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- 1,6-Conjugate Additions of Carbon Nucleophiles to 2-[(1E,3E)-4-Arylbuta-1,3-dien-1-yl]-4H-chromen-4-onesPublication . Albuquerque, Hélio; Santos, Clementina M.M.; Balanay, Mannix P.; Cavaleiro, José; Silva, ArturKGaA, Weinheim The 1,6-conjugate addition of nitromethane to 2-[(1E,3E)-4-arylbuta-1,3-dien-1-yl]-4H-chromen-4-ones was accomplished and led mainly to the corresponding β-(nitromethyl)chromones. (E)-5′-(Nitromethyl)-3′-styryl-[1,1′-biphenyl] -2-ol and 3′-aryl-2′-nitro-5′-(nitromethyl)spiro[chromane-2,1′-cyclohexan]-4-one derivatives were also isolated as minor products from tandem processes, which result from the addition of a second molecule of nitromethane. The nucleophile scope was investigated with malononitrile, acetylacetone, ethyl cyanoacetate, and diethyl malonate, which gave the expected 1,6-addition products; in the last case, it was also possible to isolate a minor product formed through a 1,8-/1,6-addition sequence. Computational calculations provided a rationale for the experimental reactivity of carbon nucleophiles with 2-[(1E,3E)-4-arylbuta-1,3-dien-1-yl] -4H-chromen-4-ones. The further functionalization of some adducts allowed the preparation of new nitrogen-containing heterocyclic compounds, such as new styrylpyrrolidines and new pyrazole and bis(pyrazole) derivatives.
- 1-aryl-3-(4-(7-methylthieno[3,2-d]pyrimidin-4-yloxy)phenyl)ureas: synthesis and molecular modelling studies using VEGFR-2Publication . Soares, Pedro; Froufe, Hugo J.C.; Abreu, Rui M.V.; Ferreira, Isabel C.F.R.; Borges, Fernanda; Queiroz, Maria João R.P.The development of anticancer drugs inhibiting angiogenesis has been an area of extensive research in the past decade. Angiogenesis is a requirement for tumor growth and metastasis and occurs through several signalling pathways. One key pathway that initiates proliferation and migration of endothelial cells is signalling through the vascular endothelial growth factor receptor-2 (VEGFR-2).1 Therefore, small molecules that block this signalling pathway through inhibition of VEGFR-2 tyrosine kinase activity could potentially inhibit angiogenesis and tumor growth. Recently works describing thienopyrimidine2 and thienopyrimidine 1,3-diarylureas3 as VEGFR-2 inhibitors have emerged in the literature. Here we present the synthesis of new 1-aryl-3-(4-(7-methylthieno[3,2-d]pyrimidin-4-yloxy)phenyl)ureas 2 in high yields by reaction of 4-[(7-methylthieno[3,2-d]pyridin-4-yl)oxy]aniline 1 with arylisocyanates. The former was prepared by regioselective nucleophilic substitution of 4-chloro-7-methylthieno[3,2-d]pyrimidine with 4-aminophenol
- 1-Aryl-3-[ 4-( thieno[3,2-d]pyrimidin-4-yloxy )phenyl]ureas as VEG FR2 inhibitors: synthesis, docking enzymatic and cellular assaysPublication . Peixoto, Daniela; Calhelha, Ricardo C.; Soares, Pedro; Abreu, Rui M.V.; Froufe, Hugo J.C.; Ferreira, Isabel C.F.R.; Costa, Raquel; Soares, Raquel; Queiroz, Maria João R.P.A number of thienopyrimidines derivatives have shown potent VEGFR2 (Vascular Endothelium Growth Factor Receptor2) tyrosine kinase inhibition activity.[ll VEGF is a sun·ogate marker of angiogenesis that activates VEGFR2 in endothelial cells. Here we present the synthesis of new 1-aryl-3-[ 4-(thieno[3,2-d]pyrimidin-4- yloxy)phenyl]ureas from the aminodi(hetero)arylether 1, also prepared by us, which was reacted with arylisocyanates to give the corresponding 1,3-diarylureas 2a-c.
- 1-Aryl-3-[4-(thieno[3,2-d]pyrimidin-4-yloxy)phenyl]ureas as potential inhibitors of VEGFR-2: synthesis and molecular modelling studiesPublication . Soares, Pedro; Froufe, Hugo J.C.; Abreu, Rui M.V.; Ferreira, Isabel C.F.R.; Borges, Fernanda; Queiroz, Maria João R.P.Angiogenesis is a requirement for tumor growth and metastasis and occurs through several signalling pathways. One key pathway that initiates proliferation and migration of endothelial cells is signalling through the vascular endothelial growth factor receptor-2 (VEGFR-2).1 Therefore, small molecules that block this signalling pathway through inhibition of the VEGFR tyrosine kinase activity could potentially inhibit angiogenesis and tumour growth. Recently works describing thienopyrimidines2 and thienopyridine ureas3 as inhibitors of VEGFR-2 have appeared in the literature. Here we present the synthesis of new 1,3-diarylureas 2 starting by regioselective nucleophilic substitution of the 4-chlorothieno[3,2-d]pyrimidine with 4-aminophenol to obtain 4-(thieno[3,2-d]pyridin-4-yloxy)aniline 1 which reacts with different arylisocyanates
- 1-Aryl-3-[4-(thieno[3,2-d]pyrimidin-4-yloxy)phenyl]ureas as VEGFR-2 tyrosine kinase inhibitors: Synthesis, biological evaluation, and molecular modelling studiesPublication . Soares, Pedro; Costa, Raquel; Froufe, Hugo J.C.; Calhelha, Ricardo C.; Peixoto, Daniela; Abreu, Rui M.V.; Ferreira, Isabel C.F.R.; Soares, Raquel; Queiroz, Maria João R.P.The Vascular Endothelial Growth Factor Receptor-2 (VEGFR-2) is a tyrosine kinase receptor involved in the growth and differentiation of endothelial cells that is implicated in tumor-associated angiogenesis. In this study novel 1-aryl-3-[4-(thieno[3,2-d]pyrimidin-4-yloxy)phenyl]ureas were synthesized and evaluated for the VEGFR-2 tyrosine kinase inhibition. Three of these compounds showed good VEGFR-2 inhibition presenting low IC50 values (150-199 nM) in enzymatic assays. The latter promoted also significant inhibition of cell proliferation at low concentrations (0.5-1 µM), not affecting cell viability, of VEGF-stimulated Human Umbilical Vein Endothelial Cells (HUVECs) using the BrdU assay. The determination of the total and phosphorylated (active) VEGFR-2 was performed by western-blot, and it was possible to conclude that the compounds significantly inhibit the phosphorylation of the receptor at 1 µM pointing to their antiproliferative mechanism of action in HUVECs. The molecular rationale for inhibiting the tyrosine kinase domain of VEGFR-2 was also done and discussed using molecular docking studies.
- 1-Aryl-3-[4-(thieno[3,2-d]pyrimidin-4-yloxy)phenyl]ureas as VEGFR2 tyrosine kinase inhibitors: synthesis, docking studies, enzymatic and cellular assaysPublication . Queiroz, Maria João R.P.; Peixoto, Daniela; Soares, Pedro; Abreu, Rui M.V.; Froufe, Hugo J.C.; Calhelha, Ricardo C.; Ferreira, Isabel C.F.R.; Costa, Raquel; Soares, RaquelA number of thienopyrimidines derivatives have shown potent vascular endothelial growth factor receptor 2 (VEGFR2) inhibition activity. Here, we present the synthesis of new 1-aryl-3-[4-(thieno[3,2-d) pyrimidin-4-yloxy)phenyl]ureas by promoting t he regioselective attack of the hydroxy group of the 4-aminophenol in the chlorine nucleophilic displacement on two 4-chlorinated thieno[3,2-d]pyrimidines, obtaining compounds la and 1b which were reacted with arylisocyanates to give t he corresponding 1,3-diarylureas 2a-f (see scheme). These compounds were evaluated for inhibition of VEGFR2 tyrosine kinase activity using enzymatic assays, and 2a- c showed good inhibition ability with IC50 values in the range of hundreds of nanomolar. The rationale for the inhibition activity is also discussed using docking. To examine the activity of 2a- c in endothelial cells, human umbilical vein endothelial cells (HUVECs) were cultured in the presence or absence of each compound in different concentrations. A decrease in the proliferation of HUVECs was observed by the incorporation of BrdU quantified by ELISA assay. Given the established role of VEGFR2 in proliferation and migration of endothelial cells, these molecules are promising antiangiogenic agents that can be used for therapeutic purposes in pathological conditions where angiogenesis is exacerbated, such as cancer.
- 10º Encontro Nacional de Cromatografia: livro de resumosPublication . Peres, António M. (Ed.); Barros, Lillian (Ed.); Dias, L.G. (Ed.); Ferreira, Isabel C.F.R. (Ed.)Este livro contém os resumos de todas as comunicações apresentadas no 10º Encontro Nacional de Cromatografia, realizado no Instituto Politécnico de Bragança, de 4 a 6 de Dezembro de 2017
- 11th International Conference on Predictive Modelling in Food: book of abstractsPublication . Gonzales-Barron, Ursula (Ed.); Cadavez, Vasco (Ed.)It is our great pleasure to welcome you in Bragança, Portugal, for the 11th International Conference of Predictive Modelling in Food (ICPMF11). Since 1992, ten ICPMF editions have taken place, providing a forum for the exchange of ideas, identification of research needs and novel approaches for the advancement of predictive modelling towards ensuring safety and quality of foods. Bragança is a typically-Portuguese old town (Romanic origin dates back to the 10th century), located by the Natural Park of Montesinho – one of the wildest forest zones of Europe – and the Douro Valley – the third oldest protected wine region in the world; and surrounded by traditional villages of a distinctive rustic beauty. Bragança houses several traditional industries producing a myriad of local foods, such as cheese, fermented meats, wine, chestnuts and honey, which provide substantial economic sustainability to the region. ICPMF11 reunites food researchers, stakeholders, risk assessors and users of predictive models to present recent developments and trends in modelling approaches for food quality, safety and sustainability. We succeeded to gather a significant number of delegates from over the world to participate in a comprehensive scientific programme that includes keynote lectures, oral communications and posters, allocated in sessions focusing on: . Advances in predictive microbiology modelling . Predictive modelling in innovative food processing and preservation technologies . Advances in microbial dynamics and interactions . Advances in software and database tools . Meta-analysis protocols and applications . Advances in risk assessment methods and integration of omics techniques . Advances in predictive modelling in food quality and safety . Predictive mycology . Individual cell and whole-cell modelling Apart from those, ICPMF11 features for the first time a special session dedicated to “Innovative approaches for ensuring safety of traditional foods” and the Round Table: “Assuring the Safety of Traditional Foods: A Scientific Contribution to Protecting our Cultural Heritage”. We, as food researchers based in a Mediterranean mountain region, are aware that the production of traditional foods plays a key role in the development of rural regions, since the agricultural commodities used as raw materials are generally produced locally, allowing and stimulating local commercialisation, thus contributing to a sustainable environment, and employment in rural populations. It was inspiring for us to have received many submissions from both developed and developing countries on the valorisation of traditional foods through the application of up-to-date modelling research. Besides that, one morning workshop and three afternoon tutorials were programmed during the day before the scientific programme. The workshop “How to benefit from the Risk Assessment Modelling and Knowledge Integration Platform (RAKIP)” was organised by Matthias Filter. The parallel tutorials “Towards an integrated predictive software map: Practical examples of use of predictive microbiology software tools for food safety and quality”; “Advanced methods in predictive microbiology” and “Topics in quantitative microbial risk assessment using R” were organised by Fernando Pérez-Rodríguez, Pablo Fernández, Alberto Garre and Mariem Ellouze; by Lihan Huang, Cheng-An Hwang and Vasco Cadavez; and by Patrick Njage and Ana Sofia Ribeiro Duarte, respectively. We thank these organisers for their proposals. Abstracts, reviewed by the ICPMF11 Scientific Committee, are published in the present Book of Abstracts while peer-reviewed original research articles will be invited to be published in ICPMF11 Special Issues in the International Journal of Food Microbiology and Microbial Risk Analysis. To stimulate the participation of postgraduate students and young researchers, two kinds of awards were arranged: the Young Researcher Best Oral Presentation prizes, sponsored by Elsevier; and the Developing Scientist Best Poster prizes, sponsored by the International Committee on Food Microbiology and Hygiene (ICFMH) of the International Union of Microbiological Societies (IUMS). For the first time, this ICPMF edition gives out two awards for the Senior Researcher Best Oral Presentation, sponsored by the open-access journal Foods – MDPI. In addition to the scientific programme, we prepared an exciting social programme for delegates to appreciate the rich culture, gastronomy and traditions of Bragança, w includes welcome reception, live music, tasting of regional food and a gala dinner in the Castle of Bragança. We look forward to lively discussions, and hope that this meeting will give you the opportunity to strengthen friendship and cooperation, and build new contacts for future research endeavours.
- 15 anos de estudo da mosca-da-azeitona, Bactrocera oleae Gmel., no Nordeste de Portugal.Publication . Bento, Albino; Pereira, J.A.A mosca-da-azeitona, Bactrocera oleae (Omel.) e considerada praga chave da oliveira nos países da Bacia do Mediterrâneo, variando a importância dos prejuízos causados pelo insecto consideravelmente entre anos e locais em fun9ao das condi90es climáticas e das políticas agronómicas.
- 17 α-Ethinylestradiol degradation in continuous process by photocatalysis using Ag/Nb2O5 immobilized in biopolymer as catalystPublication . Lenzi, Giane G.; Abreu, Eduardo; Fuziki, Maria Eduarda K.; Fidelis, Michel Zampieri; Brackmann, Rodrigo; Díaz de Tuesta, Jose Luis; Gomes, Helder; Santos, Onélia A.A. dosThis study describes the application of Ag/Nb2O5 catalysts, suspension and spheres alginate immobilized for the degradation of 17α-Ethinylestradiol (EE2). The techniques used to characterize the photocatalysts were as follows: X-ray diffraction (XRD), N2 adsorption–desorption analysis (BET), point charge zero charge (PZC), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Different catalyst calcination temperatures were studied by keeping the silver metal loading at 5%. Among the operational conditions analyzed were pH, catalyst concentration, the emitting source of radiation and the inlet flow rate (in continuous operation). The results of the experiments performed initially with the catalyst in suspension revealed that the highest catalytic activity in the degradation of EE2 was the 5%Ag/Nb2O5 catalyst calcined at 973 K, which removed 77.7% of the initial pollutant concentration in 120 min of reaction. The immobilization of the catalyst in alginate spheres resulted in a degradation reduction, being able to degrade 69.2% of the initial EE2 in a batch system. In the continuous system, the immobilized catalyst obtained a total degraded of 37.3%, with a flow rate of 10 L·h−1. Catalyst reuse was promising, even dropping the removal, degrading around 27% of the initial EE2 concentration in the third cycle of use.