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The anti-inflammatory activities of fucoxanthin, a marine carotenoid derived from the macroalgae and microalgae, have been demonstrated in the previous studies. However, the effect of fucoxanthin on ulcerative colitis (UC), an inflammatory bowel disease, was still unclear. In this study, we evaluated the in vivo anti-inflammatory effect of fucoxanthin on dextran sulfate sodium(DSS)-induced colitis in mice. Fucoxanthin at the doses of 50 and 100 mg/kg/day significantly protected against DSS-induced gradual loss of body weight, exhibited inhibitory effects on the DSS-induced increase of disease activity index and colon shortening. Moreover, fucoxanthin treatment resulted in a marked amelioration of the histological damage in the colon, and reduced the colonic PGE2 levels in colitic mice. In addition, the DSS-induced overexpressions of inflammation-related molecules including COX‐2 and NF-κB were significantly decreased in fucoxanthin-treated mice. These finding suggested that the use of fucoxanthin provides a new and attractive alternative to control UC. [ABSTRACT FROM AUTHOR]

A palladium(II)‐catalyzed acylation of 2‐phenylpyridine N‐oxides via ortho‐selective C−H activation at phenyl ring is developed using benzyl alcohols or α‐oxocarboxylic acids as the acylation reagents under mild conditions. The two reaction protocols exhibited complementary substrate scopes, and are tolerated to a variety of 2‐phenylpyridine N‐oxide substrates with high yield and selectivity. Mechanism studies indicated that this acylation reaction includes a radical process via acyl radical. [ABSTRACT FROM AUTHOR]

A cooperative CuBr2 and tert-butyl hydroperoxide (TBHP) system allowed for the highly stereoselective dibromination and bromohydroxylation reactions of (diphenylphosphoryl)allenes under mild (room temperature) and operationally simple conditions. These reactions selectively proceeded through either a dibromination or bromohydroxylation process and are characterized by their broad substrate scope (22 examples), their step economy, and ability to be carried out on a gram scale. This method offers a useful protocol to access allyl bromides and alcohols. Moreover, synthetic applications of the dibromination products include a Suzuki–Miyaura cross-coupling reaction and copper-catalyzed cascade process, which could also afford various important derivatives. [ABSTRACT FROM AUTHOR]

Mo8O264− based organic polyoxomolybdate salts of general formula [Hmim]4Mo8O26 (Hmim = 1-hexyl-3-methylimidazolium), [Dhmim]4Mo8O26 (Dhmim = 1,2-dimethyl-3-hexylimidazolium) and [Hpy]4Mo8O26·H2O (Hpy = 1-hexylpyridinium) have been prepared and characterized. These compounds were applied as catalysts for olefin epoxidation using hydrogen peroxide (H2O2) as oxidant in CH3CN. The polyoxomolybdate salts exhibit excellent catalytic performance and are also self-separating, a great advantage for catalyst recycling. The catalysts can be reused for at least 10 runs without significant loss of activity. [ABSTRACT FROM AUTHOR]

The article presents a study which shows that probiotic can reduce the concentration of ammonia in broilers and improve the total protein and globulin content in serum.

Novel copper/B 2 pin 2 -catalyzed difluoroalkylation of methylenecyclopropanes with bromodifluorinated acetates and acetamides via a tandem radical process involving ring-opening/intramolecular cyclization has been reported. This protocol is not only tolerated to a diverse range of substrates but also applicable to the synthesis of useful difluoromethylated compounds. Moreover, the reaction could be performed on a gram scale with a high yield, which opens up the possibility for practical applications.

Neuregulin-1 (NRG1), now in a phase II clinical trial, has beneficial effects on heart failure patients through the activation of ErbB2/ErbB4 receptor pair. To decrease the side effect of NRG1 on activating ErbB3, a mutation screen was carried out to get NRG1 mutants, which have more specific binding to ErbB2/ErbB4 receptor pair. Two CHO stable cell lines were constructed, which express ErbB2/ErbB3 or ErbB2/ErbB4 receptor pair, respectively. The ErbB2/ErbB4 cell line showed similar characteristics in ligand-binding activity and the activation of downstream signaling molecules, such as the AKT and PI3K to the primary neonatal rat ventricular myocytes (NRVM), which endogenously expresses ErbB2/ErbB4. Both cell lines have good dose-response. Thirty-one NRG1 mutants were successfully expressed in Escherichia coli and purified. Their ability to stimulate the downstream signaling was measured by detecting AKT phosphorylation. Some mutants showed more specific activation activity in ErbB2/ErbB4 cells. Further study on five of these mutants demonstrated that the change of the activation activity is associated with that of their binding activities to ErbB2/ErbB4 and ErbB2/ErbB3. Four of the candidates are more specific ligands for ErbB2/ErbB4 activation, and thus may serve as more potent drug candidates for heart failure.

Methyltrioxorhenium(VII) (MTO) readily forms 1:1 adducts with several N-(salicylidene)aniline derived Schiff bases. If the aromatic rings of the N-(salicylidene)aniline ligands display non-donating or electron withdrawing substituent groups, the resulting MTO adducts show good activities in olefin epoxidations. However, steric effects seem to play a major role, leading often to instable o- and m-Schiff base-MTO adducts, while p-substituted Schiff bases usually lead to more stable adducts. In catalysis, electron-withdrawing substituents on the aniline moiety lead to better catalysts than electron donating ones. The gap between good catalysts and instable or non-existing compounds, however, is small. The general tendency, however, that good donors on the Schiff base ligands lead to shorter Re-O(Schiff base) bridges and lower catalytic activity, while the opposite is true with acceptor ligands on the Schiff bases, seems to be quite clear.

Several Schiff-base ligands readily form complexes with methyltrioxorhenium(VII) (MTO) by undergoing a hydrogen transfer from a ligand-bound OH group to a ligand N atom. The resulting complexes are stable at room temperature and can be handled and stored in air without problems. Due to the steric demands of the ligands they display distorted trigonal-bipyramidal structures in the solid state, as shown by X-ray crystallography, with the O(-) moiety binding to the Lewis acidic Re atom and the Re-bound methyl group being located either in cis or trans position to the Schiff base. In solution, however, the steric differences seem not to be maintained, as can be deduced from (17)O NMR spectroscopy. Furthermore, the Schiff-base ligands exchange with donor ligands. Nevertheless, the catalytic behaviour is influenced significantly by the Schiff bases coordinated to the MTO moiety, which lead either to high selectivities and good activities or to catalyst decomposition. A large excess of ligand, in contrast to the observations with aromatic N-donor ligands, is detrimental to the catalytic performance as it leads to catalyst decomposition.