Análisis del impacto ambiental de la línea de intervención Resa Urbano del departamento para la prosperidad social de la República de Colombia en la ciudad de Tunja

El objetivo principal de esta tesis es determinar el impacto ambiental de la línea de intervención ReSA Urbano de la Ciudad de Tunja con la finalidad de proponer mejoras ambientales en el proceso. ReSA hace parte del programa de Seguridad Alimentaria y Nutrición del Departamento para la Prosperidad Social (DPS) de la República de Colombia. Para establecer el impacto ambiental se utiliza la metodología del Análisis del Ciclo de Vida (ACV).The main objective of this thesis is to determine the environmental impact of the intervention line ReSA Urban Tunja in order to propose environmental improvements in the process, ReSA program is part of the Food and Nutrition Security program from the Social Prosperity Department (SPD) from Colombian Republic. To establish the environmental impact analysis methodology of Life Cycle Analysis (LCA) is used. The paper is divided into four chapters.Magíster en Gestión AmbientalMaestrí

Halogen-bonded solvates of tetrahaloethynyl cavitands

The formation and structures of halogen-bonded solvates of three different tetrahaloethynyl cavitands with acetone, chloroform, acetonitrile, DMF and DMSO were prepared and investigated. The inclusion and host-guest behaviour of the resorcinarene cavitands was found to be highly dependent on the flexibility of the ethylene-bridging unit

Host-guest complexes of C-propyl-2-bromoresorcinarene with aromatic N-oxides\u3csup\u3e*\u3c/sup\u3e

The host-guest complexes of C-propyl-2-bromoresorcinarene with pyridine N-oxide, 3-methylpyridine N-oxide, quinoline N-oxide and isoquinoline N-oxide are studied using single crystal X-ray crystallography and 1H NMR spectroscopy. The C-propyl-2-bromoresorcinarene forms endo-complexes with the aromatic N-oxides in the solid-state when crystallised from either methanol or acetone. In solution, the endo-complexes were observed only in methanol-d4. In DMSO the solvent itself is a good guest, and crystallisation provides only solvate endo-complexes. The C-propyl-2-bromoresorcinarene shows remarkable flexibility when crystallised from either methanol or acetone, and packs into one-dimensional self-included chains. Of special note, crystallising C-propyl-2-bromoresorcinarene with 3-methylpyridine N-oxide from acetone results in a 2:2 dimeric capsular assembly organised through both C−H···πhost and N−O···(H−O)host interactions

Sharing the salt bowl: counterion identity drives N-alkyl resorcinarene affinity for pyrophosphate in water

N-Alkyl ammonium resorcinarene chloride receptors, NARX4, have been shown to act as high-sensitivity detectors of pyrophosphate (PPi), a biomarker of disease, in aqueous media through the chloride-to-PPi exchange [NAR(Cl)4 to NARPPi]. The nature of the anion of the macrocyclic NARX4 (X = Cl−, Br−, triflate OTf−) receptor greatly influences the PPi-affinity in aqueous media. The binding affinity for [NAR (Cl)4] is 3.61 × 105 M−1, while the NAR (Br)4 and NAR (OTf)4 show stronger binding of 5.30 × 105 M−1, and 6.10 × 105 M−1, respectively. The effects of upper rim ammonium cation, –N+H2R substituents (R = 3-hydroxypropyl, cyclohexyl, benzyl, or napththalen-1-ylmethyl), of the macrocyclic resorcinarene hosts have also been evaluated. The highest affinity was obtained using 3-hydroxypropyl groups due to the additional hydrogen bonds and the naphthyl upper-rim group that provides a larger hydrophobic surface area and favorable stacking interaction (i.e., π–π and CH–π). We note that two PPi molecules can bind to the more selective receptors through an additional interaction with the lower rim hydroxyls, making the resorcinarene a divalent binder. Comparing PPi with other phosphate anions (PO43−, AMP, ADP, and ATP) shows that the receptors are more selective for PPi due to the size and charge complementarity. Experimental (1H, 31P NMR, and isothermal titration calorimetry), and computational analyses support the reported trends for PPi selectivity even in highly competing aqueous media

Bamboo-like Chained Cavities and Other Halogen-Bonded Complexes from Tetrahaloethynyl Cavitands with Simple Ditopic Halogen Bond Acceptors

Halogen bonding provides a useful complement to hydrogen bonding and metal-coordination as a tool for organizing supramolecular systems. Resorcinarenes, tetrameric bowl-shaped cavitands, have been previously shown to function as efficient scaffolds for generating dimeric capsules in both solution and solid-phase, and complicated one-, two-, and three-dimensional frameworks in the solid phase. Tetrahaloethynyl resorcinarenes (bromide and iodide) position the halogen atoms in a very promising crown-like orientation for acting as organizing halogen-bond donors to help build capsules and higher-order networks. Symmetric divalent halogen bond acceptors including bipyridines, 1,4-dioxane, and 1,4-diazabicyclo[2.2.2]octane are very promising halogen bond accepting partners for creating these systems. This report describes the complex structures arising from combining these various systems including self-included dimers, herringbone-packed architectures enclosing medium (186 Å3) cavities, and a very intriguing bamboo-like one-dimensional rod with large (683 Å3) cavities between adjacent dimeric units. These various structures, all organized through host-host, host-acceptor, and host-solvent interactions highlight the emergent complexity of these types of complexes. As halogen bonds are weaker than hydrogen-bonds, the resulting architectures are harder to predict, and these results provide additional insight into the parameters requiring consideration when designing crystalline supramolecular systems using halogen-bonds as the core organizing principle

Naphthalene-functionalized resorcinarene as selective, fluorescent self-quenching sensor for kynurenic acid†

Kynurenic acid is a by-product of tryptophan metabolism in humans, with abnormal levels indicative of disease. There is a need for water-soluble receptors that selectively bind kynurenic acid, allowing for detection and quantification. We report here the high-affinity binding of kynurenic acid in aqueous media to a resorcinarene salt receptor decorated with four flexible naphthalene groups at the upper rim. Experimental results from 1H NMR, isothermal titration calorimetry, and electronic absorption and fluorescence spectroscopies all support high-affinity binding and selectivity for kynurenic acid over tryptophan. The measured binding constant (K = 1.46 ± 0.21 × 105 M−1) is one order of magnitude larger than that observed with other resorcinarene receptors. The present host–guest system can be employed for sensory recognition of kynurenic acid. Computational studies reveal the key role of a series of cooperative attractive intra- and inter-molecular interactions contributing to an optimal binding process in this system

Crystalline cyclophane-protein cage frameworks

open10siCyclophanes are macrocyclic supramolecular hosts famous for their ability to bind atomic or molecular guests via noncovalent interactions within their well-defined cavities. In a similar way, porous crystalline networks, such as metal organic frameworks, can create microenvironments that enable controlled guest binding in the solid state. Both types of materials often consist of synthetic components, and they have been developed within separate research fields. Moreover, the use of biomolecules as their structural units has remained elusive. Here, we have synthesized a library of organic cyclophanes and studied their electrostatic self-assembly with biological metal-binding protein cages (ferritins) into ordered structures. We show that cationic pillar[S]arenes and ferritin cages form biohybrid cocrystals with an open protein network structure. Our cyclophane-protein cage frameworks bridge the gap between molecular frameworks and colloidal nanoparticle crystals and combine the versatility of synthetic supramolecular hosts with the highly selective recognition properties of biomolecules. Such host-guest materials are interesting for porous material applications, including water remediation and heterogeneous catalysis.openBeyeh N.K.; Nonappa; Liljestrom V.; Mikkila J.; Korpi A.; Bochicchio D.; Pavan G.M.; Ikkala O.; Ras R.H.A.; Kostiainen M.A.Beyeh, N. K.; Nonappa, ; Liljestrom, V.; Mikkila, J.; Korpi, A.; Bochicchio, D.; Pavan, G. M.; Ikkala, O.; Ras, R. H. A.; Kostiainen, M. A

Investigation of activation energies for dissociation of host-guest complexes in the gas phase using low-energy collision induced dissociation

International audienceA low-energy collision induced dissociation CID (low-energy CID) approach that can determine both activation energy and activation entropy has been used to evaluate gas-phase binding energies of host-guest (H-G) complexes of a heteroditopic hemicryptophane cage host (Zn(II)@1) with a series of biologically-relevant guests. In order to use this approach, preliminary calibration of the effective temperature of ions undergoing resonance excitation is required. This was accomplished by employing blackbody infrared radiative dissociation (BIRD) which allows direct measurement of activation parameters. Activation energies and pre-exponential factors were evaluated for more than 10 host-guest (H-G) complexes via the use of low-energy CID. The relatively long residence time of the ions inside the linear ion trap (maximum of 60 s) allowed the study of dissociations with rates below 1 s-1. This possibility, along with the large size of the investigated ions, ensures the fulfilment of rapid energy exchange (REX) conditions, and as a consequence, accurate application of the Arrhenius equation. Compared to the BIRD technique, low-energy CID allows access to higher effective temperatures, thereby permitting one to probe more endothermic decomposition pathways. Based on the measured activation parameters, guests bearing a phosphate (-OPO3 2-) functional group were found to bind more strongly with the encapsulating cage than those having a sulfonate (-SO3-) group; however, the latter ones make stronger bonds than those with a carboxylate (-CO2-) group. In addition, it was observed that the presence of trimethylammonium (-N(CH3)3 +) or phenyl groups in the guest's structure, improves the strength of host-guest interactions. The use of this technique is very straightforward, and it does not require any instrumental modifications. Thus, it can be applied to other H-G chemistry studies where comparison of bond dissociation energies is of paramount importance