fluorescentes , Tiofenos , Células 3T3 , Animais , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Lisossomos , Camundongos , Tiofenos/síntese química , Tiofenos/química , Tiofenos/farmacologia
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