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Research Project
Strategic Project - UI 100 - 2013-2014
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Publications
Use of organomolybdenum compounds for promoted hydrolysis of phosphoester bonds in aqueous media
Publication . Gamelas ou Carla A. Gamelas, Carla; Gomes, Ana C.; Fernandes, José A.; Paz, Filipe A. Almeida; Nunes, Patrique; Pillinger, Martyn; Gonçalves, Isabel S.; Romão, Carlos C.; Abrantes, Marta
Application of an Indenyl Molybdenum Dicarbonyl Complex in the Isomerisation of α-Pinene Oxide to Campholenic Aldehyde
Publication . Bruno, S.; Gomes, A. C.; Gamelas ou Carla A. Gamelas, Carla; Abrantes, M.; Oliveira, M. C.; Valente, A.; Almeida-Paz, Filipe; Pillinger, M.; Romão, C.; Gonçalves, I.
The complex [{(Z5-Ind)Mo(CO)2(m-Cl)}2] (1) has been tested for the industrially relevant catalytic isomerisation
of a-pinene oxide (PinOx) to campholenic aldehyde (CPA) in the liquid phase. PinOx conversion and CPA
selectivity are strongly influenced by the solvent employed. Complete conversion of PinOx was achieved
within 1 min at 55 1C or 30 min at 35 1C using 1,2-dichloroethane as solvent, giving CPA in 68% yield.
Other products included trans-carveol, iso-pinocamphone and trans-pinocarveol. The stability of 1 under
the reaction conditions used was investigated by using FT-IR spectroscopy and electrospray ionisation
mass spectrometry (ESI-MS) to characterise recovered solids. In the presence of air/moisture 1 undergoes
oxidative decarbonylation upon dissolution to give oxomolybdenum species that are proposed to include
a tetranuclear oxomolybdenum(V) complex. Conversely, ESI-MS studies of 1 dissolved in dry acetonitrile
show mononuclear species of the type [IndMo(CO)2(CH3CN)n]+. The crystal structure of the ring-slipped
dicarbonyl complex [(Z3-Ind)Mo(CO)2Cl(CH3CN)2] (2) (obtained after dissolution of 1 in acetonitrile) is
reported.
Assessment of a Large-Scale Unbiased Malignant Pleural Effusion Proteomics Study of a Real-Life Cohort
Publication . Zahedi, S; Carvalho, AS; Ejtehadifar, M; Beck, HC; Rei, N; Luís, A; Borralho, P; Bugalho, A; Matthiesen, R
Background: Pleural effusion (PE) is common in advanced-stage lung cancer patients
and is related to poor prognosis. Identification of cancer cells is the standard method for the
diagnosis of a malignant PE (MPE). However, it only has moderate sensitivity. Thus, more sensitive
diagnostic tools are urgently needed. Methods: The present study aimed to discover potential protein
targets to distinguish malignant pleural effusion (MPE) from other non-malignant pathologies. We
have collected PE from 97 patients to explore PE proteomes by applying state-of-the-art liquid
chromatography-mass spectrometry (LC-MS) to identify potential biomarkers that correlate with
immunohistochemistry assessment of tumor biopsy or with survival data. Functional analyses
were performed to elucidate functional differences in PE proteins in malignant and benign samples.
Results were integrated into a clinical risk prediction model to identify likely malignant cases.
Sensitivity, specificity, and negative predictive value were calculated. Results: In total, 1689 individual
proteins were identified by MS-based proteomics analysis of the 97 PE samples, of which 35 were
diagnosed as malignant. A comparison between MPE and benign PE (BPE) identified 58 differential
regulated proteins after correction of the p-values for multiple testing. Furthermore, functional
analysis revealed an up-regulation of matrix intermediate filaments and cellular movement-related
proteins. Additionally, gene ontology analysis identified the involvement of metabolic pathways
such as glycolysis/gluconeogenesis, pyruvate metabolism and cysteine and methionine metabolism.
Conclusion: This study demonstrated a partial least squares regression model with an area under the
curve of 98 and an accuracy of 0.92 when evaluated on the holdout test data set. Furthermore, highly
significant survival markers were identified (e.g., PSME1 with a log-rank of 1.68 × 10−6
).
Use of organomolybdenum compounds for promoted hydrolysis of phosphoester bonds in aqueous media
Publication . Gomes, A.; Gamelas ou Carla A. Gamelas, Carla; Fernandes, J.; Almeida-Paz, F.; Nunes, P.; Pillinger, M.; Gonçalves, I.; Romão, C.; Abrantes, M.
The dissolution of the indenyl (Ind) complex [{(η5‐Ind)Mo(CO)2(μ‐Cl)}2] (1) in N,N′‐dimethylformamide (DMF) gives the ring‐slipped complex [(η3‐Ind)Mo(CO)2Cl(DMF)2] (2). The aerial oxidation of 2 leads to the formation of the dinuclear oxomolybdenum(V) chloride [Mo2O2(DMF)4(μ‐O)2Cl2] (3). The structures of 2 and 3·DMF have been determined by single‐crystal X‐ray diffraction. Compounds 1 and 3 were examined as promoters of phosphoester bond hydrolysis in para‐nitrophenylphosphate (pNPP), which was used as a model substrate. The reactions were performed in aqueous solution at 55 °C and followed by 1H NMR spectroscopy. For assays performed with 30–100 mol‐% of 1 or 3 relative to pNPP, both compounds promote the production of para‐nitrophenol (pNPh) from pNPP. Compound 3 is especially active in promoting the hydrolytic cleavage of the phosphoester bond (t1/2 < 80 min).
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Funders
Funding agency
Fundação para a Ciência e a Tecnologia
Funding programme
6817 - DCRRNI ID
Funding Award Number
PEst-OE/QUI/UI0100/2013