of the solvent, the residue was purified and affording diethyl 2,3-bis(2-methoxybenzoyl)succinate. Toluene-p-sulfonic acid (5 g) was added to a solution of compound diethyl 2,3-bis(2-methoxybenzoyl)succinate (2.2 g, 5 mmol) in dry benzene (50 ml). The mixture was refluxed for 8 h and concentrated. The residue was chromatographed on silica gel (light petroleum–ethyl acetate, 8:1 (v/v) to give diethyl 2,5-bis(2-methoxyphenyl)furan-3,4-dicarboxylate which was hydrogenated, oxidized and decarboxylated to give the title compound. Crystals suitable for X-ray analysis were obtained by recrystallization of the the title compound from ethanol over a period of two weeks.
The Aldrich and the Merck Chemical Co. were the suppliers for the nitrate and chloride salts of all cations, the reagent grades of benzylacetate (BA), dibutyl phthalate (DBP), acetophenone (AP), sodium tetraphenyl borate (NaTPB), tetrahydrofuran (THF) and relatively high molecular weight PVC. The ionophore 1,4-bis[o-(furan-2-carboxamidophenyl)]-1,4-dithiobutane was prepared as formerly described [26-29]. All reagents were used without any modification. As far as the nitrate and chloride salts of all employed cations are concerned, they were of the highest available purity and were P 2 O 5- vacuum dried. During the experiments, triply distilled deionized
In conclusion, 2,5-bis(aminomethyl)furan was prepared by the direct reductive amination of 2,5-diformylfuran with ammonia in one step approach. The Ni-Raney catalysts showed reductive amination activities in THF- water mixed medium. The BAF yield of 42.6% was achieved when the acid treated Ni-Raney catalyst was ap- plied under the optimal reaction conditions. It is proposed that the combination of THF-water mixed medium and the Ni 0 component of the Ni-Raney catalysts plays a crucial role in the DFF reductive amination to BAF. Moreover, XPS, BET surface area and EDXRF analysis also support that the BAF formation is related with the Ni 0 component of the Ni-Raney catalysts. The oligomeric imine trimer and tetramer species, confirmed by MALDI-MS analysis, are suggested as main intermediates in the direct reductive amination of DFF to BAF.
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Having previously identified the target of our original triazole inhibitor series as mitochondrial F1 and established their hypo- thetical binding mode, furan analogues were proposed to pro- vide an alternative framework for future analogue derivatisa- tion. We therefore employed a structure-based approach to de- sign, synthesise and biologically evaluate compounds targeting the FoF1-ATP synthase. Computational docking indicated that binding of furan analogues was feasible, so the compounds were synthesised by the coupling of pairs of THP building blocks to access 1,4-alkyne diols, followed by ruthenium/ xantphos-catalysed heterocyclisation. This successful synthetic route is itself an achievement given the complexity of the alk- yne diol precursors, which to the best of our knowledge, are the most complex substrates thus described for this method of heterocyclisation. Cytotoxicity assays confirmed that many of the synthesised furans were broadly cytotoxic against a panel of kinetoplastid pathogens as well as human HeLa cells, while an F1 ATP synthase assay confirmed that they acted on target at F1. Docking indicated that substitution of the THP-Et (5) for THP-OBn (6–9) could potentially enhance inhibitor binding through favourable π-stacking interactions with the receptor, and while all retained F1-inhibitory properties, enhanced cyto- toxicity was not evident. Inhibitors with terminal hydroxylation appeared to form critical hydrogen bonding interactions. Upon substitution with a benzyl ether moiety a loss of activity against most cell lines was observed along with the loss of F1 inhibi- tion, further indicating the on-target effects of previous ana- logues. Unexpectedly, these di-benzoylated compounds 10, 11 and 12 retained modest activity against T. brucei, with selectivi- ties ranging from 17–34 fold, and therefore represent new lead compounds for further development in finding new treatments for HAT.
The 1,1-dibenzyl-3-[(furan-2-yl)-carbonyl]thiourea ligand was prepared using the standard procedure previously reported in the literature (Nagasawa & Mitsunobu, 1981) by the reaction of furoyl chloride with KSCN in anhydrous acetone, and then condensation with dibenzylamine. To an ethanol solution (30 ml) containing the ligand (0.70 g, 2 mmol) was added an ethanol solution of Cu(CH 3 COO) 2 .H 2 O (0.20 g, 1 mmol). The solution was stirred at room temperature for 2 h, and at
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adopts a twin-chair conformation. The two methyl groups attached to the bicycle are in an equatorial orientation for both rings. One of the furan rings is disordered over two orientations with an occupancy ratio of 0.686 (6):0.314 (6). In the crystal, very long N—H O hydrogen bonds connect the molecules into a chain perpendicular to the ac plane.
as a centrocymmetric furan-2-selenolate-bridged dinuclear palladium complex. The Pd atom shows a slightly distorted square-planar coordination geometry, with bridging Pd—Se distances of 2.4568 (8) and 2.4729 (8) A ˚ , and a terminal Pd— Se distance of 2.4623 (8) A ˚ . Terminal selenolate ligands are in trans positions with respect to each other.
Compound (I) was prepared during an ongoing study into the Lewis-acid-mediated additions of silylated methylenecyclo- propanes to aldehydes. The structure of (I) is composed of a pair of tetrahydrofuran rings fused at the 2- and 3-positions, both substituted at the 5-position by p-nitrophenyl groups. These substituted positions both exhibit R chirality. The axial 3-position of the fused ring system is substituted by a triiso- propylsilyl group (TIPS). Puckering analysis (Cremer & Pople, 1975) shows that the furan ring containing O1 forms an envelope conformation about C3, whilst the ring containing O2 adopts a twisted conformation. The fused rings form a dihedral angle of 68.91 (6) with respect to each other. The
Figures 3 and 4 show cyclic voltammograms for furan and thiophene bis-chalcones where 1.0 mM of each dye were prepared in acetonitrile .The HOMO energy levels of furan and thiophene bis- chalcones were calculated front the onset oxidation potential of cyclic voltammogram. The HOMO energy level of furan bis-chalcone is determined to be 0.811 V versus saturated calomel electrode (SCE) (-5.66 eV versus vacuum), and that of thiophene bis-chalcone lies at 0.792 V versus SCE (-5.59 eV versus vacuum). Based on the offset absorption spectra and HOMO energy, lowest unoccupied molecular orbital (LUMO) energy levels are determined to be -2.843 eV and -2.760 eV for furan and thiophene bis-chalcones, respectively. Energetic data for furan and thiophene bis-chalcones are listed in Table 3. From cyclic voltammogram, It Seems the electrochemical behavior of Chalcone derivatives fallow EC mechanism.
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A convenient method of preparing 2-acetylbenzofuran, (I), from 2-hydroxybenzaldehyde and chloroacetone in the presence of KOH has been reported (Elliott, 1951). We have obtained (I) using a phase-transfer catalytic method. The present X-ray diffraction study was undertaken to understand the geometry of the benzofuran ring system and the effect of acetyl group substitution at position 2 of the furan ring.
neighbouring hydrogen on azatidine ring Further IR spectroscopy proves the presence of –C=O due to the formation of peak at 1673.44 cm-1, 2367.39cm-1and 1785.22 respectively . The molecular mass value indicates the formation of azetidine-2-one and based on the structural conformation the compounds were named as 1-(4-chlorophenyl)-4-(furan-2-yl)-azetidine-2-one, 1-(4-nitrophenyl)-4-(furan-2-yl)-azetidine-2-one, 1-(4-bromophenyl)-4-(furan-2-yl)-azetidine-2- one respectively.
]. The labelling convention for the atoms in the furan ring, used for defining the bondlengths and bond angles in this table, is shown in Fig. 1, and follows the labelling used in the experimental structure determination for the molecule adsorbed on Pd(111) [ ]. All bondlengths from our calculations agree with one or both of the experimental values within better than 0.02 Å, while the largest discrepancy in bond angles is 0.8°. The scatter of these values in the three calculations is never larger, and in most cases smaller, than these differences. Moreover, the results of our PW91 (not shown) and RPBE calculations agree in the molecular geometrical parameters to within 0.002Å and 0.1°.
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bonding of all aggregate particles will be less or use loosely packed aggregate with higher binder content . Though the aggregate and micro filler form a major component of total mass of the polymer concrete, there has not been much emphasis on the aggregate and micro filler mix proportion used in such system. The aggregates used in polymer concrete are either fine particles or the particle size distribution chosen are based on theoretical basis suitable for Portland cement concretes. Also the effect of aggregate mix proportion on void content and method of optimizing mix proportion to have minimum void content has been reported [2,3]. Furan resin offer several advantages over other synthetic resin based binder system such as unsaturated polyester, epoxy etc. The major raw material used in the synthesis of furan polymer is furfuryl alcohol and furfuraldehyde which are obtained from agricultural wastes. Condensation product of furfuraldehyde and acetone in different mole ratio are more commonly used, even though other types of furan resin such as homopolymer of furfuryl alcohol or a copolymer of furfuryl alcohol and furfuraldehyde are also known to be good binder for chemical resistance application. Furan resins can be cured through heat or by addition of a chemical agent [4,5].
In medicinal chemistry nitrogen containing heterocycles are the most important compounds which show various biological activities. The cinnoline are nitrogenous derivatives and found to elicit many pharmacological actions like anti-hypertensive, antithrombotic, antihistamine, antileukemic, CNS activity, anti tumor, antibacterial and antisecretory activity. We planned to synthesis new series of substituted Cinnoline derivatives, and evaluated for antibacterial, antifungal and anti-inflammatory activity. The Cinnoline moiety substituted with different substituents condensed with Pyrazole, Piperazine, Imidazole, Furan and Thiophene moieties separately. The antibacterial and antifungal activities of synthesized compounds were determined by disc diffusion method. The anti-inflammatory activity of synthesized compounds was assessed by rat paw edema method. The synthesized compound exhibited moderate to good antibacterial, antifungal and anti-inflammatory activity. The substituted Cinnoline Piperazine series and Cinnoline thiophene series compound exhibited maximum antibacterial activity and antifungal activity, respectively. The substituted Cinnoline Imidazole series revealed potent anti-inflammatory activity. Further investigations are required to find out possible mechanism of action.
A cooled nitrating mixture of concentrated nitric. acid and concentrated sulphuric acid in the ratio 1:2(6.5ml: 13ml) was added very slowly to a cooled solution of 2-acetylnaphtho [2,1-b] furan (2.1g.0.01mol) in glacial acetic acid(4ml) and the mixture was stirred for about 30 min at 0-5c.The stirring was continued for 3hrs at the same temperature and the reaction mixture was poured on to crushed ice. The product which was separated as solid was collected and dried. Recrystallised from aqueous ethanol. The structure of the compound was established by recording its IR, 1 H NMR and 13 C NMR and comparing it with an authentic sample.
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The most recent version of RST (Gray & McNaughton, 2000; McNaughton & Corr, 2004, 2008; Corr & McNaughton, 2012) postulates three major neuropsychological systems (RST-3): the fight-flight-freeze system (FFFS) is activated by all forms of aversive stimuli (including frustrating nonreward); the behavioural approach system (BAS) by all forms of appetitive stimuli (including relief of nonpunishment); and the behavioural inhibition system (BIS) by all forms of goal conflict, with one major class being (equal) co-activation of FFFS and BAS. As is well known, this is a revision of the original RST formulated by Gray (1982) that laid emphasis upon only two of these systems, the BIS and the BAS (RST-2). What is less apparent is the hidden complexity in and between these systems which renders any attempt to provide a psychometric description of them far from straightforward – indeed, as shown in this article, prone to confusion.
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brain trauma [19, 20]. Immediate comas are typical of DAI patients after the initial injury. The typical coma duration is lengthy and GCS is typically low [21, 22]. In this study, patients that did not survive had much lower GCSs than those that did survive. However, logistic regres- sion analysis did not indicate GCS as an inde- pendent variable in the assessment and evalu- ation of DAI, likely the result of the subjective nature of GCS. Even for the same patients, GCS can vary among different examiners. It is also subjected to factors such as the adoption of tracheotomies and tracheal intubation, as well as administration of sedative drugs and obser- vation of facial edema, in severe DAI cases. As a result, there remains great uncertainty in using GCS as an indicator of DAI severity and as an input for prognosis. In early stages, serum NSE and S100 can be valuable indicators of trauma severity, providing sound prognoses. However, due to the inherent lag of results and the frequency of blood work needed, real time continuous monitoring is often impractical. BIS is a more intuitive and objective alternative for DAI monitoring, with wider application. For example, in coma patients where verbal cues are not usable, BIS provides direct monitoring of electroencephalogic activity. In addition, BIS is non-intrusive, easy to operate, and allows for continuous monitoring. Present results are con- sistent with previous study results [23, 24]. In conclusion, BIS is an objective index benefi- cial for early stage evaluation and prognosis of DAI. Therefore, it is worthy of extensive clinical application. However, there were some limita- tions to the current study. This study included a small sample size and it was a single-center trial. Moreover, this study did not indicate BIS changes at different time points, subdivisions of BIS within 24 hours, and influence of DAI pro- gression on BIS. Additional studies are neces- Table 4. Logistic regression analysis between DAI
In the present work, the structure of the 2,4,6-trinitrophenyl furan 2-carboxylate (I) has been determined as a part of an in-depth study of picryl substituted-esters carried out in our research group. Descriptions of similar structures have been published recently: 2,4,6-trinitrophenyl 3-chlorobenzoate (Moreno-Fuquen et al., 2013), and 2,4,6-trinitrophenyl benzoate (Moreno-Fuquen et al., 2012). The molecular structure of (I) is shown in Fig. 1. Bond distances and angles agree with the molecular features exhibited by other picryl substituted-esters, as described in detail in previous work (Moreno-Fuquen et al., 2012 and 2013). The picryl ring forms an angle of 75.79 (7)° with the ester fragment. The nitro groups form dihedral angles with the adjacent benzene ring of 3.22 (10), 16.03 (12) and 36.63 (10)° for O1—N1—O2, O3—N2—O4 and O5—N3—O6, respectively. The atoms at the furanyl ring are disordered over two positions with occupancies refined to 0.730 (9) and 0.270 (9) for C8A–C11A/O9A and C8B–C11B/O9B, respectively. Appropriate restraints were required (see experimental section) to give chemically acceptable geometries for these fragments. In the crystal the molecules are linked by weak C—H···O interactions, forming one-dimensional helical chains running along , as shown in Fig. 2 & Table 1. The C5 atom of the benzene ring at (x, y, z) acts as a hydrogen-bond donor to carbonyl atom O8 at (-x+1, +y-1/2, -z+1/2) (see Nardelli, 1995).
Furan and its derivatives are naturally occurring compounds found at very low levels in many foods and drinks; they have been associated with the fla- vour of foods. They are a major class of compounds forming during the Maillard reactions (Maga 1979). The formation of furan under pyrolytic con- ditions has been studied in simple model systems revealing more precursor classes, i.e., (i) ascorbic acid and related compounds; (ii) Maillard type systems containing amino acids and reducing sugars; (iii) lipid oxidation of unsaturated fatty acids or triglycerides; and (iv) carotenoids (Pe- rez & Yaylayan 2004; Becalski & Seaman 2005; Yaylayan 2006). Furthermore, the effect of ionising radiation on the furan formation in real (apple and orange juice) and model systems has been studied (Fan 2005a, b). Due to its high volatility, furan can be analysed using a headspace or SPME coupled with gas chromatography-mass spectrometry. Furan is rapidly and extensively absorbed from the intestine and the lung. It can pass through biological membranes and enter various organs (Burka et al.1991). Experiments have shown that furan is carcinogenic to rats and mice, showing a dose-dependent increase in hepa- tocellular adenomas and carcinomas in both sexes (NTP 1993). Furan has been classified as possibly carcinogenic for humans (IARC 1995). However, preliminary exposure data suggest that the levels of furan found in foods are well below the levels that would cause harmful effects. Until more is known, FDA recommends that consumers eat a balanced diet, choosing a variety of foods that are low in trans-fat and saturated fat, and rich in high-fibre grains, fruits, and vegetables (US FDA
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activities(4) . More natural furan containing molecules continue to be uncovered at a rapid speed(5). Due to their remarkable properties ,many synthetic furans are utilized as pharmaceuticals.(l) In addition to being building blocks found in natural molecules, poly- substituted furans(6) are important precursors for the synthesis of natural and non natural products(7). Lea Grinblat, Claudia M. Sreider, Andrés O.M. Stoppani (8) showed that nitrofuran derivatives bearing unsaturated five- or six-membered nitrogen heterocycles or related substituents were more effective inhibitors of yeast and rat tissue glutathione reductases than those bearing other groups, such as nitrofurtimox, nitrofurazone and 5-nitro-2-furoic acid. The inhibitory action proved independent of electron withdrawal from the reduced enzyme, as a consequence of redoxcycling of the nitro group. Joshi, et al. (9) discovered potent furan piperazine sodium channel blockers for treatment of neuropathic pain . Yiqiu Fu et al (10) designed and synthesized a novel class of furan-based molecules as potential 20S proteasome inhibitors.