Effect of cosurfactant on the supramolecular structure and physicochemical properties of non-ionic biocompatible microemulsions

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Kinetic parameters for thermal decomposition of supramolecular polymers derived from flunixin-meglumine adducts

Meglumine, (2R,3R,4R,5S)-6-methylaminohexane-1,2,3,4,5-pentol, is a carbohydrate derived from sorbitol in which the hydroxyl group in position one is replaced by a methylamine group. It forms binary adducts with substances having carboxyl groups, which have in common the presence of hydrogen bonding as the main force in the stabilization of these species. During melting, adducts of meglumine with flunixin (2-[[2-methyl-3-(trifluoromethyl)phenyl]amino]pyridine-3-carboxylic acid) polymerize or self-assemble in amorphous supramolecular structures with molecular weights around 2.0 x 10(5) kDa. DSC curves, in a first heating, show isomorphic transitions where the last one at 137 A degrees C for the flunixin-meglumine adduct originated the supramolecular amorphous polymers with glass transition around 49.5 A degrees C. The kinetic parameters for the thermal decomposition step of the polymers were determined by the Capela-Ribeiro non-linear isoconversional method. From data for the TG curves in nitrogen atmosphere and heating rates of 5, 10, 15, and 20 A degrees C min(-1), the E (alpha) and B (alpha) terms could be determined and, consequently, the pre-exponential factor, A(alpha), as well as the kinetic model, g(alpha).

Structural aspects, thermal behavior, and stability of a self-assembled supramolecular polymer derived from flunixin-meglumine supramolecular adducts

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A química supramolecular de complexos pirazólicos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Supramolecular assemblies of cis-palladium complexes dominated by C-H center dot center dot center dot Cl interactions

Two cis-related palladium(II) complexes [PdCl(2)(PPh(3))(tu)] (1) and [PdCl(2)(tmen)] (2) {PPh(3) = triphenylphosphine, tu = thiourea, tmen = N,N,N,N-tetramethylethylenediamine} have been synthesized and characterized by elemental analysis, IR and NMR spectroscopies, and single crystal X-ray diffraction. In 1, N-H center dot center dot center dot Cl hydrogen bonds are responsible for the formation of a dimer which connects to an adjacent one through weak C-H center dot center dot center dot Cl interactions, yielding 1D tapes. The crystal packing of compound 2 consists of zigzag ribbons of [PdCl(2)(tmen)] self-assembled by C-H center dot center dot center dot Cl hydrogen bonds which also holds the chains together, giving rise to a 2D layered structure. (C) 2006 Elsevier B.V. All rights reserved.

Dinuclear Azide-Bridged Copper(II) Complex as Building Block for the Assembly of a 2D-Supramolecular Array

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of micelles, microemulsions and other supramolecular aggregates on the hydrolysis of β-lactam antibiotics

A critical revision of the literature was made regarding the stability of β-lactam antibiotics in the presence of surfactants. The factors involved in the drug decomposition were analyzed in the development of the discussion. The analysis has indicated that some organized systems obtained from surfactants can be used to control rates and mechanisms of antibiotic decomposition. These organized systems can also be used to obtain specific information about the drug reactivity in a microenvironment similar to the site of pharmacological effect.

Crystal and supramolecular structures of dysprosium(III) 2-methoxybenzoate tetrahydrate

The compound dysprosium(III) 2-metoxybenzoate, {[Dy(2-MeO-Bz)2μ-(2-MeO-Bz)(H2O)2]2·4H2O}n (2-MeO-Bz = 2- methoxybenzoate), was synthesized from a reaction mixture containing DyCl3 and Na(2-MeO-Bz), and characterized by single-crystal X-ray diffraction. The molecular structure showed dinuclear units in which each Dy(III) ion is coordinated by nine oxygen atoms. The carboxylato groups are bound to the dysprosium centers in two modes: bidentate chelating and tridentate chelating-bridging. Besides this, the occurrence of hydrogen bonds involving a coordinated water molecule and carboxylato groups leads to the formation of helicoidal chains along the crystal lattice, resulting in a supramolecular one-dimensional polymer. 2008 © The Japan Society for Analytical Chemistry.

Kinetic parameters for thermal decomposition of supramolecular polymers derived from diclofenac-meglumine supramolecular adducts

Meglumine is an aminocarbohydrate able to form supramolecular adducts with organic acids. The recognition is based on hydrogen bonds and the structures resulting from the complexation have high solubility in water. This property has been exploited by the pharmaceutical industry in the improvement of existing drugs, and the successful example of this approach involves the poorly soluble non-steroidal anti-inflammatory drugs (NSAIDs). Investigation of the thermal behavior of adduct obtained from meglumine and the NSAID diclofenac revealed that a polymer-like material is formed from the self-assembly of diclofenac-meglumine adducts in the melt. This polymer showed a high molecular weight around 2.0×105kDa. The kinetic parameters for the thermal decomposition step of the polymer were determined by the Capela-Ribeiro non-linear isoconversional method. From data for the TG curves in nitrogen atmosphere and heating rates of 5, 10, 15 and 20°Cmin-1, the Eα and Bα terms could be determined, and consequently the pre-exponential factor, Aα, as well as the kinetic model, g(α). © 2012 Elsevier B.V.

Supramolecular assemblies and magnetic behaviors of the M(II)/p-aminopyridine/malonate (M = Ni, Mn, Cu, Co) systems

The coordination compounds [Ni(μ-mal)(apy)2(H 2O)]·2.8H2O (1), [Mn(μ-mal)(H2O) 2] (2), (apyH)2[Cu(μ-mal)2] (3) and (apyH)2[Co(mal)2(H2O)2] (4) (mal = malonate, apy = p-aminopyridine) have been synthesized and characterized by elemental analysis, vibrational spectroscopy, single crystal X-ray diffraction and magnetometry. With exception of 4, the malonate group acts as bridging ligand leading to the formation of one-dimensional polymeric chains. In compound 1 it was observed the coordination of the p-aminopyridine in the axial positions of the distorted octahedral coordination sphere. The solid-state structure exhibits a high complex 3D network formed by several supramolecular interactions. Magnetic properties were determined for all members of the series and indicate that the materials behave are normal paramagnets, except the Mn polymer 2 which exhibits an antiferromagnetic ground state. © 2013 Elsevier Ltd. All rights reserved.

Síntese e caracterização so polímero supramolecular à base de óleo de semente de mamão (Carica papaya L.) maleinizado-meglumina

Pós-graduação em Química - IQ

Supramolecular arrangements of an organometallic forming nanostructured films

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Regulação microambiental de células epiteliais límbicas corneais de coelho expandidas sobre membrana amniótica humana desepitelizada: ênfase para a organização supramolecular dos maiores biopolímeros extracelulares

Pós-graduação em Cirurgia Veterinária - FCAV

Electropolymerization using binuclear nickel(II) Schiff base complexes bearing N4O4 donors as supramolecular building blocks

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Supramolecular organization-electrical properties relation in nanometric organic films

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)