27 research outputs found
Supramolecular Nature of Multicomponent Crystals Formed from 2, 2'-Thiodiacetic Acid with 2, 6-Diaminopurine or N9-(2-Hydroxyethyl) adenine.
The synthesis and characterization of the multicomponent crystals formed by 2,2′-thiodiacetic acid (H2tda) and 2,6-diaminopurine (Hdap) or N9-(2-hydroxyethyl)adenine (9heade) are detailed in this report. These crystals exist in a salt rather than a co-crystal form, as confirmed by single crystal X-ray diffractometry, which reflects their ionic nature. This analysis confirmed proton transfer from the 2,2′-thiodiacetic acid to the basic groups of the coformers. The new multicomponent crystals have molecular formulas [(H9heade+)(Htda−)] 1 and [(H2dap+)2(tda2−)]·2H2O 2. These were also characterized using FTIR, 1H and 13C NMR and mass spectroscopies, elemental analysis, and thermogravimetric/differential scanning calorimetry (TG/DSC) analyses. In the crystal packing the ions interact with each other via O–H⋯N, O–H⋯O, N–H⋯O, and N–H⋯N hydrogen bonds, generating cyclic hydrogen-bonded motifs with graph-set notation of ��22 (16), ��22 (10), ��23 (10), ��33 (10), ��22 (9), ��23 (8), and ��24
(8), to form different supramolecular homo- and hetero-synthons. In addition, in the crystal packing of 2, pairs of diaminopurinium ions display a strong anti-parallel π,π-stacking interaction, characterized by short inter-centroids and interplanar distances (3.39 and 3.24 Å, respectively) and a fairly tight angle (17.5°). These assemblies were further analyzed energetically using DFT calculations, MEP surface analysis, and QTAIM characterization
Degradación del 4,5-diamino-2,6-dioxo-3-metil-1,2,3,6-tetrahidropirimidina en disolución acuosa
Se ha estudiado la cinética del proceso de degradación del 4,5-diamino-2,6-dioxo-3-metil-1,2,3,6-tetrahidropirimidina en disolución acuosa. El producto final del proceso de degradación se ha caracterizado mediante análisis químico, espectrofotometría de masas, IR y RMN, sugiriendo se para el, la fórmula correspondiente al 1 ,6-dimetil-2,4, 7 ,9-tetrahidroxipirimidina4,5, h-pteridina.The cinetic of the degradation process of the 4,5-diamine-2,6-dioxo-3-methyl1,2,3,6-tetrahidropyrimidine has been studied in aqueous solution. The fmal product of the degradation process has been characterized by means of chemical analysis, espectrofotometry of mass, IR, NMR, suggests that tite formula corresponds
to 1 ,6-dimethyl-2,4, 7 ,9-tetrahidroxypyrimido4,5, h pteridine
Novel Cd (II) Coordination Polymers Afforded with EDTA or Trans-1,2-Cdta Chelators and Imidazole, Adenine, or 9-(2-Hydroxyethyl) Adenine Coligands
We thank the “Centre de Tecnologies de la Informació” (CTI), Universitat de les Illes Balears
for computational facilities. We also thank all Projects for financial support.Three mixed-ligands of Cd(II) coordination polymers were unintentionally obtained:
{[Cd(µ3-EDTA)(Him)·Cd(Him)(H2O)2]·H2O}n (1), {[Cd(µ4-CDTA)(Hade)·Cd(Hade)2]}n (2), and
{[Cd(µ3-EDTA)(H2O)·Cd(H9heade)(H2O)]·2H2O}n (3), having imidazole (Him), adenine (Hade)
or 9-(2-hydroxyethyl)adenine (9heade) as the N-heterocyclic coligands. Compounds 2 and 3 were
obtained by working with an excess of corresponding N-heterocyclic coligands. The single-crystal
X-ray diffraction structures and thermogravimetric analyses are reported. The chelate moieties in
all three compounds exhibit hepta-coordinated Cd centers, whereas the non-chelated Cd center is
five-coordinated in 1 and six-coordinated in 2 and 3. Him and Hade take part in the seven-coordinated
chelate moieties in 1 and 2, respectively. In contrast, 9heade is unable to replace the aqua ligand
of the chelate [Cd (EDTA) (H2O)] moiety in 3. The thermogravimetric analysis (TGA) behavior of
[Cd (H2EDTA) (H2O)]·2H2O in 1 and 3 leads to a residue of CdO, whereas the N-rich compound
2 yields CdO·Cd(NO3)2 as a residue. Density functional theory (DFT) calculations along with
molecular electrostatic potential (MEP) and quantum theory of atoms-in-molecules computations
were performed in adenine (compound 2) and (2-hydroxyethyl)adenine (compound 3) to analyze
how the strength of the H-bonding and π-stacking interactions, respectively, are affected by their
coordination to the Cd-metal center.Excellence Network "Metal Ions in Biological Systems" MetalBio
CTQ2017-90802-REDTJunta de Andalucia
FQM-283MICIU /AEI of Spain
CTQ2017-85821-
Anion–Cation Recognition Pattern, Thermal Stability and DFT-Calculations in the Crystal Structure of H2dap[Cd(HEDTA)(H2O)] Salt (H2dap = H2(N3,N7)-2,6-Diaminopurinium Cation)
We thank the Centre de Tecnologies de la Informació (CTI), Universitat de les Illes Balears for
computational facilities. We also thank all projects for financial support.The proton transfer between equimolar amounts of [Cd(H2EDTA)(H2O)] and
2,6-diaminopurine (Hdap) yielded crystals of the out-of-sphere metal complex H2(N3,N7)dap
[Cd(HEDTA)(H2O)]·H2O (1) that was studied by single-crystal X-ray diffraction, thermogravimetry,
FT-IR spectroscopy, density functional theory (DFT) and quantum theory of “atoms-in-molecules”
(QTAIM) methods. The crystal was mainly dominated by H-bonds, favored by the observed tautomer
of the 2,6-diaminopurinium(1+) cation. Each chelate anion was H-bonded to three neighboring
cations; two of them were also connected by a symmetry-related anti-parallel π,π-staking interaction.
Our results are in clear contrast with that previously reported for H2(N1,N9)ade [Cu(HEDTA)
(H2O)]·2H2O (EGOWIG in Cambridge Structural Database (CSD), Hade = adenine), in which H-bonds
and π,π-stacking played relevant roles in the anion–cation interaction and the recognition between
two pairs of ions, respectively. Factors contributing in such remarkable differences are discussed on
the basis of the additional presence of the exocyclic 2-amino group in 2,6-diaminopurinium(1+) ion.This research was funded by the Excellence Network ‘Metal Ions in Biological Systems’ MetalBio
CTQ2017-90802-REDT, the Research group FQM-283 (Junta de Andalucía) and MICIU/AEI of Spain (project
CTQ2017-85821-R FEDER funds)
Novel Cd (II) Coordination Polymers Afforded with EDTA or Trans-1,2-Cdta Chelators and Imidazole, Adenine, or 9-(2-Hydroxyethyl) Adenine Coligands
Three mixed-ligands of Cd(II) coordination polymers were unintentionally obtained: {[Cd(µ3-EDTA)(Him)·Cd(Him)(H2O)2]·H2O}n (1), {[Cd(µ4-CDTA)(Hade)·Cd(Hade)2]}n (2), and {[Cd(µ3-EDTA)(H2O)·Cd(H9heade)(H2O)]·2H2O}n (3), having imidazole (Him), adenine (Hade) or 9-(2-hydroxyethyl)adenine (9heade) as the N-heterocyclic coligands. Compounds 2 and 3 were obtained by working with an excess of corresponding N-heterocyclic coligands. The single-crystal X-ray diffraction structures and thermogravimetric analyses are reported. The chelate moieties in all three compounds exhibit hepta-coordinated Cd centers, whereas the non-chelated Cd center is five-coordinated in 1 and six-coordinated in 2 and 3. Him and Hade take part in the seven-coordinated chelate moieties in 1 and 2, respectively. In contrast, 9heade is unable to replace the aqua ligand of the chelate [Cd (EDTA) (H2O)] moiety in 3. The thermogravimetric analysis (TGA) behavior of [Cd (H2EDTA) (H2O)]·2H2O in 1 and 3 leads to a residue of CdO, whereas the N-rich compound 2 yields CdO·Cd(NO3)2 as a residue. Density functional theory (DFT) calculations along with molecular electrostatic potential (MEP) and quantum theory of atoms-in-molecules computations were performed in adenine (compound 2) and (2-hydroxyethyl)adenine (compound 3) to analyze how the strength of the H-bonding and π-stacking interactions, respectively, are affected by their coordination to the Cd-metal centerThis research was funded by the Excellence Network “Metal Ions in Biological Systems” MetalBio CTQ2017-90802-REDT, the Research group FQM-283 (Junta de Andalucía), and MICIU/AEI of Spain (project CTQ2017-85821-R FEDER funds)S
Transversalidad de las técnicas de modelado matemático en Farmacia con la ayuda de una hoja de cálculo
The implementation of the EHEA in Pharmacy studies will lead to foster student self-learning. This
way the student abilities to apply knowledge, learned in some subjects, to search knowledge in any
other will be tested. Among such applicative knowledge, we can consider the mathematical modelling
techniques, included in the field of Mathematics. This article draws attention to the usefulness of
popular spreadsheets for Pharmacy students interested in the application of mathematical modelling techniques. Roughly speaking, a pharmacy student will probably have to perform mathematical calculations and experimental data visualizations, especially in the practice syllabus of some of his subjects. The use of
software is important in this respect, not only in the learning step of the mathematical concepts in the
corresponding math subject, but also in its application to other Pharmacy subjects. What application
software can be chosen for the students? Although there are many candidates, a spreadsheet offers
some capabilities that make it ideal for a Pharmacy student: short learning time, wide availability on
different computer platforms and flexibility to carry out a variety of computational tasks.
Finally, we present a Web page which provides self-learning material to Pharmacy students for
harnessing the potential offered by the spreadsheets Excel (Microsoft Office) and Calc (OpenOffice.org) in the study of their subjects in Pharmacy.La implantación del EEES en las titulaciones en Farmacia va a significar la potenciación del
autoaprendizaje por parte del alumno. Esto va a poner a prueba la capacidad de aplicar conocimientos
adquiridos en unas materias, para entender y conocer otras. Entre dichos conocimientos, se encuentran
las técnicas de modelado matemático, incluidas en el campo de las Matemáticas. El presente artículo
reflexiona acerca de la utilidad de las populares hojas de cálculo como software dirigido al alumno.
Un alumno de Farmacia, probablemente, tendrá que realizar cálculos matemáticos y representaciones
gráficas con datos experimentales, muy especialmente en las prácticas de algunas de sus asignaturas.
La utilización de un software es, en este sentido, especialmente importante, no sólo en la fase de
aprendizaje de dichos conocimientos matemáticos en la correspondiente asignatura del título, sino a la
hora de disponer de una herramienta que facilite su aplicación en otras. ¿Qué software podemos elegir
para el alumno? A pesar de que existen multitud de candidatos, una hoja de cálculo reúne una serie de
características que la hacen idónea para un alumno de Farmacia: corto tiempo de aprendizaje, amplia
disponibilidad en distintas plataformas y flexibilidad para poder realizar una gran diversidad de tareas,
entre otras propiedades.
Finalmente, como ejemplo se presenta una página Web,
http://www.ugr.es/~focana/farmaspreadsheet.htm, que facilita material para ayudar al alumno de
Farmacia a aprovechar las posibilidades que ofrecen las hojas de cálculo Excel (Microsoft Office) y Calc (OpenOffice.org) en el estudio de sus asignaturas en Farmacia
Dicopper(II)-EDTA Chelate as a Bicephalic Receptor Model for a Synthetic Adenine Nucleoside
In the extensive field of metal ions, their interactions with nucleic acids, and their constituents,
the main aim of this work is to develop a metal chelate suitable to recognize two molecules of an adenine
nucleoside. For this purpose, the dinuclear chelate Cu2
(µ-EDTA) (ethylenediaminetetraacetate(4-) ion
(EDTA)) is chosen as a bicephalic receptor model for N9-(2-hydroxyethyl)adenine (9heade). A one-pot
synthesis is reported to obtain the compound [Cu2
(µ2
-EDTA)(9heade)2
(H2O)4
]·3H2O, which has been
characterized by single-crystal X-ray diffraction and various spectral, thermal, and magnetic methods.
The complex unit is a centro-symmetric molecule, where each Cu (II) center is chelated by a half-EDTA,
and is further surrounded by an N7-dentate 9heade nucleoside and two non-equivalent trans-O-aqua
molecules. The metal chelate-nucleoside molecular recognition is referred to as an efficient cooperation
between the Cu-N7(9heade) coordination bond and a (9heade)N6-H···O(carboxyl, EDTA) interligand
interaction. Theoretical calculations are also made to account for the relevance of this interaction. The
extreme weakness with which each water molecule binds to the metal center disturbs the thermal
stability and the infrared (FT-IR) and electron spin resonance (ESR) spectra of the compound.Agencia Estatal de Investigación, Ministerio de Ciencia,
Innovación y Universidades (MICIU) from SpainFEDER-EU (project nos.
PGC2018-102047-B-I00 and CTQ2017-85821-R)Junta de Andalucía (research group FQM-283)University of Granada (project ref. PPJIA2019-03
The emerging role of auxins as bacterial signal molecules: Potential biotechnological applications
This study was supported through grants from the
Spanish Ministry for Science and Innovation/Agencia
Estatal de Investigación 10.13039/501100011033
(PID2019-103972GA-I00 to M.A.M., PID2020-
112612GB-I00 to T.K. and PID2020-116261GB-I00 to
J.A.G.) and the Junta de Andalucía (grant P18- FR-1621
to T.K.). A.R. was supported by the Ramon y Cajal
R&D&i Programme (RYC2019- 026481-I) from the
Spanish Ministry for Science and Innovation/Agencia
Estatal de Investigación 10.13039/501100011033 y
FSE ‘El FSE invierte en tu futuro’.Microorganisms are exposed in their natural niches to a wide diversity of sig-
nal molecules. Specific detection of these signals results in alterations in mi-
crobial metabolism and physiology. Auxins like indole-3-acetic acid are key
phytohormones that regulate plant growth and development. Nonetheless,
auxin biosynthesis is not restricted to plants but is ubiquitous in all kingdoms
of life. This wide phylogenetic distribution of auxins production, together with
the diversity of regulated cellular processes, have made auxins key intra-
and inter-kingdom signal molecules in life modulating, for example microbial
physiology, metabolism and virulence. Despite their increasing importance as
global signal molecules, the mechanisms by which auxins perform their regu-
latory functions in microorganisms are largely unknown. In this article, we
outline recent research that has advanced our knowledge of the mechanisms
of bacterial auxin perception. We also highlight the potential applications of
this research in aspects such as antibiotic production, biosensor design, plant
microbiome engineering and antivirulence therapies.Spanish Ministry for Science and Innovation/Agencia Estatal de Investigacion
PID2020-112612GB-I00,
PID2020-116261GB-I00,
RYC2019- 026481-IJunta de Andalucia
P18-FR-1621,
PID2019-103972GA-I0
Geominero Museum: past, present and… the future?
[EN] The Geominero Museum is a public museum that currently depends on the IGME - CSIC National Centre. A valuable geological heritage made up of more than 100,000 specimens of fossils, minerals and rocks is kept by the Museum, whose origin dates back to the second half of the 19th century. Its objectives are to conserve, disseminate and research the richness and diversity of the palaeontological, mineralogical and petrological heritage from all Spanish regions, as well as from former Spanish colonies and some representative sites of the geological record of the world. From the 1990s until 2021, the Museum has worked in three areas: research, curation-restoration and education-dissemination. A vocational and consolidated staff has achieved to position the Museo Geominero among the national and international distinguished geological museums. However, as of Royal Decree 202/2021, 30th March, the Museum missed one of its main roles: research. The reduction in Geominero Museum staff, therefore the capacities to take on museum objectives are also reduced (see the definition of a Museum by International Council of Museums, ICOM), the current weakness of the synergies previously created between researchers, curators and disseminators and a lack of expertise staff on educational and dissemination activities, have led the Museum to become a mere exhibition space for exhibiting specimens. It does not seem a very promising future for a Museum that has been a main window to the world for such an emblematic, prestigious and a long and fruitful history institution as the Spanish Geological and Mining Institute (IGME).Peer reviewe
Nurses' perceptions of aids and obstacles to the provision of optimal end of life care in ICU
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