Publications by authors named "Consuelo Jimenez"

Despite numerous studies evaluating the antimicrobial activity of essential oil components (EOCs) against different microorganisms, the effect of the composition of the matrix in which they are applied remains unexplored. Hence, the effect of different food components (i.e.

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The construction of triplet-triplet annihilation upconversion (TTA-UC) systems with upconversion (UC) emission efficiency at low power densities is still under continuing exploration. From an environmental point of view, the utilization of purely organic pairs is more beneficial than the involvement of transition-metal complexes. In this context, 4,4-difluoro-4-bora-3a,4a-diaza--indacene (BODIPY) dyes, which can be found in a wide range of applications, have been previously used as suitable sensitizers in TTA-UC systems.

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Photon upconversion based on triplet-triplet annihilation (TTA-UC) is an attractive wavelength conversion with increasing use in organic synthesis in the homogeneous phase; however, this technology has not performed with canonical solid catalysts yet. Herein, a BOPHY dye covalently anchored on silica is successfully used as a sensitizer in a TTA system that efficiently catalyzes Mizoroki-Heck coupling reactions. This procedure has enabled the implementation of in-flow reaction conditions for the synthesis of a variety of aromatic compounds, and mechanistic proof has been obtained by means of transient absorption spectroscopy.

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The in situ generation of active photoredox organic catalysts upon anion-binding co-catalysis by making use of the ionic nature of common photosensitizers is reported. Hence, the merge of anion-binding and photocatalysis permitted the modulation of the photocatalytic activity of simple acridinium halide salts, building an effective anion-binding - photoredox ion pair complex able to promote a variety of visible light driven transformations, such as anti-Markovnikov addition to olefins, Diels-Alder and the desilylative C-C bond forming reactions. Anion-binding studies, together with steady-state and time-resolved spectroscopy analysis, supported the postulated ion pair formation between the thiourea hydrogen-bond donor organocatalyst and the acridinium salt, which proved essential for unlocking the photocatalytic activity of the photosensitizer.

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Talazoparib (TLZ) is a poly(adenosine diphosphate [ADP]-ribose) polymerase inhibitor employed for the treatment of breast cancer. This drug displays an absorption band in the UVA region, and therefore investigation of the possible phototoxic side-effects associated to its administration results of enormous relevance. In this context, we describe here a photochemical and photobiological study to ascertain the photosafety profile of TLZ.

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The interaction dynamics between flurbiprofen (FBP) and tryptophan (Trp) has been studied in covalently linked dyads and within human serum albumin (HSA) by means of fluorescence and ultrafast transient absorption spectroscopy. The dyads have proven to be excellent models to investigate photoinduced processes such as energy and/or electron transfer that may occur in proteins and other biological media. Since the relative spatial arrangement of the interacting units may affect the yield and kinetics of the photoinduced processes, two spacers consisting of amino and carboxylic groups separated by a cyclic or a long linear hydrocarbon chain (1 and 2, respectively) have been used to link the ()- or ()-FBP with the ()-Trp moieties.

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The design and development of new triplet-triplet annihilation upconversion (TTA-UC) systems combining triplet sensitizers with acceptor compounds have attracted considerable interest. In this vein, sensitizers made from purely organic dyes rather than transition-metal complexes appear to be more convenient from an environmental point of view. BODIPYs are a very well-known class of dyes with applications in a widespread range of scientific areas.

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A novel dual functional and visual rhodamine ethylenediamine bis(triazolyl silsesquioxane) (RBS) chemosensor was successfully synthesized using "click" chemistry. The results have unambiguously demonstrated that RBS can act in fluorescent and colorimetric sensing of Cu and Zn by their respective coordination with triazole structures and, more importantly, it has also been found that triazole-amide of RBS could turn on chelation-enhanced fluorescence (CHEF) of Cu. Remarkably, the addition of Cu triggered an enhanced fluorescent emission by 63.

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The search for economic alternatives in the use of expensive scientific equipment represents a way of providing many laboratories access to scientific developments that, otherwise, might be hampered by economic constraints. This inspired the purpose of this work, which was to demonstrate for the first time that we can carry out the photoreduction of aryl halides via green-to-blue upconversion in an aerated gel medium, using a simple economic set-up based on easily accessible and low-cost laser pointers. The optimized set-up consists of three laser pointers connected to a switching-mode power supply.

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A novel visible light promoted formation of C S bonds through electron donor-acceptor (EDA) complexes of alkylamines with 5- and 6-membered (hetero)arene halides is presented. This represents the first EDA-based thiolation method not relying on π-π or a thiolate-anion-π interactions and provides a facile access to heteroarene radicals, which can be suitably trapped by disulfide derivatives to form the corresponding versatile arylsulfides. Mechanistic investigations on the aspects of the whole process were conducted by spectroscopic measurements, demonstrating the hypothesized EDA complex formation.

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In this work, the feasibility of triplet fusion upconversion (TFU, also named triplet-triplet annihilation upconversion) technology for the functionalization (arylation) of furans and thiophenes has been successfully proven. Activation of aryl halides by TFU leads to generation of aryl radical intermediates; trapping of the latter by the corresponding heteroarenes, which act as nucleophiles, affords the final coupling products. Advantages of this photoredox catalytic method include the use of very mild conditions (visible light, standard conditions), employment of commercially available reactants and low-loading metal-free photocatalysts, absence of any sacrificial agent (additive) in the medium and short irradiation times.

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A new strategy to achieve efficient aerobic phosphorylation of five-membered heteraroenes with excellent yields using dichromatic photoredox catalysis in a gel-based nanoreactor is described here. The procedure involves visible aerobic irradiation (cold white LEDs) of a mixture containing the heteroarene halide, trisubstituted phospite, ,-diisopropylethylamine (DIPEA) as sacrificial agent, and catalytic amounts of 9,10-dicyanoanthracene () in the presence of an adequate gelator, which permits a faster process than at the homogeneous phase. The methodology, which operates by a consecutive photoinduced electron transfer (ConPET) mechanism, has been successfully applied to the straightforward and clean synthesis of a number of different heteroarene (furan, thiophene, selenophene, pyrrole, oxazole, or thioxazole) phosphonates, extending to the late-stage phosphonylation of the anticoagulant rivaroxaban.

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Heteroarene boronate esters constitute valuable intermediates in modern organic synthesis. As building blocks, they can be further applied to the synthesis of new materials, since they can be easily transformed into any other functional group. Efforts toward novel and efficient strategies for their preparation are clearly desirable.

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Cisplatin is one of the most widely used chemotherapeutic agents in oncology, although its nephrotoxicity limits application and dosage. We present the results of a clinical study on prophylaxis of cisplatin-induced nephrotoxicity in patients with peritoneal carcinomatosis undergoing cytoreduction and hyperthermic intraperitoneal intraoperative chemotherapy (HIPEC-cisplatin). Prophylaxis was with imipenem/cilastatin.

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The recent demand for fluorescent-labeled materials (FLMs) in forensic security concepts such as latent fingerprints (LFs) that encode information for anti-counterfeiting and encryption of confidential data makes necessary the development of building new and innovative materials. Here, novel FLMs based on polyhedral oligomeric silsesquioxanes (POSS) functionalized with fluorophores via "click" reactions have been successfully synthesized and fully characterized. A comprehensive study of their photophysical properties has displayed large Stokes's shift together with good photostability in all cases, fulfilling the fundamental requisites for any legible LF detection on various surfaces.

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Boron-containing thiophenes are important entities in organic/medicinal chemistry as well as in material science. In this Letter, a novel, straightforward, and fast procedure for their production employing visible light as an energy source at room temperature and ambient pressure is reported. All substrates are commercially available, and the process does not require the use of any external photocatalyst.

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Intraoperative factors implicated in postoperative mortality after liver transplantation (LT) are poorly understood. Because LT is a particularly demanding procedure, we hypothesized that intraoperative myocardial injury may be frequent and independently associated with early postoperative outcomes. We aimed to determine the association between intraoperative high-sensitivity troponin (hsTn) elevation during LT and 30-day postoperative mortality.

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Four new dyes that derive from borylated arylisoquinolines were prepared, containing a third aryl residue (naphthyl, 4-methoxynaphthyl, pyrenyl or anthryl) that is linked via an additional stereogenic axis. The triaryl cores were synthesized by Suzuki couplings and then transformed into boronic acid esters by employing an Ir(I)-catalyzed reaction. The chromophores show dual emission behavior, where the long-wavelength emission band can reach maxima close to 600 nm in polar solvents.

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In this work, a molecular hydrogel made of gelator (S)-4-((3-methyl-1-(nonylamino)-1-oxobutan-2-yl)amino)-4-oxobutanoic acid (SVN) has been employed as soft container to modify the photochemical and photophysical behavior of the antipsychotic drug cyamemazine (CMZ). The interaction of CMZ with the gel network has been evidenced by fluorescence spectroscopy through a hypsochromic shift of the emission band (from λ = 521 nm in solution to λ = 511 nm in the gel) and an increase of the fluorescence lifetime (5.6 ns in PBS vs.

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Transient absorption spectroscopy in combination with in silico methods has been employed to study the interactions between human serum albumin (HSA) and the anti-psychotic agent chlorpromazine (CPZ) as well as its two demethylated metabolites (MCPZ and DCPZ). Thus, solutions containing CPZ, MCPZ or DCPZ and HSA (molar ligand:protein ratios between 1:0 and 1:3) were submitted to laser flash photolysis and the ΔA value at λ = 470 nm, corresponding to the triplet excited state, was monitored. In all cases, the protein-bound ligand exhibited higher ΔAmax values measured after the laser pulse and were also considerably longer-lived than the non-complexed forms.

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Triflusal is a platelet antiaggregant employed for the treatment and prevention of thromboembolic diseases. After administration, it is biotransformed into its active metabolite, the 2-hydroxy-4-trifluoromethylbenzoic acid (HTB). We present here an investigation on HTB photobinding to human serum albumin (HSA), the most abundant protein in plasma, using an approach that combines fluorescence, MS/MS, and peptide fingerprint analysis as well as theoretical calculations (docking and molecular dynamics simulation studies).

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Latent electrophiles are nowadays very attractive chemical entities for drug discovery, as they are unreactive unless activated upon binding with the specific target. In this work, the utility of 4-trifluoromethyl phenols as precursors of latent electrophiles, quinone methides (QM), for lysine-targeting is demonstrated. These Michael acceptors were photogenerated for specific covalent modification of lysine residues using human serum albumin (HSA) as a model target.

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Binding of the immunosuppressive agent mycophenolate mofetil (MMP) and its pharmacologically active metabolite mycophenolic acid (MPA) to human serum albumin (HSA) and α-acid glycoprotein (HAAG) has been investigated by means of an integrated approach involving selective excitation of the drug fluorophore, following their UV-A triggered fluorescence and docking studies. The formation of the protein/ligand complexes was evidenced by a dramatic enhancement of the fluorescence intensity and a hypsochromic shift of the emission band. In HSA, competitive studies using oleic acid as site I probe revealed site I as the main binding site of the ligands.

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Diclofenac (DCF) can cause adverse reactions such as gastrointestinal, renal and cardiovascular disorders; therefore, topical administration may be an attractive alternative to the management of local pain in order to avoid these side effects. However, previous studies have shown that DCF, in combination with sunlight, displays capability to induce photosensitivity disorders. In humans, DCF is biotransformed into hydroxylated metabolites at positions 4' and 5 (4'OH-DCF and 5OH-DCF), and this chemical change produces non negligible alterations of the drug chromophore, resulting in a significant modification of its light-absorbing properties.

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The covalent binding of β-lactams to proteins upon photochemical activation has been demonstrated by using an integrated approach that combines photochemical, proteomic and computational studies, selecting human serum albumin (HSA) as a target protein and ezetimibe (1) as a probe. The results have revealed a novel protein haptenation pathway for this family of drugs that is an alternative to the known nucleophilic ring opening of β-lactams by the free amino group of lysine residues. Thus, photochemical ring splitting of the β-lactam ring, following a formal retro-Staudinger reaction, gives a highly reactive ketene intermediate that is trapped by the neighbouring lysine residues, leading to an amide adduct.

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