The oxidation of organic compounds with carbon-carbon double bond with using of molecular oxygen under atmospheric pressure in the presence of polyaniline supported catalyst has been studied. Our purpose was to combine the advantages of supported catalysts and inexpensive oxidant. In our experiments inorganic cobalt(II) salts – cobalt(II) chloride and cobalt(II) acetate – were immobilized on polyaniline matrix. Those catalyst turned out to be efficient and selective for oxidation of unsaturated organic compounds as well as oxidation of hydrocarbons in benzyl position. Oxidation reactions were carried out in relatively mild conditions in presence of molecular oxygen under atmospheric pressure at temperature 333K. Alkenes with terminal carbon-carbon double bonds were selectively oxidized to corresponding epoxides with very high yield and selectivity. Cyclic alkenes were easily oxidized mainly to epoxides. Oxidation of hydrocarbons in benzyl position give ketones as a main products. The yield of the oxidation reaction depends on cobalt compound which was used in polyaniline doping. Due to the fact that amount of cobalt salt immobilized on polyaniline support is critical factor in the oxidation, more detailed comparison of our both catalysts were carried out in testing reaction of dec-1-ene oxidation. In the polymer doping reaction different ratios of cobalt(II) salts and polyaniline were used. Some kind of saturation of polyaniline surface was observed, when concentration of Co(II) reach about 30 mg of Co(II) per gram of sample, after that no further changes were found.

In our research the influence of pH on the properties of crosslinked waxy corn starch modified with acrylic monomers has been studied. These systems are characterized with the ability to absorb and hold a large quantity of water and aqueous solutions. However, due to the presence of the starch granules in their structure they are easily biodegradable. In our study, a number of cross-linked hydrogels based on waxy maize starch and acrylic acid derivatives were synthesized. Acrylic acid used in reactions was partially neutralized with NaOH. N,N\'-methylenebisacrylamide was used as the cross-linking agent. A series of polymers with different content of ionized carboxyl groups were obtained. These polymers were used for further study of their properties, in particular swelling properties and concentration of carboxyl and carboxylate groups. Presence of those hydrophilic groups is largely responsible for the high affinity of the polymer to water. A significant increase in the gelation time with increasing of sodium acrylate content was observed. As expected, the increase in content of carboxylate groups with an increase of neutralization degree of acrylic acid used in the synthesis of the polymer was observed, while content of unionized carboxyl groups decreased. A series of experiments were carried out to determine the effect of pH on the absorption of hydrogels. It should be noted that the amount of absorbed water is generally affected by the ionic strength of the solution, therefore, to compare the individual results of swelling in the range of pH 5.0-9.0 experiments were performed in buffers solution with the same ionic strength. High rate of absorption of aqueous solutions was observed. Approximately 60-70% of the maximum value is attained during the first 10 minutes. It was found that when pH of solution increases, amount of water absorbed per gram of hydrogel increases. Hydrogel composition also has a significant impact on the swelling properties of hydrogel. A minimum of water absorption was observed for polymers in which the ratio of acrylic acid to sodium acrylate was 1:1.

Conformationally restricted α -amino acids are valuable tools for studying the spatial requirements for receptor affinity and biological activity of natural amino acids. In this context, proline analogues possessing the characteristics of other amino acids (so-called chimeras) are of current interest. In addition, the conformationally rigid pyrrolidine fragment in their molecules stabilizes the substituents attached, moreover, in a certain spatial orientation with respect to each other. As a result, the conformational mobility of the entire molecule is restricted, thus enhancing the interaction between the pyrrolidine ligand and the active site of a protein target, as compared to an acyclic analogue. In a past decades, several analogues of proline chimeras with different stereochemistry and functionality at C-3 position have been synthesised (e.g Pro-Lys, Pro-Phe, Pro-Thr chimeras). While these analogues have proved useful for inducing specific constraints into amino acids and peptides, their structures do not permit additional derivatisation; a trait that is often required in drug discovery and lead optimisation. Polyfunctional proline-amino acid chimera may overcome these drawbacks. Our concept for developing such polyfunctional proline-amino acid chimeras employs the highly stereoselective intramolecular Michael reaction as a key step. Polysubstituted oxoprolines were prepared in two steps in high diastereomeric purity as all-trans stereoisomers. The required optically pure γ-oxo-α-aminoacids were prepared by reversible aza-Michael addition and/or multicomponent Mannich reaction using the crystallisation-induced asymmetric transformation (CIAT). The following acylation with maleic anhydride and highly diastereoselective intramolecular Michael reaction provided desired polysubstituted oxoprolines as single diastereomers.

In the field of synthetic organic chemistry, the dehalogenations are common and interesting reactions. Typical procedures generally use electrochemical, photochemical, and ultrasonic techniques. Within the broad range of conditions for carrying out such reactions, the use of indium is of particular interest because it can be utilized in different solvents as organic media, water or without solvent. Besides, this metal is stable in air and its toxicity is lower compared with to that observed in other metals.^1,2 In the context of contributing to the development of new synthetic methodology in the field of indium chemistry, as a preliminary study, we propose the use of ionic liquid as alternative solvent to carry out dehalogenation reactions. Dehalogenation of aromatics compounds was investigated by a series of reactions under several conditions. Bromobenzene was used as a starting material and due to ionic liquids (IL) have well-known properties as green solvents, we tested this procedure changing the IL.^3,4 The treatment of bromobenzene with [bmim]Cl and [bmim]Br afforded the corresponding dehalogenated derivative in good to excellent yield. However, when using as an alternative others ionic liquids [bmim]PF₆, [bmim]BF₄, [bmpy]F₃CSO₃ and TBAF, reactions did not proceed. In order to ensure the validity of the results shown above for bromobenzene, we proceeded to extend this method for chlorinated and iodinated benzene. Our experimental results indicate that [bmim]Br is the most effective solvent for this reaction. To explore the scope of this dehalogenation reaction, we investigated the behavior of others haloaromatics and haloheteroaromatics systems using indium under [bmim]Br conditions. The yields of dehalogenated products were in moderate to excellent range. In conclusion, we have demonstrated that a reductive system consisting of an indium powder in ionic liquid allows a highly conversion of haloaromatics and haloheteroaromatics compounds. This work was supported by Bicentenario Project PSD-70, Interdisciplinary Project 27/2011, and Research Project 3901-026-81, Chemistry Faculty, Pontificia Universidad Católica de Chile. References 1 Alonso, F.; Beletskaya, I.; Yus, M. Chem. Rev. 2002, 102, 4009-4091. 2 Ranu, B. C.; Dutta, P.; Sarkar, A. J. Chem. Soc., Perkin Trans. I, 1999, 1139-1140. 3 Pavlinac, J.; Zupan, M.; Laali, K.; Stavber, S. Tetrahedron, 2009, 65, 5625-5662. 4 Sowmiah, S.; Srinivasadesikan, V.; Tseng, M-C.; Chu, Y-H. Molecules, 2009, 14, 3780-3813.

Molecularly imprinted polymers (MIPs) are a class of highly cross-linked polymer that can bind certain target compound with high specificity. The polymers are prepared in the presence of the target molecule itself as the template. The template interacts with functional monomers before being cross-linked in polymerization process. The specific binding site complementary to the target analyte is generated upon the removal of the template from the solid polymers. The knowledge of the interactions between the target (in this case, cocaine and benzoylecgonine molecules) and the monomer seems to be very important in the design of this MIPs. For this reason, a computational study of the interactions between cocaine and benzoylecgonine molecules, and methacrylic acid is presented. Different position for the interactions and number of molecules of monomer are considered in this DFT study. The effect of solvent is also analyzed.

Benzimidazole derivatives belong to a crucial structural design that is seen in many pharmaceutically and biologically interesting molecules. Benzimidazoles have shown potential for application in a variety of pharmacological targets. They have been intensively used in medicinal chemistry as drugs such as antihistaminic, antimalarial action, antiprotozoal activity, antibacterial activity, antiulcerative, antihelmentic, antipsychotic etc. The preparation and investigation of nitrogen heterocycles is one of our main projects. We have already developed some procedures to gain access to diverse structures of benzimidazoles. It has been reported that 2-(Substituted pyridynyl) benzimidazole possess anti-inflammatory activity. At the same time alkyl or aryl substitution at second position of benzimidazole is not yet reported, which may possess same activity as that of benzimidazole substituted with pyridynyl. The series of new 2-(Substituted alkyl and aryl pyridynyl) benzimidazole derivatives have been prepared. In this case, corresponding eight orthophenylenediamine (opd) derivatives were prepared and these results prompted us to extend this methodology for similar synthesis of benzimidazole derivatives. Compounds 1 (5-Ethoxy, 1H-Benzimidazole), 7 (2-(5-Ethoxy-1H-benzoimidazol-2-yl)-Ethanol) and 8 (2-(5-Ethoxy-1H-benzoimidazol-2-yl)-Methanol) were exclusively isolated and characterized with other five derivatives. It was thought that preparing such derivatives as 2-substituted benzimidazoles would probably result in compounds of having high biological activity like anti-inflammatory with low toxicity toward many diseases and hence tested for their possible anti-inflammatory activity. Carrageenan induced rat paw edema is the most widely used, primary test to screen inflammation which measures the ability of the compounds to reduce local edema induced in the rat paw by carrageenan. Hence anti-inflammatory activity was evaluated by using carrageenan induced rat paw edema method. Most of the obtained compounds exhibit anti-inflammatory activity, especially compound Compounds 1 (5-Ethoxy, 1H-Benzimidazole), 7 (2-(5-Ethoxy-1H-benzoimidazol-2-yl)-Ethanol) and 8 (2-(5-Ethoxy-1H-benzoimidazol-2-yl)-Methanol) showed significant activity when compared with that of standard drug ibuprofen.

A general and efficient protocol is described for one pot three component intramolecular cyclization of anilines, aldehydes and malononitrile in neat water within very shorter reaction times and higher yield. Titled compounds synthesized under both microwave irradiation and classical heating for comparison purposes. The catalytic activity of L-proline in these reactions was tested over a set of aldehydes and amines, demonstrating that it is reactive toward a variety of functionalities. The role of water in reaction mechanism also demonstrated. The use of a monomode oven allowed an accurate consideration of the temperature distribution in the microwave reaction vessel, which revealed a very strong and unexpected thermal heterogeneity.

A novel 6,8-dibromo-7-hydroxychromone-3-carboxaldehyde (4) was prepared from the Vilsemier-Haack formylation of 3,5-dibromo-2,4-dihydroxyacetophenone. The chemical reactivity of carboxaldehyde 4 was studied towards some hydrazine derivatives under different reaction conditions. 1,3,4-Thiadiazol-2-ylchromone derivative 10 was also prepared. The chemical behavior of carboxaldehyde 4 was studied towards hydroxylmine hydrochloride under different reaction conditions to produce compounds 11-14. The reaction mechanism and mass spectrometry for some compounds were also reported.

In the present study, a series of new N-alkyl-N-(piperidin-1-yl)benzenesulfonamide (1a-f) and N-aryl/alkyl substitued-2-[(phenylsulfonyl)(piperidin-1-yl)amino]acetamide (3a-n) derivatives were synthesized. These derivatives were prepared by reacting 1-amino piperidine with benzene sulfonyl chloride to afford parent compound N-(piperidin-1-yl)benzenesulfonamide (1), followed by substitution at nitrogen with different electrophilic reagents in the presence of sodium hydride to give a series of derivatives 1a-f and 3a-n. The structures of the synthesized compounds were confirmed based on ¹H-NMR, IR and mass spectral data. The synthesized compounds were screened against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes and almost all the compounds exhibited promising activity.

Pyrylium salts belong to a very important class of cationic organic molecules that have trivalent oxygen in a six membered aromatic ring.[1] Numerous references are available for this kind of compounds such as crystallographic and structural studies[2] and specially their good absorption, fluorescence, and electron acceptor behavior. The pyrylium salts have been exploited to design sensors for anion,[3] amines, amino acids and chameleon labels for quantifying proteins[4] among others. It is known that the anion nature, in particular, BF₄^- has a significant influence on the reactivity of Pyrylium salts. With the aim to demonstrate the presence of this anion by using ¹⁹F-NMR we have observed peculiar results. In this context, we have studied the small but significant variations on chemical shifts from lightly to heavily modified tri-arylpyrylium cations 1-5. We thank the AECID (Projects A/023577/09 and A/030422/10) and the \'Junta de Andalucía\' (FQM 142 and Project P09-AGR-4597) for financial support. [1] Manoj, N.; Ajayakumar, G.; Gopidas, K. R.; Suresh, C. H., J. Phys. Chem. A, 2006, 110 (39), 11338-45. [2] Turowska-Tyrk, I.; Krygowski, T. M. J. Mol. Struct. 1991, 263, 235-45. [3] García-Acosta, B.; García, F.; García, J.M.; Martínez-Máñez, R.; Sancenón, F.; San-José, N.; Soto, J. Org. Lett. 9, 13, 2007, 2429-32. [4] Wetzl, B.K.; Yarmoluk, S.M.; Craig, D.M.; Wolfbeis, O.S., Angew. Chem. Int. Ed. 2004, 43, 5400-02.