Abstract
Luminescent metal-organic frameworks (LMOFs) are promising materials for lighting and sensing applications. Herein, exposure of the highly luminescent Zn-2(bpdc)(2)(bpee) MOF (H(2)bpdc = 4,4'-biphenyldicarboxylic acid and bpee = 1,2-bipyridylethene) to subppm amine contents turns on a new absorption band unambiguously ascribed to free bpee molecules concomitant with the gradual appearance of a new photoluminescence band at shorter wavelengths. These findings combined with Fourier-transform infrared spectra, powder X-ray diffraction and thermogravimetric analysis of exposed LMOF powders confirm that bpee ligands are exchanged by amines and released inside the LMOF, triggering absorption and luminescence features which can be exploited for highly sensitive amine recognition. This principle was demonstrated in mixed matrix membranes (MMMs) prepared by a simple solvent-free method consisting of mixing Zn-2(bpdc)(2)(bpee) with dimethylvinyl-terminated dimethylsiloxane and dimethylhydrogen siloxane. This method enabled the production of free-standing, permeable, and highly transparent MMMs which showed enormous potential and sensitivity to the detection of amines in gas phase and aqueous medium.

Abstract
In this work we report the synthesis and characterization of a set of 3-hydroxy-4-pyridinone copper(II) complexes with variable lipophilicity. EPR spectroscopy was used to characterize the structure of copper(II) complexes in solution, and as a tool to gain insight into solvent interactions. EPR spectra of solutions of the [CuL2] complexes recorded in different solvents reveal the presence of two copper species whose ratio depends on the nature of the solvent. Investigation of EPR spectra in the pure solvents methanol, dimethylsulfoxide, dichloromethane and their 50% (v/v) mixtures with toluene allowed the characterization of two types of copper signals (g(zz) = 2.30 and g(zz) = 2.26) whose spin-Hamiltonian parameters are consistent with solvated and non-solvated square-planar copper(II) complexes. Regarding the potential biological application of ligands and complexes and to get insight into the partition properties in water-membrane interfaces, EPR spectra were also obtained in water-saturated octanol, an aqueous solution buffered at pH = 7.4 and liposome suspensions, for three compounds representative of different hydrolipophilic balances. Analysis of the EPR spectra obtained in liposomes allowed establishment of the location of the complexes in the water and lipid phases. In view of the results of this work we put forward the use of EPR spectroscopy to assess the affinity of copper(II) complexes for a hydrophobic environment and also to obtain indirect information about the lipophilicity of the ligands and similar EPR silent complexes.

Abstract
The two new fluorescent ligands RosCat1 and RosCat2 contain catechol receptors connected to rosamine platforms through an amide linkage and were synthesized by using microwave-assisted coupling reactions of carboxyl- or amine-substituted rosamines with the corresponding catechol units and subsequent deprotection. RosCat1 possesses a reverse amide, whereas RosCat2 has the usual oriented amide bond (HNCO vs. CONH, respectively). The ligands were characterized by means of NMR spectroscopy, mass-spectrometry, and DFT calculations and X-ray crystallography studies for RosCat1. The influence of the amide linkage on the photophysical properties of the fluorescent ligands was assessed in different solvents and showed a higher fluorescence quantum yield for RosCat1. The coordination chemistry of these ligands with a Fe-III center has been rationalized by mass-spectrometric analysis and semiempirical calculations. Octahedral Fe-III complexes were obtained by the chelation of three RosCat1 or RosCat2 ligands. Interestingly, the unconventional amide connectivity in RosCat1 imposes the formation of an eight-membered ring on the chelate complex through a salicylate-type mode of coordination.

Abstract
We report the synthesis and physicochemical properties of a new tripodal hexadentate chelator (catTHC) synthesized by reaction of a flexible tripodal backbone with three bidentate catechol units. To improve the efficiency of the amide coupling reaction, classical conditions using two pairs of coupling reactants were tested, and a significant reduction in reaction time was achieved by using microwave irradiation with the reactants DCC/HOBt. Subsequent removal of the benzyl protecting groups using BCI3 in dichloromethane provided the final chelator in good yield. The acid-base properties of catTHC in aqueous solution and the affinity of the ligand towards iron(III) were investigated at variable pH and in the presence of iron(III) using spectroscopic methods. The hexadentate ligand forms a 1:1 complex with iron(III) whose stability constant was determined by competition with EDTA. The values obtained for the stability constant and pFe(3+) are log beta(110) = 36.70 and pFe(3+) = 26.7.

Abstract
A novel technique for the creation of metal-organic framework (MOF) films based on soft-imprinting and their use as gas sensors was developed. The microporous MOF material [Zn-2(bpdc)(2)(bpee)] (bpdc = 4,4'-biphenyldicarboxylate; bpee = 1,2-bipyridylethene) was synthesized solvothermally and activated by removing the occluded solvent molecules from its inner channels. MOF particles were characterized by powder X-ray diffraction and fluorescence spectroscopy, showing high crystallinity and intense photoluminescence. Scanning electron microscope images revealed that MOF crystals were mainly in the form of microneedles with a high surface-to-volume ratio, which together with the high porosity of the material enhances its interaction with gas molecules. MOF crystals were soft-imprinted into cellulose acetate (CA) films on quartz at different pressures. Atomic force microscope images of soft-imprinted films showed that MOF crystals were partially embedded into the CA. With this procedure, mechanically stable films were created, with crystals protruding from the CA surface and therefore available for incoming gas molecules. The sensing properties of the films were assessed by exposing them to saturated atmospheres of 2,4-dinitrotoluene, which resulted in a substantial quenching of the fluorescence after few seconds. The soft-imprinted MOF films on CA/quartz exhibit good sensing capabilities for the detection of nitroaromatics, which was attributed to the MOF sensitivity and to the novel and more efficient film processing method based on soft-imprinting.

Abstract
We have recently demonstrated that tripodal hexadentate chelators, based on 3-hydroxy-4-pyridinone units, can limit the access of iron to bacteria and have a significant inhibitory effect in the intramacrophagic growth of Mycobacterium avium. The results showed that the chelation of iron is a determinant although not sufficient property for antimicrobial activity. The rhodamine B isothiocyanate labelled chelator (MRH7) exhibited the strongest inhibitory activity and was identified as a lead compound since a dose response effect was observed. Significant inhibition of M. avium growth was achieved at a concentration as low as 1 mu M. To identify key molecular features essential for the biological activity we designed parent hexadentate and bidentate chelators, in which different structural groups are introduced in the molecular framework. Herein, we report the work concerning three novel fluorescent chelators: a hexadentate ligand labelled with 5(6)-carboxytetramethylrhodamine (MRH8) and two 3-hydroxy-4-pyridinone fluorescent bidentate ligands labelled with rhodamine B isothiocyanate (MRB7) and 5(6)-carboxytetramethylrhodamine (MRB8). The results show that all fluorescent chelators are capable of restricting the intramacrophagic growth of M. avium and that the inhibitory effect is dependent on the fluorophore. In fact, for compounds bearing the same fluorophore the results obtained with the hexadentate or bidentate chelator (MRH7/MRB7 or MRH8/MRB8) are identical as long as the appropriate stoichiometric amount of chelator is used. The inhibitory effect of the rhodamine B isothiocyanate labelled compounds (MRH7 and MRB7) is significantly greater than that observed for the other two chelators, thus pointing out the significance of the rhodamine B isothiocyanate molecular fragment.