Title: A nickel glutamate metal biomolecule framework
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Utilizando a expertise acumulada ao longo de muitos anos, o LaMuCrEs possui múltiplos interesses e linhas de pesquisa, como Mineralogia, Insumos farmacêuticos e Compostos de Coordenação.
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Abstract: Cancer resistance to chemotherapeutic agents such as cisplatin presents a significant challenge, leading to treatment failure and poor outcomes. Novel metal-based compounds offer a promising strategy to overcome drug resistance and to enhance efficacy. Four Ru(II) complexes with fenamic acid derivatives were synthesized and characterized: [Ru(L)(bipy)(dppp)]PF6, where L represents fenamic acid (HFen, complex 1), mefenamic acid (HMFen, complex 2), tolfenamic acid (HTFen, complex 3), and flufenamic acid (HFFen, complex 4). Their composition was supported by molar conductivity, elemental analysis, Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, mass spectrometry, and 31P{1H}, 1H, and 13C nuclear magnetic resonance, with the crystal structure of complex 1 confirmed via X-ray diffraction. Complexes 1-4 exhibited notable cytotoxicity against tested cell lines, particularly A2780 and A2780cisR (cisplatin-resistant ovarian tumors), compared to MDA-MB-231 (breast) and A549 (lung) lines. Mechanistic studies revealed weak DNA interactions through minor grooves or electrostatic binding. Cellular uptake assays showed effective internalization of complexes 1 (3.6%) and 2 (4.5%), correlating with potent IC50 values. These complexes also altered cell morphology, reduced cell density, and inhibited colony formation in the A2780 cells. Staining assays indicated induced cell death and organelle damage, highlighting their potential as promising antitumor agents.
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Abstract: Hydrochlorothiazide (HTZ) is a thiazide-type diuretic drug approved by the FDA in 1959 for treatment of hypertension and peripheral edema and has been used since. HTZ exhibits low solubility and low permeability, leading to variable oral bioavailability and limited intestinal drug permeability. For this reason, several attempts to improve HTZ physicochemical properties have been made during the past decades. In the broad frame of molecular crystal engineering, significant efforts and promising results in the quest for more effective solid/dosage forms of HTZ, including studies on polymorphism and cocrystals, are being developed. As part of these efforts, we report here two new cocrystals of HTZ with the zwitterionic L-proline and the prodrug 5-Fluorocytosine. Both cocrystals show improvement in solubility and permeability, suggesting that these new solid forms could be used as new drug candidates to deliver HTZ in the antihypertensive therapy.
Abstract: Leishmaniasis is a neglected disease that affects regions such as South Asia, South Africa, and Latin America, less developed regions. The research proposed the conformational study of brominated guanidine compounds with potential antileishmanial activity using Nuclear Magnetic Resonance (NMR) and X-ray diffraction (XRD) techniques. The present study involves the brominated molecules LQOF-G2, LQOF-G30, LQOF-G35 and LQOF-G35-Br. The latter was synthesized by the reaction of LQOF-G35 with NBS under IR irradiation at 120 Watts of potency and dichloromethane as solvent by 12 h of exposition. The obtained results demonstrated the efficiency of the bromination method, since two bromine atoms entered the molecule. Furthermore, NMR analysis showed a conformational change from Z to E when compound LQOF-G35 was brominated to LQOF-G35-Br. This behavior was confirmed by a comparative XRD study of the LQOF-G35 and LQOF-G35-Br compounds. The antileishmanial activity of LQOF-G2 e LQOF-G35 motivated the synthesis of new brominated compounds LQOF-G30 e LQOF-G35-Br.
Abstract: In recent years, there has been a growing interest in developing advanced materials for photonics applications, particularly for efficient white light emission, which is crucial for technologies like solid-state lighting and display devices. One interesting approach for emitting white light is Upconversion (UC) luminescence. This study focuses on synthesis, by a new and alternative method, and characterization of yttrium ytterbium gallium garnet (Yb-YGG) single crystals, specifically Y1.8Yb1.2Ga5O12, doped with various concentrations of Er3+ and Tm3+ ions. These crystals were studied intending to enhance UC luminescence properties for white light generation by modifying their respective emissions in the red, green, and blue (RGB) regions. Unlike traditional methods such as Czochralski, these crystals were produced by controlled nucleation and growth through gradual cooling of a specific glass mixture, leading to Yb-YGG single crystals doped with different concentrations of Yb3+, Er3+, and Tm3+ ions. By optimizing the Yb3+/Tm3+/Er3+ ratio, the study allowed to obtain micrometric single crystals that efficiently emit white light via UC. The crystals were characterized by X-ray diffraction, optical and electronic microscopies, EDS and luminescence spectroscopy.
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Abstract: Ciprofibrate (CIP) is an active pharmaceutical ingredient (API) classified as class II on the basis of biopharmaceutical classification system (BCS), what indicates that it has low solubility in aqueous solvents. The use of API salts has attracted attention due to their improvements in solubility, tolerability, higher rate and extent of absorption, and faster onset of the therapeutic effect. In this work, a new crystalline CIP monohydrated calcium salt (Ca(CIP)2.H2O) was successfully obtained and its crystal structure determined by single crystal X-ray diffraction analysis (SCXRD). Additionally, Ca(CIP)2.H2O was widely characterized by powder X-ray diffraction (PXRD), Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and submitted to solubility, intrinsic dissolution and accelerated stability studies. Ca(CIP)2.H2O exhibited higher solubility and dissolution rate than CIP-free form and was stable up to 6 months at 40 °C (75 %RH). Therefore, Ca(CIP)2.H2O may be a viable alternative for use in solid dosage forms.
Abstract: The cocrystallization of active pharmaceutical ingredients (APIs) is known to be a technique suitable for overcoming certain physicochemical issues concerning the solid forms of drugs. In the case of the cocrystal of 5-fluorocytosine and isoniazid, two widely used active pharmaceutical ingredients, for example, the cocrystallization improved the phase stability of the latter against moisture, thus increasing its shelf life. The room-temperature crystal structure was already reported in the literature, but no charge density study has been published so far. To further evaluate the structural properties of this potential codrug, which is stabilized by a supramolecular synthon containing N-H···N-type hydrogen bonds, here we performed the experimental and theoretical charge density analyses of the drug-drug cocrystal formed by the antimetabolite prodrug 5-fluorocytosine and the tuberculostatic drug isoniazid. Topological analyses were also performed for all models and compared, indicating a good agreement between experiment and theory. The comparison with gas-phase calculations enabled the evaluation of the charge redistribution upon cocrystallization as well as the effect of the intermolecular interactions. In this manner, it was possible to evaluate the variations in bond distances and electron densities at the bonds involved in the intermolecular heterosynthon. Through the total charge of each molecule in the cocrystal, it was also possible to have insights into the charge redistribution when both molecules crystallize together. Electrostatic potential maps were also calculated for the experimental data and compared with the gas-phase calculations.
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