The hydantoin moiety occurring in various biologically active compounds represents a pharmaceutical importance most notably known due to their antimicrobial, anticancer and anticonvulsant activity^1,2. The observed activities usually do not arise from the heterocycle itself but from the different ligands that have been attached to it, especially in the position C5. This led us to prepare a series of the novel structural analogues with varying alkenyl substitution patterns on C5. In the multicomponent reaction under Bucherer-Bergs conditions, construction of 5-(alk-3-enyl)-hydantoins were made in good yields starting from unsaturated aldehydes, ketones and β-ketoesters. Some of them were substituted with alkyl groups at N3 position via selective N-alkylation reaction by reacting alkyl halides in the presence of KOH and methanol as a solvent. When allyl-β-ketoesters were used for the synthesis of hydantoins an unexpected decarboxylation were observed. Decarboxylation was not observed only when 2-allyl-ethylacetoacetate was used as the substrates while in other cases fully decarboxylated products were obtained. All alkenyl hydantoins were characterized by elemental analyzes, FTIR, ¹H and ¹³C NMR spectroscopy. This alkenyl hydantoins could serve as useful precursors for further modification, especially for the synthesis of bicyclic hydantoins. Moreover, substituted hydantoins are important building blocks for the synthesis of nonnatural amino acids. 1. J. C. Thenmozhiyal, P. T. Wong, W. Chui, J. Med. Chem., 47 (2004) 1527 2. A. Volonterio, C. R. de Arellano, M. Zanda, J. Org. Chem., 70 (2004) 2161

Chloramphenicol (CAP) is a broad-spectrum bacteriostatic antibiotic commonly used in veterinary medicine and active against both Gram-positive and Gram-negative bacteria. However, toxic effects in humans such as Grey syndrome, bone narrow suppression, and fatal aplastic anaemia have been described. As a consequence, the use of CAP in foodstuffs has been banned within European Union (EU) since 1994 and no maximum residue limit (MRL) has been established in animal-derived foods. CAP belongs to the amphenicol family of antibacterial agents, that also includes thiamphenicol (TAP) and florphenicol (FLP), approved for use in all food-producing animals. For TAP and FF, maximum residue limits have been established in different matrices for all food producing species. Although LC–MS is the most widely used method for routine determination of amphenicols, in the analysis of real samples with complex matrices it usually implies previous clean-up steps using common solid-phase extraction (SPE) procedures. The main drawback of this extraction technique is the lack of selectivity of the sorbents which requires the optimisation of the extraction and clean-up of target analytes, including column conditioning, sample loading, washing and elution. Molecularly imprinted polymers (MIP) are synthetic materials with recognition sites that specifically bind target molecules in mixtures with other compounds. MIP sorbents, which imitate natural recognition, are capable of meeting the demands of SPE. The aim of the present work is to test the suitability of chloramphenicol for being used as template molecule in the design of molecularly imprinted polymers for amphenicol extraction. Precipitation polymerisation has been used and MIP were tested and optimized for the solid-phase extraction (MISPE) of the group of three, structurally related amphenicols. Recoveries were calculated using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The applicability of these polymers as sorbents for the extraction of amphenicols in milk has been tested.

Application of Vilsmeier–Haack reaction on 4,6-diacetylresorcinol (1) leads to the formation of 4,6-dioxo-4H,6H-pyrano[3,2-g]chromene-3,7-dicarboxaldehyde (2) in good yield. The dicarboxaldehyde 2 was condensed with some carbon and nitrogen nucleophiles. Some aliphatic and aromatic Schiff basesof 4,6-diacetylresorcinol (1)were subjected toVilsmeier–Haack reagent to afford4,6-bis(alkyl/arylimino)-4H,6H-pyrano[3,2-g]chromene-3,7-dicarbaldehydes 10, 14 and 15. Wherever, treatment of some bis-hydrazones of 4,6-diacetylresorcinol 16-19 with Vilsmeier–Haack reagent afforded the corresponding 4,6-bis(pyrazole-3-yl-4-carboxaldehye)resorcinols 20 and 21 which underwent oxidation with iodine to yield fused polyheterocyclic systems 22 and 23, respectively.

A new class of monophosphine ligands has been prepared from naturally chirality renewable source, 1,4 :3,6-dianhydrohexitol compounds, via a nucleophilic substitution process or a hydrophosphination reaction involving microwave activation. These ligands have been evaluated for the rhodium-catalyzed enantioselective hydrogenation of olefins giving good conversion and enantioselectivity up to 95% and 96% ee, respectively.

Camellias have been used in oriental ethnomedicine and appears very promising for pharmaceutical exploitation since modern science has made it possible to specify their potencial medical significance with antimicrobial, antioxidant, anti-allergic, antiviral and skin healing properties. In the present study oils obtained from seeds of several Camellia species were studied for their antimicrobial activities using clinically isolated bacterial and yeast strains. All the oils evidenced antimicrobial activity, and showed different selectivity and MICs for each microorganism tested. Obtained results indicate that the tested Camellia oils acted best in relation to Gram (-) bacteria than Gram (+). The data obtained in the in vitro models clearly establish the antimicrobial potency of all Camellia oils.

Atom-based bilinear indices and linear discriminant analysis (LDA) are used to discover novel trypanosomicidal compounds. The obtained LDA-based quantitative structure-activity relationship (QSAR) models, using non-stochastic and stochastic indices, provide accuracies of 89.02% (85.11%) and 89.60% (88.30%) of the chemicals in the training (test) sets, respectively. Later, both models were applied to the virtual screening of 18 in house synthesized compounds to find new pro-lead antitrypanosomal agents. The in vitro antitrypanosomal activity of this set against epimastigote forms of Trypanosoma cruzi is assayed. Predictions agree with experimental results to a great extent (16/18) of the chemicals. Sixteen compounds show more than 70% of epimastigote inhibition at a concentration 100 µg/mL. In addition, three compounds (CRIS 112, CRIS 140 and CRIS 147) present more than 70% of epimastigote inhibition at a concentration of 10 µg/mL (79.95%, 73.97% and 78.13%, respectively) with low values of cytotoxicity (19.7%, 7.44% and 20.63%, correspondingly).Taking into account all these results, we could say that these three compounds could be optimized in forthcoming works. Even though none of them resulted more active than nifurtimox, the current results constitute a step forward in the search for efficient ways to discover new lead antitrypanosomals.

(2Е,2\'E)-2,2\'-(1,2,4-Thiadiazole-3,5-diyl)bis(3-arylacrylonitriles) were obtained by short-time heating of 3-aryl-2-cyanoprop-2-enethioamides with DMSO–HCl system. Under the same conditions, cyclic thioamides (2-thioxo-1,2-dihydropyridine-3-carbonitrile and quinoxaline-2(1Н)-thione derivatives) reacted to form bis(hetaryl)disulfides in good yields (65-91%). When treated with DMSO–HCl, ethyl 4-(4-chlorophenyl)-5-cyano-2-phenyl-6-thioxo-1,4,5,6-tetrahydropyridine-3-carboxylate afforded a mixture of products of oxidation at sulfur atom and hetero ring. The oxidation of N-aryl-4,6-dimethyl-2-thioxo-1,2-dihydropyridine-3-carboxamides leads to isothiazolo[5,4-b]pyridines. 3-Aryl-2-cyanoprop-2-eneselenoamides reacted with DMSO–HCl to give (2Е,2\'E)-2,2\'-(1,2,4-selenadiazole-3,5-diyl)bis(3-arylacrylonitriles).

DFT (B3LYP) levels of theory using 6-31+G(d,p) basis set have been carried out to investigate the Isomeric structures, energies and properties of LiBr-germacyclopropylidenoids. The theoretical calculations depict that 1 ,3, and 5 have two stationary structures: germanoidal (G), and inverted (I). On the other hand, 2 and 4 have only one stationary structure, germanoidal (G). We also obtained no tetrahedral (T) structure as a minimum for all of the germacyclopropylidenoids. Inverted (I) forms are energetically more stable than germanoidal (G) forms for 3 and 5, whereas stability of germanoidal (G) form higher than inverted (I) form for 1. Moreover, natural bond orbitals (NBO), frontier molecular orbitals (FMO), and molecular electrostatic potential maps (MEP) were achieved in this computational study.

The bis-amide bis-phenoxi N₂O₂ ligand, named as H₄L, was obtained from the 2:1 molar reaction between phenyl salicylate and the diamine 1,3-diaminopropane. The ligand has been characterised by elemental analysis, IR, ¹H and ¹³C NMR spectroscopies, mass spectrometry (ES) and X-ray difraction.

Thiosemicarbanzones have received considerable attention because of their pharmacological activities. They have numerous biological activities, e.g. anticarcinogenic, antibacterial, anti-HIV, anticancer, fungicides, antiviral, antifungal, antitumour, etc[1]. Chandra and co-workers have been reported the synthesis of title compound by the direct reaction 2-pyridine-carbaldehyde and thiosemicarbazide by reflux[2]. A fast and efficient method has been developed for the synthesis of 2-pyridinecarbaldehyde thiosemicarbazone under microwave irradiation. 2-pyridinecarbaldehyde thiosemicarbazone has been synthesized by the reaction of 2-pyridinecarbaldehyde and thiosemicarbazide using microwave irradiation. The preparation of title compound by this way has several advantages including shorter reaction times, cleaner reaction profiles and simple experimental/product isolation procedures[3,4]. Microwave irradiation presents a powerful tool toward organic reactions. This investigation showed that the used method and the results when compared with conventional processes were found to be inexpensive, more friendly and high yielding. This compound has been characterized by FT-IR, ¹H-NMR, ¹³C-NMR techniques and elemental analysis. References 1. Chandra, S.; Kumar, A. Spectrochimica Aceta Part A, 2007, 68, 1410. 2. Chandra, S.; Raizada, S.; Tyagi, M; Sharma, P. K. Spectrochimica Aceta Part A, 2008, 69, 816. 3. Zhang, X-H,; Wang, L-Y,; Zh-X,; Tan, Sh-H,; Zhang, Z-X. dyes and pigments , 2008, 79, 205. 4. Loupy A. Microwaves in organic synthesis. Weinheim: Wiley-VCH; 2002.