Reseñas

Obra ressenyada: Luis MONTIEL, El rizoma oculto de la psicología profunda. Gustav Meyrink y Carl Gustav Jung. Madrid : Frenia, 2012

A structural, spectroscopic and theoretical study of an o-vanillin Schiff base derivative involved in enol-imine and keto-amine tautomerism

The potassium salt of the Schiff base obtained by condensation of 2-hydroxy-3-methoxybenzaldehyde (o-vanillin) and 2-aminoethanesulfonic acid (taurine) in a methanol potassium hydroxide solution was characterized by crystallographic, spectroscopic and DFT methods. The compound crystallizes in the monoclinic C2/c space group with a = 37.539(4), b = 5.9129(4), c = 26.321(5) Å, β = 121.10(2)° and Z = 8 molecules per unit cell. The crystallographic data reveal that two different anionic molecules, which constitute a tautomeric pair, coexist in the crystal. This finding is supported by FTIR, Raman and electronic measurements in methanol solution. The main crystallographic differences between the bonding structures occur along the shortest chemical path linking the oxygen and the nitrogen atom of the OH and CN group. Both tautomeric forms are stabilized by strong O–H⋯N and N–H⋯O intramolecular hydrogen bonds. Optimized geometrical parameters and calculated spectroscopic features obtained by DFT calculations show a very good agreement with the experimental data. Moreover, 1H NMR, 13C NMR and electronic measurements in DMSO solution show the prevalence of the enol-imine tautomer in this solvent.Centro de Química InorgánicaInstituto de Física La Plat

Synthesis and characterization of a series of isoniazid hydrazones : Spectroscopic and theoretical study

A family of hydrazones of isoniazid and a group of hydroxybenzalaldehydes (vanillin, 5-bromovanillin, 5- chlorosalicylaldehyde and 5-bromosalicylaldehyde) were obtained and fully characterized. The results, including theoretical data, are comparatively analyzed along with the already reported hydrazone of ovanillin. The crystal structures of three compounds were determined. The hydrazones obtained from halogenated aldehydes are isomorphic and chiral to each other. Structures are further stabilized by (pyr) NHþ/Cl and OwH/Cl bonds. The vanillin hydrazone shows a conformer that differs from the previously reported. Neighboring molecules are linked to each other through OH/N(pyr) bonds, giving rise to a nearly planar polymeric structure. The conformational space was searched and geometries were optimized both in the gas phase and including solvent effects by DFT. Results are extended to describe the 5-bromovanillin hydrazone. FTIR, NMR and electronic spectra were measured and assigned with the help of computational calculations.Centro de Química InorgánicaInstituto de Física La Plat

A theoretical study of a family of new quinoxaline derivatives

Hybrid density functional calculations are performed on a series of 21 new quinoxaline derivatives, which would likely exhibit important biological activities. Optimized geometries, harmonic vibrational frequencies, and 1H chemical shifts are reported and compared with experimental data when available. In addition, melting points of 75 derivatives are predicted resorting to the Quantitative Structure–Property Relationship (QSPR) Theory, doing the variable selection by means of the Replacement Method and using 875 theoretical descriptors obtained from Dragon 5 software. The best relationship found has seven descriptors with R = 0.8818 and Rl-10%-o = 0.7705.Centro de Química InorgánicaInstituto de Investigaciones Fisicoquímicas Teóricas y Aplicada

Structure, tautomerism, spectroscopic and DFT study of o-vanillin derived Schiff bases containing thiophene ring

Two Schiff bases derived from o-vanillin (o-HVA), a well-known antioxidant hydroxo aldehyde, have been obtained from condensation with 2-thiophenecarboxilic acid hydrazide (TPNNH) and 2-thiophenemethylamine (TPNH2), respectively. The inclusion of thiophene is based on its significance in the development of effective therapeutic agents. The study of the compounds oVATPNNH and oVATPNH2 includes solid state structural and spectroscopic analysis by single-crystal X-ray diffraction and vibrational spectroscopy (FTIR and Raman). The crystal structure of oVATPNH2 shows a peculiar rotational disorder in the heterocycle. Tautomeric equilibria in solution, which depends on the molecule structure and the nature of the solvent, were analysed by means of 1H and 13C{1H} NMR along with electronic spectroscopy. Tautomerism plays an important role not only in the molecular interactions but also in the behaviour of the Schiff base when acting as a ligand in coordination compounds. Results obtained from DFT calculations were used in the interpretation of the experimental data and in the spectral assignments.CONICET and UNLP, Argentina and by Ministerio de Economía y Competitividad Español (CTQ2014-58812-C2-1-R, CTQ2015-70371-REDT

Synthesis, crystal structure, spectroscopic characterization, DFT calculations and cytotoxicity assays of a new cu(II) complex with an acylhydrazone Ligand derived from thiophene

A new Cu(II) complex is synthetized by the reaction of copper nitrate and a N-acylhydrazone ligand obtained from the condensation of o-vanillin and 2-thiophecarbohydrazide (H2L). The solid-state structure of [Cu(HL)(H2O)](NO3)·H2O, or CuHL for simplicity, was determined by X-ray diffraction. In the cationic complex, the copper center is in a nearly squared planar environment with the nitrate interacting as a counterion. CuHL was characterized by spectroscopic techniques, including solid-state FTIR, Raman, electron paramagnetic resonance (EPR) and diffuse reflectance and solution UV-Vis electronic spectroscopy. Calculations based on the density functional theory (DFT) assisted the interpretation and assignment of the spectroscopic data. The complex does not show relevant antioxidant activity evaluated by the radical cation of 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) method, being even less active than the free ligand as a radical quencher. Cytotoxicity assays of CuHL against three human tumor cell lines, namely MG-63, A549 and HT-29, revealed an important enhancement of the effectiveness as compared with both the ligand and the free metal ion. Moreover, its cytotoxic effect was remarkably stronger than that of the reference metallodrug cisplatin in all cancer cell lines tested, a promissory result in the search for new metallodrugs of essential transition metals.Fil: Rodríguez, María R.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; ArgentinaFil: Balsa, Lucia Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; ArgentinaFil: Piro, Oscar Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Etcheverría, Gustavo A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: García Tojal, Javier. Universidad de Burgos; EspañaFil: Pis Diez, Reinaldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; ArgentinaFil: Leon, Ignacio Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; ArgentinaFil: Parajón Costa, Beatriz Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; ArgentinaFil: Gonzalez Baro, Ana Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; Argentin

Structure, tautomerism, spectroscopic and DFT study of o-vanillin derived Schiff bases containing thiophene ring

Two Schiff bases derived from o-vanillin (o-HVA), a well-known antioxidant hydroxo aldehyde, have been obtained from condensation with 2-thiophenecarboxilic acid hydrazide (TPNNH) and 2- thiophenemethylamine (TPNH2), respectively. The inclusion of thiophene is based on its significance in the development of effective therapeutic agents. The study of the compounds oVATPNNH and oVATPNH2 includes solid state structural and spectroscopic analysis by single-crystal X-ray diffraction and vibrational spectroscopy (FTIR and Raman). The crystal structure of oVATPNH2 shows a peculiar rotational disorder in the heterocycle. Tautomeric equilibria in solution, which depends on the molecule structure and the nature of the solvent, were analysed by means of 1H and 13C{1H} NMR along with electronic spectroscopy. Tautomerism plays an important role not only in the molecular interactions but also in the behaviour of the Schiff base when acting as a ligand in coordination compounds. Results obtained from DFT calculations were used in the interpretation of the experimental data and in the spectral assignments.Centro de Química Inorgánic

Synthesis, crystal structure and cytotoxicity assays of a copper(II) nitrate complex with a tridentate ONO acylhydrazone ligand. Spectroscopic and theoretical studies of the complex and its ligand

The new copper complex, [Cu(HL)(OH2)2](NO3), including the tridentate N-acyhydrazone derived from 4-hydroxy-benzohydrazide and 2-hydroxy-3-methoxybenzaldehyde, (H2L), has been synthesized and characterized in the solid state and in solution by spectroscopic (FTIR, Ra, UV–vis, EPR) methods. The results were compared with those obtained for the hydrazone ligand and complemented with computational methods based on DFT. The crystal structure of the complex has been determined by X-ray diffraction. It crystallizes in the triclinic space group with Z = 2. The Cu(II) ion is in a distorted square pyramidal environment, coordinated to a planar HL- anion acting as a tridentate ligand. The 5-fold coordination is completed with two water molecules. It is arranged in the lattice as H-bonded ribbon-like polymers that extends along the [1 2 1] crystal direction. The cytotoxicity of the complex together with that of the H2L ligand and the copper ion were evaluated in vitro against five different human cancer cell lines namely A549 (lung), MG-63 (bone), MCF-7 and MDA-MB-231 (breast) and Jurkat (leukemia). The copper complex inhibits the cell viability in a dose dependent manner with a greater potency than the H2L ligand and the free copper ion displaying even higher antitumor activity than the well-known anticancer metallodrug cisplatin.CONICET (PIP 11220130100651CO and PIP 0034), UNLP (111/X673) and ANPCyT (PICT 2014-2223) of Argentina. Consejería de Educación CyL and FFEDER BU076U16, BU022G18 and Ministerio de Economía y Competitividad CTQ2016-75023-C2-1-P and CTQ2015-70371-REDTMetDrugs Network (Spain

Cu(ii) and Zn(ii) complexes with a poly-functional ligand derived from o-vanillin and thiophene. Crystal structure, physicochemical properties, theoretical studies and cytotoxicity assays against human breast cancer cells

The interaction of a poly-functional ligand derived from o-vanillin and 2-thiophenemethylamine (oVATPNH2) with transition metal ions Cu(II) and Zn(II) leads to the formation of stable coordination compounds, namely [Cu(oVATPNH2)2] and [Zn(oVATPNH2)2]. Their crystal structures have been determined by X-ray diffraction methods. Two molecules of the deprotonated ligand acting in a bidentate fashion build a nearly square planar environment around Cu(II) and a distorted tetrahedral coordination arrangement for Zn(II). The complexes were characterized by spectroscopic techniques, including solid state FTIR, Raman, EPR and diffuse reflectance and solution UV-vis and EPR. Their thermal behavior has been analyzed by means of TGA and DTA. DFT theoretical studies, using computational methods based on DFT, were employed to assist the interpretation and assignment of spectroscopic data. Cytotoxicity assays against two human breast cancer cell lines, namely MCF-7 and MDA-MB-231, revealed an enhancement of the effectiveness of the complexes as compared with both the ligand and the free metal ions. The results for the copper compound are promising, as its cytotoxic effect was stronger than the reference metallodrug cisplatin in both cancer cell lines tested.CONICET-CCT-La Plata (PIP 0651 and 0034), ANPCyT (PICT 2016-1574) and UNLP (11/X-473) (Argentina) and also by Consejerı´a de Educacio´n CyL and FFEDER BU076U16, BU022G18 and Ministerio de Economı´a y Competitividad CTQ2016-75023-C2-1-P and CTQ2015-70371- REDT MetDrugs Network (Spai