SiO2-SO3H, with a surface area of 115 m2/g, pore volumes of 0.38 cm3g−1 and 1.32 mmol H+/g, was used as a 10% w/w catalyst for the preparation of 5-hydroxymethyl-2-furfural (HMF) from fructose. A conversion of 100% was achieved in a microwave reactor during 10 min at 150 °C in DMSO, with 100% selectivity for HMF, at a molar ratio of fructose: DMSO equal to 1:56. The catalyst could be re-used three times.

No abstract

No abstract

No abstract

No abstract

SiO2–SO3H, with a surface area of 115 m2/g and pore volume of 0.38 cm3g−1, and 1.32 mmol H+/g was used as a 20% w/w catalyst for the preparation of methyl salicylate (wintergreen oil or MS) from acetylsalicylic acid (ASA). A 94% conversion was achieved in a microwave reactor over 40 min at 120 °C in MeOH. The resulting crude product was purified by flash chromatography. The catalyst could be reused three times.

SiO2-SO3H, with a surface area of 115 m2·g−1, pore volumes of 0.38 cm3·g−1 and 1.32 mmol H+/g, was used as a transesterification catalyst. Triglycerides of waste cooking oil reacted with methanol in refluxing toluene to yield mixtures of diglycerides, monoglycerides and fatty acid methyl esters (FAMEs) in the presence of 20% (w/w) catalyst/oil using the hydrophilic sulfonated silica (SiO2-SO3H) catalyst alone or with the addition of 10% (w/w) co-catalyst/oil [(Bun4N)(BF4) or Aliquat 336]. The addition of the ammonium salts to the catalyst lead to a decrease in the amounts of diglycerides in the products, but the concentrations of monoglycerides increased. Mixtures of (Bun4N)(BF4)/catalyst were superior to catalyst alone or Aliquat 336/catalyst for promoting the production of mixtures with high concentrations of FAMEs. The same experiments were repeated using DMSO as the solvent. The use of the more polar solvent resulted in excellent conversion of the triglycerides to FAME esters with all three-catalyst media. A simplified mechanism is presented to account for the experimental results.

Pain is the most common complaint in the medical field and the identification of compounds that can effectively treat painful states without induction of side-effects remains a major challenge in biomedical research. The aim of the present study was to investigate the antinociceptive effect of a novel compound, 3-(4-fluorophenyl)-5-trifluoromethyl-1 H -1-tosylpyrazole (compound A) in several models of pain in mice and compare with those produced by the known trifluoromethyl-containing pyrazole compound celecoxib. Compound A or celecoxib were administrated by oral (78-780 μ mol/kg), intrathecal (9-22.5 nmol/site) or intracerebroventricular (9-22.5 nmol/site) routes. Oral administration of either compound A or celecoxib abolished the mechanical allodynia, but not the oedema caused by intraplantar injection of carrageenan. Similarly, compound A reduced the overt nociception, but not the oedema, produced by bradykinin or capsaicin. However, compound A (500 μ mol/kg, orally) did not alter nociception nor oedema caused by intraplantar injection of prostaglandin E 2 or glutamate, whereas celecoxib reduced only the nociception induced by the former. Moreover, oral and intrathecal administration of compound A or celecoxib also reduced the nociception induced by acetic acid. However, only celecoxib reduced the acetic acid-induced nociception when it was injected by the intracerebroventricular route. Finally, neither compound A nor celecoxib was able to produce antinociceptive effect in the tail-flick test or to alter the motor performance and the body temperature. Besides, compound A or celecoxib did not induce gastric lesion. Thus, compound A seems to be an interesting prototype for the development of novel analgesic drugs.