Rapidity of clinical response to adalimumab and improvement of quality of life in luminal Crohn's disease: RAPIDA study.

OBJECTIVE: No studies evaluating the rapidity of response to biological therapies are available for Crohn's disease (CD). The aim of this study was to evaluate rapidity of onset of clinical response and impact on quality of life (QoL) of adalimumab therapy in adult anti-TNF-naïve patients with moderately-to-severely active CD. PATIENTS AND METHODS: RAPIDA was an open-label, single-arm, prospective, multicenter clinical trial. Adult patients with moderately-to-severely active luminal CD, anti-TNF-naïve, and unresponsive to conventional therapy were treated with adalimumab. Clinical disease activity, QoL and inflammatory biomarkers were measured at day 4, and weeks 1, 2, 4, and 12 after treatment initiation. RESULTS: Eighty-six patients were included in the intention-to-treat (ITT) analyses. Clinical disease activity was reduced from a median of 9.0 points to 6.0 points at day 4. Clinical response (≥ 3-point reduction in the Harvey-Bradshaw Index, HBI) was achieved by 61.6% (d4) and 75.6% (w1) of patients in the ITT population (median 2.5 days) and with non-responder imputation (NRI), by 55.8% and 53.4%, respectively. The proportion of patients in clinical remission (HBI<5) at weeks 2 and 4 in the ITT population was 54.7% and 62.8%, respectively (median 7.0 days), and 38.4% and 45.3% in the NRI population. All QoL scores significantly improved and inflammatory biomarkers significantly decreased from day 4 onwards (p<0.0001). CONCLUSION: Rapid clinical response and remission, improvement in QoL and fatigue, and a reduction of inflammatory biomarkers were achieved with adalimumab as early as day 4 in adult anti-TNF-naïve patients with moderately-to-severely active CD.

On-Demand Hydrophobic Drug Release Based on Microwave-Responsive Graphene Hydrogel Scaffolds.

Electromagnetically driven drug delivery systems stand out among stimulus-responsive materials due to their ability to release cargo on demand by remote stimulation, such as light, near infrared (NIR) or microwave (MW) radiation. MW-responsive soft materials, such as hydrogels, generally operate at 2.45 GHz frequencies, which usually involves rapid overheating of the scaffold and may affect tissue surrounding the target location. In contrast, 915 MHz MW penetrate deeper tissues and are less prone to induce rapid overheating. In order to circumvent these limitations, we present here for the first time a graphene-based hydrogel that is responsive to MW irradiation of ν=915 MHz. This system is a candidate soft scaffold to deliver a model hydrophobic drug. The graphene present in the hydrogel acts as a heat-sink and avoids overheating of the scaffold upon MW irradiation. In addition, the microwave trigger stimulates the in vitro delivery of the model drug, thus suggesting a remote and deep-penetrating means to deliver a drug from a delivery reservoir. Moreover, the MW-triggered release of drug was observed to be enhanced under acidic conditions, where the swelling state is maximum due to the swelling-induced pH-responsiveness of the hydrogel. The hybrid composite described here is a harmless means to deliver remotely a hydrophobic drug on demand with a MW source of 915 MHz. Potential use in biomedical applications were evaluated by cytotoxicity tests.

Stimuli-responsive graphene-based hydrogel driven by disruption of triazine hydrophobic interactions.

The study reported here concerns the preparation of a novel graphene-diaminotriazine (G-DAT) nanocomposite hydrogel for application in the drug delivery field. The hybrid nature of this material is founded on two key elements: the presence of the DAT backbone induced the formation of hydrophobic regions that allowed efficient loading of a series of drugs of increasing hydrophobicity (Metronidazole, Benzocaine, Ibuprofen, Naproxen and Imipramine), while simultaneously endowing swelling-induced pH-responsiveness to the hydrogel. Additionally, the incorporation of graphene was found to interfere with these hydrophobic domains through favourable non-covalent interactions, thus leading to the partial disruption of these aggregates. As a consequence, graphene facilitated and enhanced the release of model hydrophobic drug Imipramine in a synergistic manner with the pH trigger, and increased the swelling capacities and improved mechanical performance. This hybrid hydrogel can therefore be envisaged as a proof-of-concept system for the release of hydrophobic compounds in the field of drug delivery.

Physically Cross-Linked Hydrogel Based on Phenyl-1,3,5-triazine: Soft Scaffold with Aggregation-Induced Emission.

A phenyltriazine compound has been used for the first time as a monomer in the construction of a hydrogel. This physically cross-linked soft material showed blue fluorescence when excited under UV-light. Polymer formation and intermolecular H-bonds arising from triazine moieties operate as aggregation-induced emission (AIE) mechanisms. The combination of soft materials and AIE properties expands the applications of these materials. As a proof of concept, two luminescent dyes have been incorporated into the hydrogel to produce a white-light-emitting material.

Triazine-Carbon Nanotubes: New Platforms for the Design of Flavin Receptors.

The synthesis of functionalised carbon nanotubes as receptors for riboflavin (RBF) is reported. Carbon nanotubes, both single-walled and multi-walled, have been functionalised with 1,3,5-triazines and p-tolyl chains by aryl radical addition under microwave irradiation and the derivatives have been fully characterised by using a range of techniques. The interactions between riboflavin and the hybrids were analysed by using fluorescence and UV/Vis spectroscopic techniques. The results show that the attached functional groups minimise the π-π stacking interactions between riboflavin and the nanotube walls. Comparison of p-tolyl groups with the triazine groups shows that the latter have stronger interactions with riboflavin because of the presence of hydrogen bonds. Moreover, the triazine derivatives follow the Stern-Volmer relationship and show a high association constant with riboflavin. In this way, artificial receptors in catalytic processes could be designed through specific control of the interaction between functionalised carbon nanotubes and riboflavin.

Química Farmacéutica de las Acilaminometilpiridinas / Pharmaceutical Chemistry of Acylaminomethylpyridines

Se han sintetizado una nueva familia de depresores del Sistema Nervioso Central, basado en un sistema denominado actualmente la 'utilización de fragmentos'. A uno de los fármacos obtenidos por este procedimiento la OMS le asignó el nombre de picobenzida. Al tratarse de una benzamida sustituida se prepararon análogos modificando los sustituyentes del anillo aromático y se llevó a cabo un estudio QSAR de la serie, que condujo a la optimización de la misma. Un ensayo para modificar el anillo de piridina condujo a una nueva reacción de dimerización para esta clase de compuestos (AU)

A new family of central nervous system depressants has been synthesized, applying the methodology now known as the 'use of fragments'. One of the drugs produced by this process was assigned the name picobencide by WHO. Being a substituted benzamide, analogues were prepared modifying the substituents of the aromatic ring. A QSAR study was carried out which led to the optimization of the series. A test to modify the pyridine ring led to a new dimerization reaction of this kind of compounds (AU)

Anion-dependent self-assembly of silver(I) and diaminotriazines to coordination polymers: non-covalent bonds and role interchange between silver and hydrogen bonds.

New coordination polymers have been obtained by the self-assembly of silver salts AgX (X = BF 4, PF 6, CF 3SO 3) and 2,4-diamino-6-R-1,3,5-triazines L (R = phenyl and p-tolyl) of formulas AgLX ( 1- 6). A complex of different stoichiometry, [Ag 3L 2(H 2O)(acetone) 2](BF 4) 3, 7 (R = phenyl), has also been synthesized. The three-dimensional structures of five compounds have been determined by X-ray diffraction studies. For the AgLX complexes, when X = BF 4 and R = phenyl or p-tolyl, chiral chains with alternating Ag and L are formed. The chains are cross-linked by the counteranions in a three-dimensional fashion through hydrogen bonds and weak Ag...F interactions giving rise to a structure with solvent-filled channels. Different and more compact structures have been found when the counteranion is CF 3SO 3 (OTf). When R = phenyl, sheets are formed which consist of [Ag 2(OTf) 2L 2] units with double triflate bridges and which contain columns of pi-pi stacked arenes. Hydrogen bonds connect the sheets. When AgOTf is used and R is p-tolyl, a different and unusual ladderlike structure is obtained in which the rungs are double asymmetric bridges consisting of the triflate groups bonded to Ag in kappa (2) O,mu 2- O and kappa (1) O,mu 2- O fashion. The ladders are parallel to each other and are mutually linked by N-H...N hydrogen bonds to give a 3D architecture. A very similar ladderlike structure has been found for 7 but with a water molecule and a BF 4 (-) group acting as bridges. The role played by the hydrogen bonds in complex 6 to form the 3-D structure is played in 7 by [Ag(acetone) 2] fragments. The noncovalent interactions play an important role in the different solid-state 3D structures. The behavior of the new derivatives in solution has also been analyzed. A new species has been detected at low temperatures, and this exhibits restricted rotation of the phenyl ring.

Microwave-assisted reactions in heterocyclic compounds with applications in medicinal and supramolecular chemistry.

Microwave irradiation has been successfully applied in organic chemistry. Spectacular accelerations, higher yields under milder reaction conditions and higher product purities have all been reported. Indeed, a number of authors have described success in reactions that do not occur under conventional heating and modifications in selectivity (chemo-, regio- and stereoselectivity) have even been reported. Recent advances in microwave-assisted combinatorial chemistry include high-speed solid-phase and polymer-supported organic synthesis, rapid parallel synthesis of compound libraries, and library generation by automated sequential microwave irradiation. In addition, new instrumentation for high-throughput microwave-assisted synthesis continues to be developed at a steady pace. The impressive speed combined with the unmatched control over reaction parameters justifies the growing interest in this application of microwave heating. In this review we highlight our recent advances in this area, with a particular emphasis on cycloaddition reactions of heterocyclic compounds both with and without supports, applications in supramolecular chemistry and the reproducibility and scalability of organic reactions involving the use of microwave irradiation techniques.

Anticancer drug discovery and pharmaceutical chemistry: a history.

There are several procedures for the chemical discovery and design of new drugs from the point of view of the pharmaceutical or medicinal chemistry. They range from classical methods to the very new ones, such as molecular modeling or high throughput screening. In this review, we will consider some historical approaches based on the screening of natural products, the chances for luck, the systematic screening of new chemical entities and serendipity. Another group comprises rational design, as in the case of metabolic pathways, conformation versus configuration and, finally, a brief description on available new targets to be carried out. In each approach, the structure of some examples of clinical interest will be shown.

Synthesis, structural determination and dynamic behavior of 2-chloro-4,6-bis(pyrazolylamino)-1,3,5-triazines.

A series of 2-chloro-4,6-bis(pyrazolylamino)-1,3,5-triazines with applications in crystal engineering have been prepared. At low temperature, the presence of two or three isomers has been detected and these assigned to 4,6-diamino-1,3,5-triazine structures on the basis of comparison with model compounds. 2D-Exchange spectroscopy studies in various solvents and at different temperatures have been used to determine the equilibrium constants and the activation free energies of the restricted rotation about the amino-triazine bond. A plot of the activation free energy versus temperature showed a good linear correlation and confirmed that the same process is present in all of the compounds under investigation. Comparison with model compounds also confirmed both the occurrence of the restricted rotation and the 4,6-diamino-1,3,5-triazine tautomerism for triazines 1-4 in solution. The structure of compound 1 has been determined in the solid state by X-ray crystallography and consists ofa 4,6-diamino- 1,3,5-triazine structure stabilized by intra and intermolecular hydrogen bonds.

Enhancing stereochemical diversity by means of microwave irradiation in the absence of solvent: synthesis of highly substituted nitroproline esters via 1,3-dipolar reactions.

Microwave irradiation induces the 1,3-dipolar cycloaddition of imines derived from alpha-aminoesters with beta-nitrostyrenes in the absence of solvent within 10-15 min. The reaction proceeds to give yields in the range 81-86% and three isomeric pyrrolidines are obtained in the cycloaddition. Consequently, the use of three imines and two beta-nitrostyrenes gives rise to a library of 18 nitroproline esters. The use of classical heating with longer reaction times (24 h) gives lower yields of products (below 50%) and only two stereoisomers can be detected in each reaction.