10). In the 1H NMR spectra corresponding to the mixtures of rosin acids used as template (Fig. 10), characteristic zones can be distinguished. The signals between 0.5–0.8 and 1.0–1.2 are attributed to the singlets and doublet of doublets generated

by the presence of methyl groups [27] and [28]. The region between 1.3 and 2.0 ppm is a group of high multiplicity signals, associated with methylen groups. In the range 5.0–6.0 ppm it can be observed signals associated with the olefinic zone, endo and exocyclic bonds Ceritinib solubility dmso [27], which indicated the presence of the abietic acid. In addition, at 6.8–7.3 ppm there are four characteristic signals (3 aromatic protons) which may be associated to the dehydroabietic acid. The calculated spectra using ACD Labs package was in agreement with the experimental data (Fig. 10). To model the extract, it was proposed

a theoretical mixture of resinic acids commonly found in the Pinus caribaea rosin. A comparison between the 1H NMR experimental and calculated spectra revealed similar signal patterns. The study of both spectra allowed us to infer that the structure-directing agent consists of a mixture of resinic acids among which there are the abietic, dehydroabietic and levopimaric acids as major compounds. 13C High Content Screening NMR spectrum (between 120 and 135 ppm) revealed the existence of a characteristic pattern of cyclic olefin, and aromatic systems. Moreover, at 179.6 ppm it was observed a signal confirming the existence of carboxylic functional group. Finally the typical area for signals corresponding to atoms of saturated carbon chains and cyclic subsystems (CH); (CH2) is observed between 17 and 28 ppm [27]. The calculated 13C NMR spectrum was consistent with that observed in 1H NMR studies between 120 and 135 ppm.

We have shown that colophony extract obtained from Pinus caribaea can be used as a mixture of organic Flucloronide acids for preparation of carboxylate substituted Al2O3 nanoparticles. TEM micrographs show nanoparticles with range in size from 5 to 8 nm. The obtained materials displayed high surface areas (183 m2/g) and narrow pore size distribution centred at 10 nm. FTIR analysis showed that carboxylate ligands are still bound to the aluminum oxide surface, even after calcination at 650 °C. The XRD patterns and 27Al MAS NMR spectrum confirm the obtaining of γ-Al2O3 phase. Financial support for this work was provided by the Instituto Venezolano de Investigaciones Científicas through Project 1077. To Lic. Liz Cubillán for assisting with the FTIR analyses. I am grateful to the editor and anonymous referees for helpful suggestions to improve this manuscript. “
“Second-generation biofuel production from renewable biomasses is being explored as an energy alternative because of the rising fuel costs, exhaustion of crude oil resources, and environmental problems, such as global warming, caused by the use of fossil fuels [9] and [16].