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A strategically novel synthetic method for the fluoroarylation of allenic ester was developed that enables the expedient construction of a host of β-fluoroalkyl-containing cinnamate derivatives. The reaction proceeds through visible-light-promoted gold redox catalysis, occurs smoothly under very mild reaction conditions, accommodates a large variety of functional groups, and more importantly allows the incorporation of fluorine and aryl groups with excellent regio- and stereoselectivity. The concomitant activation mode for both the allene motif and the hydrogen fluoride is key for the success of the reaction.

Background In recent years, there has been growing evidence that vitamin D deficiency is associated with the development and progression of chronic heart failure (CHF). Hypothesis Additional supplementation of vitamin D may have protective effects in patients with CHF. Methods We searched PubMed, Embase, and Cochrane databases through June 2015 and included 7 randomized controlled trials that investigated the effects of vitamin D on cardiovascular outcomes in patients with CHF. Then, we performed a meta-analysis of clinical trials to confirm whether vitamin D supplementation is beneficial in CHF patients. The weighted mean difference (WMD) and 95% confidence interval (CI) were calculated using fixed- or random-effects models. Results Our pooled results indicated that additional supplementation of vitamin D was not superior to conventional treatment in terms of left ventricular ejection fraction, N-terminal pro-B-type natriuretic peptide, and 6-minute walk distance. Moreover, vitamin D supplementation was associated with significant decreases in the levels of tumor necrosis factor-α (WMD: −2.42 pg/mL, 95% CI: −4.26 to −0.57, P < 0.05), C-reactive protein (WMD: −0.72 mg/L, 95% CI: −1.42 to −0.02, P < 0.05), and parathyroid hormone (WMD: −13.44 pg/mL, 95% CI: −21.22 to −5.67, P < 0.05). Conclusions Vitamin D supplementation may decrease serum levels of parathyroid hormone and inflammatory mediators in CHF patients, whereas it has no beneficial effects on improvement of left ventricular function and exercise tolerance.

We report the asymmetric vinylogous Mannich reactions (VMRs) of N-Boc-2-tert-(butyldimethylsilyloxy)pyrrole (TBSOP) with N-tert-butanesulfinylimines. The reaction is highly anti-diastereoselective and shows good generality for the direct construction of a variety of vicinal anti-diamine motifs that are found in a number of biologically active alkaloids and medicinal agents. A VMR adduct was elaborated in six steps into the 1-aminopyrrolizidine alkaloid (+)-absouline, which constitutes the second and also the most efficient total synthesis of the natural enantiomer of the title alkaloid.

Two new-skeleton compounds, sarcaboside A (1) together with its artifact sarcaboside B (2), were isolated from the whole plant of Sarcandra glabra. Their structures were elucidated on the basis of extensive spectroscopic analysis as well as HR-ESI-MSn study.

Tonghaosu and its analogs are a class of structurally interesting spiroketal enol-ether compounds. A practical route to furandiol, a key intermediate for their syntheses, was developed. Using Friedel-Crafts benzoylation of 3-(2-fury I) propyl acetate, a diarylketone was obtained in high yield, which was further transformed into corresponding furandiol by reduction with NaBH4 in basic medium with simultaneous ester hydrolysis. The furandiol was then cyclized into the desired spiroketal enol-ether compound in the presence of CuSO4 5H2O.

Cohesive (Group C) particles have been widely used in various industries. To handle and process such fine particles, a clear understanding of the flow behavior and interparticle force, is needed. To achieve that objective, a Laser Doppler Anemometer system was used to measure particle velocity, fluctuating velocity, and size and extent of agglomeration or cluster formation of particles in a dilute gas/fine oil shale particle flow system with particle density of 2,082 kg/m3, average particle volumetric concentration of 1.5%, and average particle mass flux of about 100 kg/m2·s in a controlled-moisture environment. The flow behavior of the particles was also studied for a mixture of 99% shale particles and 1% antistatic agent (Larostat powder, a quaternary ammonium compound) to examine the role of electrostatic force in gas/cohesive particle flow behavior. The addition of Larostat powder significantly reduced the electrostatic force and, in turn, made Group C particles behave similar to Group A or in some cases to Group B particles. In addition, our experimental data showed that the Maxwellian distribution function is a reasonable assumption to describe the velocity probability density function of the shale particles with or without antistatic agents.

Two new-skeleton compounds, sarcaboside A (1) together with its artifact sarcaboside B (2), were isolated from the whole plant of Sarcandra glabra. Their structures were elucidated on the basis of extensive spectroscopic analysis as well as HR-ESI-MSn study.