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We used 1H, 13C HRMAS and genomic analysis to investigate regionally the transition from oxidative to glycolytic phenotype and its relationship with altered gene expression in adjacent biopsies through the brain of rats bearing C6 gliomas. Tumor-bearing animals were anesthetized and infused with a solution of [1-13C]-glucose, and small adjacent biopsies were obtained spanning transversally from the contralateral hemisphere (regions I and II), the right and left peritumoral areas (regions III and V, respectively), and the tumor core (region IV). These biopsies were analyzed by 1H, 13C HRMAS and by quantitative gene expression techniques. Glycolytic metabolism, as reflected by the [3-13C]-lactate content, increased clearly from regions I to IV, recovering partially to physiological levels in region V. In contrast, oxidative metabolism, as reflected by the [4-13C]-glutamate labeling, decreased in regions I-IV, recovering partially in region V. This metabolic shift from normal to malignant metabolic phenotype paralleled changes in the expression of HIF1α, HIF2α, HIF3α genes, downstream transporters, and regulatory glycolytic, oxidative, and anaplerotic genes in the same regions. Together, our results indicate that genetic and metabolic alterations occurring in the brain of rats bearing C6 gliomas colocalize in situ and the profile of genetic alterations in every region can be inferred from the metabolomic profiles observed in situ by multinuclear HRMAS., The present work was supported by grants SAF2014-53739-R, SAF2017-83043-R, and B2017/BMD-3688 from the Ministry of Economy and Competitiveness and from the Community of Madrid to PL-L and SC, Acciones Integradas IH-HI2006-0101 from the Ministry of Science and Technology to L.S. and S.C. The authors are indebted to Mr. Javier Pérez CSIC for careful drafting of the illustrations and to Mrs. Teresa Navarro CSIC for granting access to the Biomedical NMR Services of the Institute of Biomedical Research “Alberto Sols” CSIC.

High Resolution Magic Angle Spinning (HR-MAS) is an NMR technique that can be applied to semi-solid samples. Flavedo, albedo, pulp, seeds, and oil gland content of lemon and citron were studied through HR-MAS NMR spectroscopy, which was used directly on intact tissue specimens without any physicochemical manipulation. HR-MAS NMR proved to be a very suitable technique for detecting terpenes, sugars, organic acids, aminoacids and osmolites. It is valuable in observing changes in sugars, principal organic acids (mainly citric and malic) and ethanol contents of pulp specimens and this strongly point to its use to follow fruit ripening, or commercial assessment of fruit maturity. HR-MAS NMR was also used to derive the molar percentage of fatty acid components of lipids in seeds, which can change depending on the Citrus species and varieties. Finally, this technique was employed to elucidate the metabolic profile of mold flavedo.

We present the synthesis and characterization of a novel copolymer from benzodithiophene and alkylsulfanyl-bithiophene units, poly[4,8-bis(2-ethylhexyloxy)benzo[1,2-b:4,5-b′]dithiophene-alt-4,4′-bis(octylsulfanyl)-2,2′-bithiophene] (PolyS). The structural, electrochemical and photophysical properties of PolyS were investigated by gel permeation chromatography (GPC), thermogravimetric analysis (TGA), NMR, UV–vis, photoluminescence (PL) spectroscopy and cyclic voltammetry (CV). PolyS was used to fabricate bulk-heterojunction polymer solar cells (PSCs) in combination with the [60]PCBM and [70]PCBM (electron acceptors). The device realized using [70]PCBM shows a better current output due to the increased absorption of the blend film compared to the PolyS:[60]PCBM one. The power conversion efficiency of the best PSC realized is 2.3% under 100 mW/cm2 AM 1.5 G illumination.

The water-soluble poly{trimethyl-[7-(3-thienylsulfanyl)heptyl]ammonium iodide-co-thiophene} (PTN+Me3) forms aggregates whose size span a large range of values, depending on solvent, concentration and film formation conditions. Larger aggregates were detected by atomic force microscopy and dynamic light scattering, smaller ones by DOSY NMR, UV–visible and fluorescence. All techniques indicate a reduced aggregation of PTN+Me3 in DMSO relative to water and a marked de-aggregation of PTN+Me3 in water following addition of bile-acid anions such as deoxycholate and ursodeoxycholate. The latter effect shows itself through a very large enhancement of the polymer photoluminescence likely caused by disruption of aggregated non-emissive exciton traps. A tailored combination of electrostatic and hydrophobic interactions between the polymer and the bile-acid anions seems to be necessary to achieve this effect. These observations suggest that this polythiophene might provide a basis for the development of fluorescent sensors suitable for the detection of medium-sized amphiphilic biomolecules.

The charge-transfer and spectral properties of two octithiophenes, namely 4',4''',3'(v),3(v)'-tetra(octylsulfanyl)-2,2':5',2'':5'',2''':5''',2'(v):5'(v),2(v):5(v),2(v)':5(v)',2(v)''-octithiophene and 4,3'',4(v),4(v)''-tetrabromo-4',4''',3'(v),3(v)'-tetra[(R)-2-methylbutylsulfanyl]-2,2':5',2'':5'',2''':5''',2'(v):5'(v),2(v):5(v),2(v)':5(v)',2(v)''-octithiophene, OT1 and OT2, respectively, are characterized by cyclic voltammetry and spectroelectrochemistry under ultradry conditions. The analysis of the voltammetric results shows the formation of up to the dication for both OT1 and OT2 and up to the tetraanion (OT1) and trianion (OT2) anions. The optical properties of the OT1 (2+, 1+, neutral, 1-, 2-) species were probed by in situ UV-vis-NIR spectroelectrochemistry. The calculated standard potentials at the B3LYP/cc-pVTZ level of the theory allowed the rationalization of the experimental electrochemical results. The UV-vis-NIR spectra were successfully compared with the theoretical electronic transitions and oscillator strength data obtained by time-dependent B3LYP/6-31G* calculations. Theoretical redox potentials and optical transitions properties are calculated including "the solvent effect" within the CPCM model. The consistency obtained between experimental and theoretical results indicates the existence of the hypothesized high-spin/high-charge p- and n-doped electronic states for the OT1 and OT2 octithiophenes here studied.

Different routes, based on the Stille coupling, to the obtainment of a polythiophene bearing a carboxyhexylsulfanyl chain every two thiophene rings (PTCOOH) are here reported and discussed. Two PTCOOHs with different chain lengths were obtained: the shorter by hydrolysis of a polymeric ester precursor and the longer by direct Stille coupling from suitable monomers. They possess similar electrochemical properties but behave differently when aggregation and fluorescence are concerned. The PTCOOH obtained by hydrolysis is found to be fluorescent in a good solvent such as THF, and its fluorescence quantum yield decreases as the extent of aggregation increases. The polymer obtained by direct Stille coupling is less fluorescent, consistently with its proneness to aggregate. The PTCOOH obtained by hydrolysis is therefore more promising in view of the build-up of solid-state devices with exploitable fluorescence properties.

The synthetic approach to methyl N-(tert-butoxycarbonyl)- S-(3-thienyl)-L-cysteinate (1) and methyl N-(tert-butoxycarbonyl)- S-[2-(3-thienyl)ethyl]-L-cysteinate (2) through tosylate intermediates is reported and discussed. These compounds, which combine the properties of the cysteine side-chain with those of the thiophene ring represent both potential bioactive molecules and interesting synthons for the development of new materials.

The reaction of 4-methyl-pyrrolidin-2-ones, chlorinated at the C(3) and C(6) positions, with n-propylamine constitutes a new method for the preparation of 5-propylimino-pyrrolidin-2-ones or 3-pyrrolin-2-ones in generally good yields. The transformation involves a series of eliminations, substitutions and double bond shifts. This constitutes a remarkable example of a functional rearrangement.

The dinuclear hydroxo complex cis-[L(2)Pt(mu-OH)](2)(NO(3))(2) (L = PMePh(2), 1), in CH(2)Cl(2), CH(3)CN, or DMF solution, deprotonates the NH(2) group of 9-methyladenine (9-MeAd) to give the complex cis-[L(2)Pt[9-MeAd(-H)]](3)(NO(3))(3), 2, which was isolated in good yield. The X-ray structure shows that the nucleobase binds symmetrically the metal centers through the N(1),N(6) atoms forming a cyclic trimer with Pt...Pt distances in the range 5.202(1)-5.382(1) A. Dissolution of 2 in DMSO or DMF determines the partial (or total) dissociation of the cyclic structure to form several fragments. A multinuclear NMR analysis of the resulting mixture supports the presence of the mononuclear species cis-[L(2)Pt[9-MeAd(-H)]](+), 3, in which the deprotonated nucleobase chelates the metal center with the N(6),N(7) atoms. Addition of a stoichiometric amount of the nitrato complex cis-[L(2)Pt(ONO(2))(2)] (L = PMePh(2), 4) to a DMSO or DMF solution of 2 affords quantitatively the diplatinated compound cis-[L(2)Pt(ONO(2))[9-MeAd(-H)]PtL(2)](NO(3))(2), 5. The single-crystal X-ray analysis shows that the adenine behaves as a tridentate ligand bridging two cis-L(2)Pt units at the N(1) and N(6),N(7) sites, respectively [Pt(1)-N(1) = 2.109(5) A, Pt(2)-N(6) = 2.095(7) A, Pt(2)-N(7) = 2.126(7) A]. The N(1)-bonded metal center completes the coordination sphere through an oxygen atom of a nitrate group, and its coordination plane is arranged orthogonally with respect the second one. The Pt-O distance [2.109(5) A] is similar to those found in the nitrato complex 4 [2.110 A, average]. The related complex cis-[[L(2)Pt(ONO(2))](2)(9-MeAd)](NO(3))(2), 6, containing the neutral adenine platinated at the N(1),N(7) atoms, was isolated and its stability in solution investigated by NMR spectroscopy. In DMSO, 6 undergoes decomposition forming a mixture of the species 4, 5, and the adenine mono- and bis-adducts cis-[L(2)Pt(9-MeAd)(DMSO)](2+), 7, and cis-[L(2)Pt(9-MeAd)(2)](2+), 8, respectively. This last complex, quantitatively formed upon addition of 9-MeAd (Pt/adenine = 1:2) to the mixture, was also isolated and characterized.

A sonogel–carbon–polythiophene microstructured electrode has been synthesised via sonocatalytic procedure. The composite material was characterised by cyclic voltammetry, atomic force microscopy and optical microscopy. A comparison with a similar polythiophene directly cast on a platinum electrode has been made. In contrast with the degrading behaviour (overoxidation) observed at sufficiently positive potentials for alkylsulphanyl substituted polythiophenes cast on the electrode surface, the entrapment of the polymer inside a composite material drastically enhances the stability of the redox-active phase towards irreversible oxidation. In addition, the sonogel–carbon–polythiophene composite represents a good approach to test and, possibly, exploit the electrochemical properties of the polymer which, due to its complete insolubility in the common organic solvents, cannot be adequately cast on an electrode surface or electrosynthesised.

A new copolymer bearing a cysteine Moiety, designed for molecular interaction, metal-ion detection, and chiral recognition, was synthesised starting from the dibromo derivative of methyl N-(tert-butoxycarbonyl)-S-thien-3-ylcysteinate and distannylthiophene through a Stille coupling reation. UV-vis spectroscopy, circular dichroism, NMR spectroscopy, and gel permeation chromatography analyses evidenced that this polymer is able to form self-assembling structures, through the formation of a hydrogen-bond network, not only in the solid state but also in solution.

A dramatic variation of the magnetic coupling in large polyiron clusters can be induced by exploiting host−guest interactions. Subtle structural changes and much weaker antiferromagnetic interactions are the result of the substitution of Na+ with Li+ in the hollow core of the cyclic complex [Fe6(OCH3)12(dbm)6] (Hdbm = dibenzoylmethane).

3,4′-Dibromo-2,2′-bithiophene was converted, in high yield, into the corresponding dibutoxy derivative. The 1H 13C and nmr data are discussed in comparison with those of 3,3′- and 4,4′-dibutoxy-2,2′-bithiophene in relation to regiochemistry.

The reaction of ferric chloride and β-diketones (HL) in alkaline methanol solution represents a good synthetic route to hexairon(III) clusters [MFe6-(OCH3)12(L)6]+ (M = Na, Li), which exhibit an unusual sixfold molecular symmetry. Single-crystal X-ray diffraction showed that the six octahedrally coordinated iron(III) ions define a ring and are linked by twelve bridging methoxide ligands. The resulting [Fe6(OCH3)12] skeleton has the remarkable property of acting as a host for an alkali-metal ion both in the solid state and in organic solution, as demonstrated by 23Na and 7Li NMR experiments. The magnetic behavior of these systems is consistent with the presence of a nonmagnetic S = 0 ground state and of antiferromagnetic exchange interactions between the high-spin ferric ions. The energy of the excited states was studied in detail by high-field DC and pulsed-field differential magnetization experiments at 0.7 and 1.5 K. Single-crystal susceptibility measurements at variable temperature revealed a sizeable magnetic anisotropy, which has been successfully analyzed in terms of single-ion and dipolar contributions. The results are relevant to research into the origin of superparamagnetic-type behavior in transition-metal clusters.

The interaction of diclofenac sodium salt (DCFNa) and two cyclodextrins, β-cyclodextrin (βCD) and 2-hydroxypropyl-β-cyclodextrin (HPβCD), studied in D2O solution with different NMR techniques (1H, 13C NMR, ROESY experiments, NMR titrations), shows the existence of multiple equilibria involving 1:1 and 2:1 guest–host complexes.

The NMR spectra of a number of 2,4-disubstituted 1,3-dioxolanes have been recorded and the proton chemical shifts and coupling constants derived from complete spectral analysis. Vicinal coupling constants were found to be dependent on the substituent at C-4 and this effect is more pronounced for J(trans) of the C-4-C-5 fragment. These coupling constants also indicate a homogeneous behaviour within a series with either a cis or trans configuration, although the cis behaviour differs from that of trans isomers. This has been interpreted in terms of definite ring conformations in substituted derivatives, while the unsubstituted 1,3-dioxolane undergoes free pesudorotation. Calculations of coupling constants were performed by semi-empirical MO methods, both for unsubstituted 1,3-dioxolane and for C-4 substituted derivatives in a large number of conformations, in order to compare calculated and experimental values; the correct order of J(cis) and J(trans) for 1,3-dioxolane is obtained only by employing energies from ab-initio MO calculations averaged over the pseudorotation circuit. For the C-4 substituted compounds calculated coupling constants were employed in a ‘trial and error’ process for the identification of the preferred conformations of these compounds; a set of two torsional angles for each compound was derived which allows a tentative description of the geometry of each molecule. A criticism of these geometries is given according to the evidence available on the structure of substituted 1,3-dioxolanes.