Isomerization of verbenol oxide to (1R, 2R, 6S)-3-methyl-6-(prop-1-en-2-yl)cyclohex-3-ene-1,2-diol, which exhibits anti-Parkinson activity, has been investigated with large and medium pore zeolites, namely H-USY and H-ZSM-5 types of catalysts with different SiO2 to Al2O3 ratio in dimethylacetamide as a solvent. The catalysts were characterized with nitrogen adsorption, 27Al MAS NMR, pyridine desorption, XRD, SEM and TEM techniques. The main reaction product was the target diol with the highest selectivity of 52 % achieved with H-ZSM-5-23 (the last number corresponds to SiO2/Al2O3 ratio) at 49 % conversion of verbenol oxide. The catalyst deactivation was, however, extensive with medium pore zeolites, compared to large pore zeolites. The second highest selectivities to diol with H-USY-80 and H-ZSM-5-80 were about 47–50 mol% at 100 and 78 % of conversion, respectively, achieved at 140 °C within 3 and 5 h. The other main products were the corresponding cyclopentylhydroxyketone and oxetane. A reaction mechanism was proposed.

Galactose units of spruce galactoglucomannan (GGM), guar galactomannan (GM), and tamarind (galacto)xyloglucan (XG) were selectively allylated. Firstly aldehyde functionalities were formed at the C-6 position via enzymatic oxidation by galactose oxidase. The formed aldehydes were further derivatized by an indium mediated Barbier-Grignard type reaction, resulting in the formation of homoallylic alcohols. In addition to allylic halides, the same reaction procedure was also applicable for GGM, when using propargyl bromide as halide. All reaction steps were done in water, thus the polysaccharides were modified in a one-pot reaction. The formation of the allylated, or propargylated, product was identified by MALDI-TOF-MS. All polysaccharide products were isolated and further characterized by GC-MS or NMR spectroscopy. By this chemo-enzymatic process, we have demonstrated a novel method for derivatization of GGM and other galactose-containing polysaccharides. The derivatized polysaccharides are potential platforms for further functionalizations. (C) 2012 Elsevier Ltd. All rights reserved.

Catalytic synthesis of a dioxinol compound, (2S,4aR,8R,8aR)-4,4,7-trimethyl-2-phenyl-4a,5,8,8a-tetrahydro-4H-benzo[d][1,3]dioxin-8-ol, exhibiting analgesic activity was demonstrated over Fe-modified beta zeolite. During interactions between cis-verbenol oxide and benzaldehyde, two main reactions occurred. In the first reaction, namely isomerization of verbenol oxide both cyclopentenic hydroxyketone, oxetane as well as a cyclohexyl compound, (1R,2R,6S)-3-methyl-6-(prop-1-en-2-yl)cyclohex-3-ene-1,2-diol were formed. In the second parallel reaction the target compound was generated. The highest yield of the target compound was achieved in the reaction between verbenol oxide and benzaldehyde at their molar ratio of 1:133 with the bifunctional iron modified Fe-H-Beta-150 catalyst at 70°C giving a much higher yield than reported earlier in the literature, being 46mol-% at complete conversion of verbenol oxide.

In this paper, estimation of the chemical composition of used oils collected from several European locations was performed on the basis of a comparative analysis of chemical composition of commercially available fresh and used motor oils. Although the motor oil undergoes a range of chemical and physical transformations during routine engine operations, information about the structure of hydrocarbons in the fresh oil allows for an estimation of the approximate ratio of different types of hydrocarbons in the same oil after its use. As an example, a particular type of fresh oil was used in the engine and then reanalyzed by the same analytical techniques. Gas chromatography-mass spectrometry (GC-MS), Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and elemental analysis (CHNS/O analysis) were used to characterize the chemical composition of the oil samples. A comparison of the obtained results showed correlations between chemical properties of the fresh oil and the collected used oil. Both oil FTIR spectra exhibited the bands that are related to the presence of carbonyl groups and amine-containing compounds, respectively. Opposite from the fresh oil, phenols were not found in the used oil. According to the obtained H-1 NMR spectra, the paraffinic hydrocarbons of the fresh oil are more linear and have longer chains than those in the used oil.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been shown to be selectively pro-apoptotic in cancer cells, with minimal toxicity to normal tissues. Although this feature makes TRAIL a promising anticancer agent, not all cancer cell types are sensitive to TRAIL-induced apoptosis despite abundant expression of TRAIL receptors. Thus, combinatorial treatments to sensitize tumor cells to TRAIL-induced apoptosis have been in the focus of extensive research. Dietary lignans have shown cancer preventive and antitumorigenic activity, but the mechanisms behind these effects are poorly known. Here we observed that of the three tested lignan molecules, matairesinol (MAT) was the most effective as a death receptor-sensitizing agent. MAT sensitized the androgen-dependent LNCaP cells to TRAIL-induced apoptosis both in the presence and absence of androgens. Treatment with MAT markedly decreased Akt activity, which has been implicated as a key signaling mechanism in the TRAIL resistance of LNCaP prostate cancer cells. The involvement of the pathway in the MAT-mediated sensitization was shown in rescue experiments using ectopic expression of constitutively active Akt. Owing to the high activity of phosphatidylinositol 3-kinase/Akt signaling in cancer, targeting this survival pathway with MAT could markedly benefit TRAIL-based tumor therapies, including those aimed at prostate cancer.

The readily available natural lignan hydroxymatairesinol was transformed into sterically hindered and optically pure diphenyl, di-2-naphthyl, and tetramethyl 1,4-diol derivatives via arylation/alkylation of the aryltetralinbutyrolactone lignan (−)-conidendrin. In addition, the diastereoselective formation of stable hemiketals from the highly substituted butyrolactone was studied in detail. The conformations of the molecules prepared were studied computationally at molecular mechanics (MM), Hartree–Fock (HF)/6-31G∗, and (DFT/B3LYP/TZVP) levels including entropy contributions and by NMR-spectroscopy. The conformations adopted showed that these novel chiral 1,4-diols may be suitable as chiral ligands for the development of new chiral transition metal and organo catalysts.

Norway spruce O-acetyl-galactoglucomannans (GGM) are water-soluble hemicelluloses that have potential to be produced in large scale as a side product of the mechanical pulping industry or by hot-water extraction of wood. Chemical modification is often needed to tailor such water-soluble polysaccharides into industrially valuable compounds. In this work, treatment of GGM with butyric and benzoic anhydride in pyridine/dimethylformamide rendered GGM derivatives, which were hydrophobic and partially soluble in organic solvents. The degree of substitution can be adjusted by varying the quantity of the reagent and reaction temperature. The dn/dc value for the benzoyl ester of GGM was determined in 0.05 M LiBr DMSO in order to obtain accurate molar mass analysis with SEC-MALLS-RI. Novel substances with adjusted hydrophobicity can thus be prepared on one step synthesis from natural hemicelluloses, which then showed a slight increase in the molar mass upon esterification.

Natively acetylated galactoglucomannans (GGMs) is the main hemicellulose type in most softwood species and can be utilised as, for example, bioactive polymers, hydrocolloids, papermaking chemicals, or coating polymers. In this study, carboxymethylated GGMs (CM-GGMs) were prepared and characterised by GC-MS, H-1 and C-13 NMR and FTIR spectroscopy, and SEC-MALLS. The thermal stability of the products was investigated by DSC-TGA. The accessibility of different C-positions in mannose and glucose was investigated. The emulsion stability of CM-GGMs in resin dispersion was studied and it was shown that CM-GGMs can stabilise the resin dispersion also in presence of CaCl2. The possibility of using CM-GGMs as emulsifiers in water-in-oil emulsions was assessed. A CM-GGM with a DS value of 0.25 at a concentration higher than 3% performed the best. Finally, the study of sorption of CM-GGM onto cellulose surface exhibited a decrease in binding ability with an increase in the degree of substitution (DS).

AbstractA convenient, reproducible procedure for the synthesis of the title compounds (III), (VII) and (X) is developed.

Switchable ionic liquids (SILs) made from alcohols, either hexanol or butanol, and CO2 together with an amidine (1,8-diazabicyclo-[5.4.0]-undec-7-ene (DBU)) were investigated as dissolution/fractionation solvents for wood material. Both native spruce (Picea abies), and pre-extracted spruce were treated with either butanol SIL (SIL1) or hexanol SIL (SIL2) for 5 days at 55 degrees C under normal pressure. The SILs were formed by bubbling CO2 through an equimolar mixture of either 1-hexanol or 1-butanol and DBU. The viscosity of the mixture increased from 7.1 mPa s to 2980 mPa s for SIL2 and 5.1 to 1600 mPa s for SIL1. Melting points of the SILs 1 and 2 were at 8 and 14 degrees C, respectively. After the treatment time (5 days). the undissolved fraction contained 38 wt.% less hemicelluloses compared to native spruce. There was an increase in the glucose content of the milled spruce treated with both SILs, since the milling step reduced the cellulose crystallinity of the wood and facilitated an easier SIL access into the wood. The solvents were very neutral in terms of lignin removal. Consequently, only about 2% of the lignin was removed from native wood. Moreover, a priori removal of the wood extractives did not influence the lignin removal. (C) 2011 Elsevier Ltd. All rights reserved.

[image omitted] Six triethylammonium tetra-arylborates (TEATABs) were synthesized via a convenient reproducible procedure and characterized by spectroscopic methods (1H, 13C, 11B NMR and electrospray ionization-high-resolution mass spectrometry). The compounds could be stored at ambient temperature and were useful as reactants in the Suzuki reaction in aqueous conditions when using commercially available catalysts.

New types of switchable ionic liquids (SILs), containing 1,8-diazabicyclo-[5.4.0]-undec-7-ene (DBU), glycerol and an acid gas (CO2, SO2), were synthesized and characterized in this study. [DBU][Carbonate] or [sulfonate] were easily synthesized from a non-ionic mixture of molecular organic polyol and amidine base upon bubbling of an acid gas (CO2, SO2). Moreover, they were switched back to the original molecular solvents by flushing out the acid gas (CO2, SO2) by heating and/or bubbling an inert gas such as N-2 through it. The structures of the SILs were confirmed by NMR and FTIR. The change from low polarity (molecular solvent) to high polarity (Switchable Ionic Liquid, SIL) was also indicated by the changes in properties, such as viscosity and miscibility with different organic solvents. The decomposition temperatures of the SILs were determined by means of Thermo Gravimetric Analysis (TGA) and gave values in the range of 50 degrees C and 120 degrees C for DBU-glycerol-CO2 (SIL1) and DBU-glycerol-SO2 (SIL2), respectively. Due to the reasonable decomposition temperatures, these novel SILs can be employed in multiple applications.

The state of art from the dissolution of cellulose, lignin and wood using ionic liquids is presented in this work. The emphasis is put on the relationship between the properties of ionic liquids and the dissolution capacity. The impact of the following solvation parameters, namely Hildebrand solubility parameter and hydrogen bond basicity are related to the dissolution of lignocellulosic material. Good solvents for cellulose are 1-butyl- and 1-allyl-3-methylimidazolium chlorides as well as 1-ethyl-3-methylimidazolium acetate, whereas for lignocellulosic material the best solvents are 1-ethyl-3-methylimidazolium acetate and 1-allyl-3-methylimidazolium chloride. In allyl group the ethylene functionality facilitates B-interactions with the aromatic lignin structure. Furthermore, small polarizable anions are also powerful when aiming at dissolution of cellulose. The properties of regenerated cellulose and reconstituted lignin are also given and compared with those of the native materials. Furthermore, the results from the regeneration and reuse of ionic liquids are presented here.

Acetylated galactoglucomannans (GGMs) are the main hemicellulose type in most softwood species and can be utilized as, for example, bioactive polymers, hydrocolloids, papermaking chemicals, or coating polymers. Acetylation of spruce GGM using acetic anhydride with pyridine as catalyst under different conditions was conducted to obtain different degrees of acetylation on a laboratory scale, whereas, as a classic method, it can be potentially transferred to the industrial scale. The effects of the amount of catalyst and acetic anhydride, reaction time, temperature and pretreatment by acetic acid were investigated. A fully acetylated product was obtained by refluxing GGM for two hours. The structures of the acetylated GGMs were determined by SEC-MALLS/RI, (1)H and (13)C NMR and FTIR spectroscopy. NMR studies also indicated migration of acetyl groups from O-2 or O-3 to O-6 after a heating treatment in a water bath. The thermal stability of the products was investigated by DSC-TGA.

Stereoselective synthesis of (5R,6R)- and (5S,6S)-5-benzylamino-6-(tert-butyldimethylsilanyloxymethyl)-5,6-dihydropyran-2-ones starting from d-glucal and furanaldehyde, respectively, is described. The synthesis relies on a Sharpless asymmetric dihydroxylation, an Achmatowicz reaction, and a stereoselective Pd-catalyzed allylic amination as the key steps.

The C-6 unit of methyl α-d-galactopyranoside was selectively modified by combining enzymatic oxidation with an indium-mediated allylation reaction. The Barbier–Grignard type reaction, where a carbonyl group reacts with an allyl halide, proceeds in aqueous solution, even with water as the only solvent; thus carbohydrates can be modified without the need for drying or protection–deprotection steps. The corresponding homoallyl alcohols are produced in high yields of >90% in the reactions with allyl bromide and cinnamyl chloride. The main products were isolated and characterized by GC–MS and NMR spectroscopy.

We report here the first selective de-O-methylation of a large panel of guaiacyl lignans to the corresponding catechol derivatives by using IBX as primary oxidant under green conditions (dimethyl carbonate-H(2)O solvent) through an in situ reduction procedure. The influence of the catechol moiety on the cytotoxicity and genotoxicity of new lignan derivatives has been investigated. The results obtained indicated that the presence of the catechol moiety sharply enhances the clastogenic potential (e.g. induction of chromosomal aberrations), the cytotoxicity and the modulation of cell cycle progression with respect to the parent compounds. Thus, despite the in vitro antioxidant activity usually described for catechol derivatives, our results show for the first time the generation of a clastogenic potential, highly indicative of a long-term genetic and cancer risk.

This poster reports the structural elucidation of a novel sesquineolignan with a spirodienone structure (Figure), which we have named as pinobatol [1]. Pinobatol has been isolated from the bioactive fraction from pine bark extract. The structure of it was identified by MS and NMR experiments. The assignment of all 1H and 13C NMR signals was achieved by the combination of techniques DQF-COSY, CH2-edited HSQC, HMBC, NOESY and selective 1D-TOCSY.