An ionic liquid (IL) 111 column was compared with other commonly employed stationary phases including polydimethyl siloxane and polyethylene glycol for the separation of fatty acid monomethyl and dimethyl esters. The fatty acid esters employed in this study were derived from metathesis reactions of vegetable oils both with and without olefins. The IL 111 column demonstrated enhanced performance compared with conventional columns for the separation of these esters. These advantages included significantly enhanced retention of dimethyl esters relative to monomethyl esters, excellent cis/trans isomer separation and the ability to analyze higher carbon number dimethyl esters. As a result, these columns are highly suited for the analysis of mixtures of mono- and dimethyl fatty acid esters found in lipid metathesis reaction products or to determine monofunctional impurities in samples of commercial dimethyl esters.

We describe the design, synthesis, and antitumor activity of an 18 carbon α,ω-dicarboxylic acid monoconjugated via an ester linkage to paclitaxel (PTX). This 1,18-octadecanedioic acid-PTX (ODDA-PTX) prodrug readily forms a noncovalent complex with human serum albumin (HSA). Preservation of the terminal carboxylic acid moiety on ODDA-PTX enables binding to HSA in the same manner as native long-chain fatty acids (LCFAs), within hydrophobic pockets, maintaining favorable electrostatic contacts between the ω-carboxylate of ODDA-PTX and positively charged amino acid residues of the protein. This carrier strategy for small molecule drugs is based on naturally evolved interactions between LCFAs and HSA, demonstrated here for PTX. ODDA-PTX shows differentiated pharmacokinetics, higher maximum tolerated doses and increased efficacy in vivo in multiple subcutaneous murine xenograft models of human cancer, as compared to two FDA-approved clinical formulations, Cremophor EL-formulated paclitaxel (crPTX) and Abraxane (nanoparticle albumin-bound (nab)-paclitaxel).

AbstractOlefin metathesis provides an attractive and versatile route for the catalytic transformation of triglyceride‐based fats and oils into renewable chemical intermediates. Cross‐metathesis reaction of triglycerides with α‐olefins followed by transesterification leads to a complex array of olefins, fatty acid methyl esters, and fatty acid dimethyl esters. In order to evaluate the commercial value of these mixtures and to optimize process conditions, it is necessary to obtain detailed, quantitative, compositional information. With standard, one‐dimensional, gas chromatographic approaches, complete resolution of all components of interest with short analysis times is difficult to achieve. In this report we describe a rapid, microfluidic, two‐dimensional gas chromatographic methodology suitable for the detailed componential analysis of these complex mixtures. The precision of this method for individual components, as measured by the relative standard deviation, is on the order of 1 % or less, and the recovery of known blends of esters and olefins averaged 100 %.

Synthetic pathways to (NH4)2RuCl6 and [RuCl2(COD)]x from mixed ammonium ruthenium (oxide) chlorides (ARC) have been developed that bypass the current, energy intensive route through Ru metal and RuCl3·nH2O. Hydrothermal treatment of ARC with concentrated HX (X=Cl, Br) produces (NH4)2RuX6 in up to 94% yield. Further reaction of (NH4)2RuCl6 with 1,5-cyclooctadiene in ethanol with 1 equivalent FeCl2 affords [RuCl2(COD)]x in up to 89% yield for an overall yield of 84%.

Three pure jojoba wax-like esters (JLEs), i.e., octadec-9-enyl dec-9-enoate (JLE 281), dec-9-enyl oleate (JLE 282), and dec-9-enyl dec-9-enoate (JLE-20), were synthesized from fatty acids and fatty alcohols. Calorimetric, solid fat content evolution, and flow data were used to elucidate the phase behavior of the JLEs. It was clearly established that the length of the terminal alkyl chain and orientation of the linking group in the side chains of the bent-core molecules play an important role in the phase development of the JLEs and ultimately their physical properties. Measurable differences in all physical properties investigated were detected between the isomers based on the position of the ester group in the molecule, leading to informed choices on what isomer should be synthesized for similar monoesters for specific applications.

A comprehensive study of branched derivatives of four pure jojoba wax-like esters (JLEs), having 36, 40 (two isomers), and 44 carbons was conducted to elucidate their crystallization and melting behavior. Crystallization and melting characteristics depended strongly on the number of branches, molar mass, and symmetry. The derivatives demonstrated a very strong tendency to form glassy liquids rather than crystal phases and remain liquid-like at very low temperatures. As the number of branches increased, their crystallinity decreased drastically while their glassy phase increased concomitantly with the depression of the onset of crystallization and/or glass transition temperature. A variety of possible transformation paths, ranging from very little polymorphic activity to extremely polymorphic behavior, depending on number of branches, mass, and symmetry were revealed. It is shown that asymmetry plays a large role in the low temperature behavior, rendering the branched derivatives of the asymmetrical JLEs much better candidates for lubricant formulations.

The catalytic activity of a highly reactive and attrition resistant regenerable CuO/γ-Al2O3 desulfurization sorbent for NOx reduction was determined in a fluidized-bed reactor. The NO conversion over the sulfated catalyst was found to be higher than that obtained over the fresh/oxidized catalyst, with the optimum temperatures for the maximum NO removal at 350°C for both catalysts. The decrease in NO conversion above the optimum temperature is attributed to the increase in the rate of the parallel NH3 oxidation reaction. High levels of ammonia oxidation (i.e., >96%) was observed in absence of oxygen and NO with oxidized sorbent/catalyst, indicating the participation of the lattice oxygen ions in the CuO/γ-Al2O3 particles in the NH3 oxidation reaction. The presence of steam enhances the catalytic activity of the catalysts providing a wider optimum temperature window, thus resulting in a more flexible operation for simultaneous SOx/NOx removal from flue gas.

The modified expanding grain model, presented in the part-2 of this series of papers, is extended to describe the sorbent behavior in a long-term cyclic process using the experimental data obtained in a 25-cycle sulfation/regeneration test. The model extension uses one adjustable parameter to describe the changes in the diffusional resistances occurring within the sorbent particle to predict the behavior of the sorbent undergoing an extended cyclic process. The model suggests that during the cyclic process, because of the cracks and fissures developing within the product layer of the grain, the product layer porosity and the product layer diffusivity of the grain as well as the tortuosity parameter gradually increase, resulting in lower intergrain diffusivity and lower overall sorbent reactivity. The model was used to predict the long-term performance of the sorbent to estimate the fresh sorbent makeup rate in the regenerative copper-oxide process. The results indicate that the sorbent makeup rate generally correspond to a useful sorbent life of higher than two years, but is highly sensitive to the slope of the extrapolation line for the sorbent deactivation.