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A series of task-specific ionic liquids (TSILs) based on glycerylimidazolium cations have been prepared by reaction of 1-chloropropanediol, a compound obtainable from glycerol (a widely available and in-expensive waste product), with the appropriate base (1-H-imidazole, 1,2-dimethylimidazole and 1-methyl-1-H-imidazole). The reaction of 3-(1H-imidazol-1-yl)propane-1,2-diol with chloroalkanes, bromoalkanes and alkyl mesylates gave the corresponding salts which were characterized. The possibility to use these ILs in palladium catalyzed reactions was evaluated, evidencing good catalyst stability and a high recyclability. [ABSTRACT FROM AUTHOR]

8-Hydroxy-6-methyl-5,6,7,8-tetrahydroimidazo[1,2-a]pyridine was formed selectively in high yields from N-(β-methallyl)imidazole by a tandem hydroformylation–cyclization sequence, representing a novel one-pot catalytic synthesis of bicyclic imidazole derivatives. [ABSTRACT FROM AUTHOR]

The enantioselective intramolecular alkylation of substituted imidazoles with enantiomeric excesses up to 98 has been accomplished by rhodium catalyzed C–H bond functionalization with S,S′,R,R′TangPhos as the chiral ligand. [ABSTRACT FROM AUTHOR]

The development of convenient and practical synthetic strategies for constructing bioactive molecules without metal residues is of great interest in organic synthesis. Herein, a metal-free, operationally simple, and scalable electrooxidation-induced three-component cross-coupling method to access 3-thio/selenophosphorylated imidazole derivatives from readily available isothiocyanates/isoselenocyanates, isocyanates, and H-phosphonates is first reported. More than 30 examples have been provided with good to moderate yields. Importantly, the readily accessible compounds could be used as pesticides (wheat anti-locust) with good biocompatibility (5d-stimulated RAW 264.7 macrophages, IL-6 = 5.3 pg mL−1, THF-α = 79.8 pg mL−1), reiterating the importance of the developed electrochemical methodology. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a novel silica gel affinity sorbent with poly(1-vinylimidazole) (PVI) ligand was prepared for the selective removal of endotoxin (LPS) from a water or a BSA solution. The vinyl silane-modified porous silica gel particle SiO2-g-KH570 was used as macromonomer, and PVI was grafted on by heterogeneous graft copolymerization. First, the effect of reaction conditions on the grafted degree (GD) of PVI was investigated in detail by thermogravimetry. Then, the influences of initial LPS concentration, pH and ionic strength of the tested aqueous solutions on LPS removal ability of PVI-g-SiO2 affinity sorbent were studied and compared with those of His-g-SiO2 affinity sorbent. The results showed that maximum LPS removal capacity was obtained with a GD about 2.5wt% and the PVI-g-SiO2 affinity sorbent had better selective removal of LPS compared to His-g-SiO2 affinity sorbent in both water and BSA solution. The affinity mechanism between PVI and LPS is also discussed in this paper. All of our results indicate that PVI is a good ligand for LPS removal. [Copyright &y& Elsevier]

The aim of this paper is to present the synthesis and reactions of thiochroman-4-ones. These compounds are used as precursors for the synthesis of many heterocyclic rings. The reactions of thiochroman-4-ones are subdivided into groups that cover reactions yielding heterocycles such as pyrazoles, imidazoles, thiazoles, indoles, pyridines, pyrimidines, and thiazepines. [ABSTRACT FROM AUTHOR]

Imidazole-based compounds are a series of heterocyclic compounds that exhibit a wide range of biological and pharmaceutical activities. However, those extant syntheses using conventional protocols can be time-costly, require harsh conditions, and result in low yields. As a novel and green technique, sonochemistry has emerged as a promising method for organic synthesis with several advantages over conventional methods, including enhancing reaction rates, improving yields, and reducing the use of hazardous solvents. Contemporarily, a growing body of ultrasound-assisted reactions have been applied in the preparation of imidazole derivatives, which demonstrated greater benefits and provided a new strategy. Herein, we introduce the brief history of sonochemistry and focus on the discussion of the multifarious approaches for the synthesis of imidazole-based compounds under ultrasonic irradiation and its advantages in comparison with conventional protocols, including typical name-reactions and various sorts of catalysts in those reactions. [ABSTRACT FROM AUTHOR]

This paper reports the synthesis and the physical characterization of a new family of chelating ionic liquids carrying a terpyridine fragment suitable for metal extraction. [ABSTRACT FROM AUTHOR]

A simple and convenient approach is developed for the synthesis of the imidazo[1,2-f]phenanthridine framework via post-functionalization of imidazoles obtained through four-component reactions of 1,2-dicarbonyl compounds, anilines, aldehydes and ammonium acetate. The methodology involves palladium-catalyzed direct arylation through sp² C-H activation. The reported procedure delivers good to high yields of imidazo[1,2-f]phenanthridine derivatives (58-94%) starting from readily available precursors. [ABSTRACT FROM AUTHOR]

A family of heteronuclear metal organic frameworks (MOFs) using lanthanide and transition metal ion based on a rigid ligand of substituted imidazoledicarboxylic acid, namely, {[Ln2Zn2 (|3-Hmimda)2 (μ3-mimda)2-4H2O]n-mn H2O}, Ln = Nd, m = 2 (1), Ln = Ho, m = 3 (2), Ln = Er, m = 2 (3), Ln = Yb, m = 3 (4), [Tb2Co2(μ3-Hmimda)2 (μ3-mimda)2-4H2O]n-2nH2O} (5) and [Dy2Co2 (μ3-Hmimda)2 (μ3-mimda)2-4H2O]n-nH2O} (6), (H3mimda = 1H-2-methyl-4,5-imidazole-dicarboxylic acid), have been developed and characterized. All the complexes (except for a little disparity for 1) are isostructural, and all crystallize in the monoclinic system. They possess an extended reticular-like porous structure constructed from corrugated 2D layers. Direct current (dc) magnetic susceptibility measurements for 1 - 5 indicated depopulation of the Stark components at low temperature and/or possible weak anti-ferromagnetic interactions within heteronuclear MOFs. Alternating current (ac) susceptibility studies reveal that the Dy(iii)--Co(ii) complex exhibits both possible ferromagnetic couplings and frequency-dependent out-of-phase signals, behaviour of single-ion magnet nature. Fluorescence properties of series complexes both in near-infrared (NIR) and visible regions have been comparatively studied. [ABSTRACT FROM AUTHOR]

Presented here are three imidazole-linked tetrahedral zinc phosphonate frameworks based on a special ligand 2-(1-imidazole)-1-hydroxyl-1,1'-ethylidenediphosphonic acid (= ImhedpH4) with both an organic imidazole linker and inorganic phosphonate groups. Three new compounds, namely, [Zn2(ImhedpH2)2(ox)]- (H2ppz) (1), Zn3(ImhedpH)2(H2O)4 (2) and [Zn3(Imhedp)2](H2ppz) (3) (ox = oxalate and ppz = piperazine), were obtained by hydrothermal synthesis and structurally characterized by single-crystal X-ray diffraction. Compound 1 shows a chain structure with the ox ligands linking the [Zn2(ImhedpH2)2] units, and the resulting chains are further connected to form a 3D structure through the strong N-H⋯O and O-H⋯O hydrogen bonds between the neighboring chains. Compound 2 displays an inorganic layer structure with dangling imidazole units, where these protonated imidazoles also act as pillars between adjacent inorganic layers. Compound 3 features an unusual chiral three-dimensional (3D) Zn-Imhedp framework with guest H2ppz2+ cations. It can be topologically represented as a 4-connected qtz network. Furthermore, the luminescent properties of the three compounds were investigated in the solid state. [ABSTRACT FROM AUTHOR]

An efficient eight-step synthesis of the title compound, starting from oxoacetic acid monohydrate, was developed. Conden-sation of oxoacetic acid monohydrate with N,N-dimethylethana-mine followed by reductive amination and protection gave N-(tert-butoxycarbonyl)-N-[2-(dimethylamino)ethyl]glycine. Activation of this intermediate with 1,1'-carbonylbis-1H-imidazole followed by treatment with (methoxyamino)methane gave tert-butyl [2-(dimeth-ylamino)ethyl]{2-[methoxy(methyl)amino]-2-oxoethyl}carbamate, which upon reaction with [4-fluoro-3-(trifluoromethyl)phe-nyl]magnesium bromide, generated in situ, and subsequent deprot-ection gave 2-{[2-(dimethylamino)ethyl]amino}-1-[4-fluoro-3-(trifluoromethyl)phenyl]ethanone dihydrochloride. Coupling of this diamine with an activated carboxylic acid gave tert-butyl 4-{1-[2-(dimethylamino)ethyl]-4-[4-fluoro-3-(trifluoromethyl)phenyl]-1H-imidazol-2-yl}piperidine-1-carboxylate, which on treatment with sodium acetate in ethanol followed by deprotection in situ and neutralization gave the title compound in good yield. [ABSTRACT FROM AUTHOR]

Abstract: In this paper the novel N-cycloalkyl-(cycloalkylaryl)-2-[(3-R-2-oxo-2H-[1,2,4]triazino[2,3-c]quinazoline-6-yl)thio]acetamides synthesis by aminolysis of activated by thionyl chloride or carbonyldiimidazole [(3-R-2-oxo-2H-[1,2,4]triazino[2,3-c]quinazolin-6-yl)-thio]acetic acids and alkylation of the 3-R-6-thio-6,7-dihydro-2H-[1,2,4]triazino[2,3-c]quinazoline-2-ones potassium salts with N-cycloalkyl-(cycloalkylaryl)-2-chloroacetamides are proposed. The structures of compounds are determined by 1H, 13C NMR, LC-MS and EI-MS analysis. The in vitro anticancer, antibacterial activity and Photobacterium leiognathi Sh1 bioluminescence inhibition of synthesized compounds were revealed. SAR results were discussed. Compound 4.10 was found to be the most anticancer active one, selectively influenced on the non-small cell lung and CNS cancer cell lines, especially on the HOP-92 (log GI50 = −6.01) and U251 (log GI50 = −6.00). [Copyright &y& Elsevier]

Novel, one-step synthetic routes for the preparation of 1-methyl-2,4,5-trinitroimidazole (MTNI) are described. In addition, a new, molten-state nitration method for the synthesis of 1-methyl-2,4,5-trinitroimidazole is developed. [ABSTRACT FROM AUTHOR]

Abstract: 1,6-Dibenzylglycoluril is not accessible via classical condensation reaction between substituted urea and glyoxal. In this paper 1,6-dibenzylglycoluril was successfully prepared by alkylation of 1,6-diacetylglycoluril with benzylbromide for the first time. 1,6-Dibenzylglycoluril reacted with formaldehyde to give tetrabenzylglycoluril dimer. Deprotection of this dimer and the previously reported o-xylyleneglycoluril dimer was achieved by dissolving metal reduction, whereas propyleneglycoluril dimer was deprotected by action of potassium persulfate. [Copyright &y& Elsevier]

Abstract: In this paper, three kinds of imidazole derivatives, 2-(4-methylphenyl)-4,5-di(2-furyl) imidazole (MDFI), 2-(4-nitrophenyl)-4,5-di(2-furyl) imidazole (NDFI), and 2-(4-tert-butylphenyl)-4,5-di(2-furyl) imidazole (t-BDFI) were synthesized. In an alkaline medium, the chemiluminescence (CL) reaction of imidazole derivatives with H2O2 has been investigated. It was also found that MDFI/H2O2 and t-BDFI/H2O2 systems gave strong CL. When Co2+ was added into the two CL systems, the CL intensity was remarkably enhanced. In the optimum conditions, the CL intensity is linearly related to the logarithm of concentration of Co2+. The linear ranges are 5×10−9–2.5×10−7 mol/L for MDFI/H2O2 system and 5×10−9–2.5×10−7 mol/L for t-BDFI/H2O2 system, and the corresponding detection limits are 1.2×10−9 mol/L and 1.1×10−9 mol/L, respectively. The method was applied to the determination of Co2+ in vitamin B12 injection. Furthermore, the CL mechanism was also discussed. [Copyright &y& Elsevier]

An expedient approach to the difluoromethylation of imidazoles and benzimidazoles has been developed. The key feature of the procedure is the gradual generation of the difluoromethylation reagent in the reaction mixture, which is achieved by the simultaneous addition of chlorodifluoromethane and alkali. The method is applicable to functionalized substrates and allows the corresponding 1-(difluoromethyl)imidazoles and -benzimidazoles to be prepared in 60-95% yield on a hundred-gram scale. [ABSTRACT FROM AUTHOR]

This work outlines the synthesis and solid-state structures of a series of ureidoimidazole derivatives. The ureidoimidazoles all adopt a common tautomeric configuration and possess remarkably consistent features of supramolecular organisation that are affected by both steric factors and proximal hydrogen-bonding functionality. [ABSTRACT FROM AUTHOR]

Abstract: Three new peptidehydroxamic acids (l-alanyl-l-histidinehydroxamic acid, l-Ala-l-HisNHOH, l-alanyl-l-alanyl-l-histidinehydroxamic acid, l-Ala-l-Ala-l-HisNHOH and l-histidyl-l-alaninehydroxamic acid, l-His-l-AlaNHOH) were synthesized and their complexation with Cu(II), Ni(II) and Zn(II) were studied by pH-potentiometric, UV–Vis, CD, 1H NMR, EPR and ESI-MS methods. Each of the studied peptide derivatives involves one side-chain imidazole unit and the effect of this group on the metal binding of the hydroxamic moiety is evaluated in the paper. The obtained results are compared to those of the complexes of some histidine-containing di- or tripeptides and also to those of hydroxamic derivatives of aliphatic peptides. A competition between the hydroxamate and imidazole functions occurs in all systems, but the extent differs from metal to metal, from ligand to ligand and depends very much on the pH. The imidazole was found to play the most determinant role in the Cu(II) complexes, somewhat less in the Ni(II)-containing ones, while (except the case of l-Ala-l-HisNHOH) negligible role was found in the Zn(II)-complexes. Common feature of the Ni(II)- and especially Cu(II)-containing systems is that if an imidazole-N is displaced by a hydroxamate, imidazole-bridged di- and polynuclear complexes are formed. [Copyright &y& Elsevier]

Biologically active novel piperidin-4-one oxime carbamates were synthesized from 3-ethyl-1-methyl-2,6-diphenylpiperidin-4-one oxime, 1,1′-carbonyldiimidazole ( CDI), and primary or secondary amines in the presence of sodium hydride as base. Commercially available, cheaper, and safer CDI was utilized as carbonyl source, instead of toxic phosgene/triphosgene and carbon monoxide. The devised method is feasible for primary and secondary amines to make their corresponding oxime carbamate derivatives, through oxime-imidazolide intermediate, in high yield. When the antimicrobial activity of obtained oxime carbamate derivatives was investigated in comparison with streptomycin and amphotericin B as standards, the oxime carbamate containing heteroaromatic thiazole ring exhibits outstanding antimicrobial effectiveness, regardless of bacterial or fungal types. [ABSTRACT FROM AUTHOR]

The commercially available 7-methoxy-α-tetralone was subjected to bromination, reduction and protection respectively to obtain the tert-butyldimethylsilyl derivative compound whose conversion into the title compound tetralone was accomplished in three steps (methylation, deprotection and oxidation). [ABSTRACT FROM AUTHOR]

An efficient P(V)–N activation approach for the synthesis of cytidine diphosphate choline (CDP-choline) and related ribo- and deoxyribonucleotide analogs has been established. [ABSTRACT FROM PUBLISHER]

5-Aryl-2-[(5-substituted-3-methoxy-2-hydroxybenzylidene)-hydrazine]-thiazoles ( 3a,b) and 3-[(5-substituted-3-methoxy-2-hydroxybenzylidene)amino]-4-oxo-imidazolidin-2-thiones ( 4a,b) were prepared via cyclization of 5-substituted-3-methoxy-2-hydroxy-benzaldehyde thiosemicarbazones ( 2a,b) with ώ-bromomethyl aryl ketones and ethyl chloroacetate in fused sodium acetate. Acetylation of thiazoles and imidazolidinone derivatives with acetic anhydride yielded the diacetyl derivatives ( 5a,b and 6a,b). Acetylation of 4 with acetic anhydride in fused sodium acetate gave the corresponding triacetyl derivatives ( 7a,b). Synthesized compounds were characterized by EI-MS and NMR spectroscopy. The biological activity studies of thiazoles and imidazolidinone were carried out against antimicrobial and anticancer activities. [ABSTRACT FROM AUTHOR]

The article describes ionic liquids [bmim][NO3] in the presence of 30% mol CuI as efficient media for the domino Knoevenagel–hetero–Diels–Alder reaction ofo-propargyloxy benzaldehydes as unactivated terminal alkynes with some active methylene compounds. Short reaction time, easy workup, good to excellent yields, and mild conditions are advantages of this new media. Supplemental materials are available for this article. Go to the publisher's online edition ofSynthetic Communications®to view the free supplemental file. [ABSTRACT FROM AUTHOR]

A facile method of synthesis of 4H-pyrazino[1,2-a]- pyrimidine-4,9(8H)-diones and imidazo[1,2-a]pyrazin-8(7H)-ones from the corresponding 3-amino-2(1H)-pyrazinones is described. [ABSTRACT FROM AUTHOR]

The nucleophilic substitution reaction of carbohydrate imidazole-1-sulfonates with pyrrole and other nitrogen heterocyclic compounds is reported for the first time. Several novel N-carbohydrate-derived heterocyclic compounds have been prepared by this displacement reaction. The desired carbon-nitrogen bond formation proceeds under mild conditions to generate the coupling products in good yields with readily available and inexpensive reagents. This method is particularly suitable for carbohydrate imidazole-1-sulfonates of primary alcohols. Supplemental materials are available for this article. Go to the publisher's online edition of Journal of Carbohydrate Chemistry to view the free supplemental file. [ABSTRACT FROM PUBLISHER]

A series of novel hybrid heterocyclic compounds, 3-(3-alkyl-2,6-diarylpiperin-4-ylidene)-2-thioxoimidazolidin-4-ones were synthesised and a comparative study was also carried out under microwave irradiation. The synthesised compounds were characterised by their melting points, elemental analysis, MS, FT-IR, one-dimensional NMR (1H, D2O exchanged 1H and 13C), two dimensional HOMOCOSY and NOESY spectroscopic data. All the synthesised title compounds were screened for their in vitro antibacterial and antifungal activity against clinically isolated strains namely B. subtilis, M. luteus, S. typhii, S. paratyphii B, S. felxneri, P. vulgaris, A. niger, Mucor, Rhizopus and M. gypsuem and the results were discussed. [ABSTRACT FROM AUTHOR]

Taking into account the structure-activity relationship established previously for imidazobenzimidazole derivatives with high hemorheological activity, several new 9- R-2-halogenophenyl-substituted imidazo[1,2- a]benzimidazoles with C fluoro-, chloro-, dichloro-, or bromo-phenyl radicals have been synthesized. All substances were tested in vitro for various types of pharmacological activity characteristic of this class of drugs including hemorheological, antiplatelet, antiarrhythmic, antioxidant; 5-HT-, 5-HT-, P2Y-, and H-antagonist; and κ-opioid-agonist. [ABSTRACT FROM AUTHOR]

2-Phenyl-5-(2-furyl)- and 2-phenyl-5-(2-thienyl)imidazoles were synthesized by condensation of 2-furoylmethyl and 2-thenoylmethyl acetates with benzaldehyde under the conditions of Weidenhagen reaction. The products were converted to N-methyl derivatives in the KOH-acetone system. The electrophilic substitution reactions of the products (acylation, bromination, nitration, sulfonation, hydroxymethylation) were studied. [ABSTRACT FROM AUTHOR]

Hydantoins have been known as medicinally active compounds since the 1940s and thiohydantoin derivatives are currently undergoing clinical trials as potent androgen receptor antagonist drugs. Control of solid state properties including the formation of drug polymorphs is important to the pharmaceutical industry, and frequently results from different H-bonded motifs. N–H thiohydantoins show formation of H-bonded arrays in the solid state. Two novel and five known thiohydantoin derivatives were synthesised viareaction of alkyl isothiocyanates with amino acid methyl esters. X-Ray crystallographic data were obtained for all seven compounds showing that four of the structures contain hydrogen bonded dimeric units linked viaN–HS interactions and three of the structures have N–HO linked H-bonded chains. [ABSTRACT FROM AUTHOR]

A series of 2,4,5-triarylimidazoles was synthesized from a new, highly efficient and green method. The reaction is performed in water, without the presence of any catalyst, and under microwave irradiation. This provides new opportunities for the rapid screening of a wide range of compounds, either for the development of new drugs, or original compounds for the material scientist. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) are being considered as a promising class of potentially environmentally-friendly (“green”) solvents and materials for use in a variety of applications. However, ionic liquids are conventionally synthesized by batch, without known kinetics, in non-sustainable solvents. For ILs to be a truly “green” technology for widespread use, they must themselves be made in a correspondingly benign manner for low cost, as enabled by process development. This investigation will illustrate the kinetics and large solvent effects in the synthesis of 1-hexyl-3-methyl-imidazolium bromide in 10 different solvents: acetone, acetonitrile, 2-butanone, chlorobenzene, dichloromethane, dimethyl sulfoxide (DMSO), ethyl formate, ethyl lactate, methanol, and cyclopentanone. The kinetic rate constant for the synthesis in DMSO is over an order-of-magnitude larger than that in methanol. While the kinetic rate of these type of SN2 reactions is generally known to increase with solvent “polarity”, multi-parameter solvent descriptors, e.g.of Kamlet and Taft, are required to quantify these effects in a Linear Solvation Energy Relationship. These relationships are used with environmental and toxicity databases, such as the Rowan Solvent Selection Table, to rapidly optimize the solvent for favorable kinetics and minimal human and environmental impact. [ABSTRACT FROM AUTHOR]

A simple, efficient, and practical procedure for synthesis of 2,4,5-trisubstituted-1H-imidazoles via the condensation of benzoin or acetoin, aromatic aldehydes, and ammonium acetate using europium triflate [Eu(OTf)3] as a novel catalyst in high yields is described. The catalyst can be recovered conveniently and reused at least four times without any loss of activity. [ABSTRACT FROM AUTHOR]

The mononuclear complex, Ni[N³-ImSP(OiPr)2]2[S2P(OiPr)2]2 (Im = imidazole; iPr=isopropyl), was unexpectedly obtained in a reaction of bis(O,O'-diisopropyldithiophosphato) nickel(II) complex with imidazole ligand, and its structure was determined by X-ray crystallography. It crystallizes in the triclinic system, space group P&1macr;, with lattice parameters a=12.437(3) Å, b=13.181(3) Å, c=8.4580(17) Å, α = 93.16(3)°, β = 101.93(3)°, β = 65.26(3)°, and Z = 1. The Ni atom has almost perfect octahedral coordination geometry and is coordinated by two N atoms of imidazole from two O,O'-diisopropylthiophosphoryl-1H-imidazole ligands in axial positions and four S atoms from two (O,O'-diisopropyldithiophosphato) anions which act as bidentate ligands forming a four-membered chelate ring in the equatorial plane. The Ni-S bond distances are 2.469(1) and 2.507(1) Å, and the Ni-N bond distances are 2.097(2) Å. The IR spectra data are in agreement with the structural data. [ABSTRACT FROM AUTHOR]

Abstract: In this work, the 1-allyl-3-alkylimidazolium chloride ionic liquids were synthesized and characterized by increasing carbon atoms (n ≤6) of alkyl chains on a cationic 3-imidazole ring. The results indicated that 1-allyl-3-alkylimidazolium chloride with asymmetrical structure on the two sides of a cationic 3-imidazole ring (i.e., n =1, 2, 6) exhibited alkalinity and lower thermal stabilities, and showed better solubility to the cellulose samples at 60–120°C than those with symmetrical structures (n =3, 4). The cellulose samples treated by 20% (w/w) ethylenediamine solution showed better solubility in 1-allyl-3-ethyl, hexyl-imidazolium chloride ionic liquids than that treated with 20% (w/w) NaOH solution at 5°C for 72h. XRD and TG analysis indicated that 002 plane apparent crystallite size as well as thermal stability of the regenerated cellulose samples from the ionic liquids decreased significantly compared with the untreated cellulose samples. [Copyright &y& Elsevier]