A lipid extract of Perna canaliculus (New Zealand green-lipped mussel) has reportedly displayed anti-inflammatory effects in animal models and in human controlled studies. However, the anti-inflammatory lipid components have not been investigated in detail due to the instability of the lipid extract, which has made the identification of the distinct active components a formidable task. Considering the instability of the active component, we carefully fractionated a lipid extract of Perna canaliculus (Lyprinol) and detected furan fatty acids (F-acids). These naturally but rarely detected fatty acids show potent radical-scavenging ability and are essential constituents of plants and algae. Based on these data, it has been proposed that F-acids could be potential antioxidants, which may contribute to the protective properties of fish and fish oil diets against chronic inflammatory diseases. However, to date, in vivo data to support the hypothesis have not been obtained, presumably due to the limited availability of F-acids. To confirm the in vivo anti-inflammatory effect of F-acids in comparison with that of eicosapentaenoic acid (EPA), we developed a semisynthetic preparation and examined its anti-inflammatory activity in a rat model of adjuvant-induced arthritis. Indeed, the F-acid ethyl ester exhibited more potent anti-inflammatory activity than that of the EPA ethyl ester. We report on the in vivo activity of F-acids, confirming that the lipid extract of the green-lipped mussel includes an unstable fatty acid that is more effective than EPA.

Ruthenium-catalyzed selective monoalkenylation of ortho C-O or C-N bonds of aromatic ketones was achieved. The reaction allowed the direct comparison of the relative reactivities of the cleavage of different carbon-heteroatom bonds, thus suggesting an unconventional chemoselectivity, where smaller, more-electron-donating groups are more easily cleaved. Selective monofunctionalization of C-O bonds in the presence of ortho C-H bonds was also achieved.

Aerogels are highly porous solids formed by replacing the liquid in a gel by air, without changing the original structure. The present cellulose aerogels are made by sublimating the water from a colloidal suspension of cellulose nanofibers. The nanofibers form three-dimensional networks, crosslinked by hydrogen bonds bridging the surface hydroxyl groups and also by mechanical entanglements between nanofibers. Although the studies on aerogels from cellulose nanofiber hydrogels by freeze-drying reported so far had produced small samples, improved cooling techniques that produces larger samples were attempted and the obtained cellulose nanofiber aerogels were impregnated with epoxy resin to fabricate composites. The highly porous structure allowed complete impregnation of resin and translucent composites were produced. The modulus of composites was increased in relation to neat epoxy, but due to high brittleness the ultimate strength was decreased. This is likely to be caused by nanofiber agglomerations of uneven pore sizes acting as stress concentrators. The evaluation of the mechanical properties of composites serves as an indirect way to assess the quality of the aerogels produced.

We report here the ruthenium-catalyzed selective monoarylation of aromatic ketones bearing two ortho carbon-heteroatom (O or N) bonds. Under the newly developed catalyst system consisting of RuHCl(CO)(PPr), CsF, and styrene, the C-O arylation of 2',6'-dimethoxyacetophenone with a phenylboronate gave the C-O monoarylation product selectively. The selective C-O monoarylation was applicable to a variety of arylboronates and aromatic ketones and proceeds with high regio- and chemoselectivities. A formal synthesis of altertenuol was also achieved using the C-O monoarylation of an aromatic ester as a key step.

A catalyst system consisting of RuHCl­(CO)­(P i Pr3)2, CsF, and a styrene derivative was found to be applicable to selective monoarylation of aromatic ketones via ortho C–H bond cleavage. The reaction of 2′-methoxyacetophenone with arylboronates gave C–H arylation products without cleaving the ortho C–O bond. Acetophenone was also converted to monoarylation products with high selectivity. Cyclohexanone was found to be an effective solvent for the C–H arylation using the catalyst system.

No abstract

No abstract

Tetraarylanthracenes containing several fluoro groups were synthesized using the ruthenium-catalyzed C–O or C–F arylation with arylboronates and their structural and spectroscopic studies were conducted. The RuH2(CO)(PPh3)3-catalyzed C–O arylation of aromatic ketones was found to be effective for the introduction of aryl groups containing multiple fluoro groups. Anthracenes possessing fluorinated aryl groups were prepared in two steps from 1,4,5,8-tetramethoxyanthraquinone by C–O arylation and reduction of the carbonyl groups. A tetraphenylanthracene containing a fluorinated anthracene moiety was also prepared using C–F phenylation of octafluoroanthraquinone. Single-crystal X-ray diffraction analysis showed that the positions of fluoro groups on the tetraarylanthracenes lead to notable difference in the crystal packing structures. The larger difference between the tetraarylanthracenes was observed in the fluorescence spectra in the solid state than those in chloroform.