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Sea buckthorn leaf tea, an emerging potential functional beverage product, has not yet had appropriate product standards and corresponding quality evaluation methods, and its poor taste directly affects the acceptance of the population, thus limiting its market consumption potential. In this study, two major packaging forms of sea buckthorn leaf tea available in the Chinese market were selected. The contents of total phenolics, total flavonoids, and 10 phenolic compounds, as well as the in vitro antioxidant capacity and sensory characteristics of sea buckthorn leaf tea were analyzed. Results showed that the quality of sea buckthorn leaf tea in the Chinese market varied widely. The total phenolic content, total flavonoid content, antioxidant activity, and consumer acceptance of bagged sea buckthorn leaf tea were higher than those of bulk sea buckthorn leaf tea. Multifactorial statistical analysis showed that the taste astringency of sea buckthorn leaf tea was closely related to ellagic acid and isorhamnetin‐3‐O‐neohesperidin. Furthermore, isorhamnetin‐3‐O‐neohesperidin had a greater effect on the antioxidant activity of sea buckthorn leaf tea. Therefore, ellagic acid and isorhamnetin‐3‐O‐neohesperidin can be used as potential quality markers for sea buckthorn leaf tea. This work provides a reference for taste improvement and quality control of sea buckthorn leaf tea. [ABSTRACT FROM AUTHOR]

Sapphyrin is a pentapyrrolic expanded porphyrin with a 22π aromatic character. Herein, we report the synthesis of a 20π antiaromatic sapphyrin isomer 1 by oxidative cyclization of a pentapyrrane precursor P5 with a terminal β‐linked pyrrole. The resulting isomer 1, containing a mis‐linked bipyrrole unit in the skeleton, exhibits a reactivity for further oxidation due to the distinct antiaromatic electronic structure, affording a fused macrocycle 2, possessing a spiro‐carbon‐containing [5.6.5.6]‐tetracyclic structure. Subsequent treatment with an acid afforded a weakly aromatic pyrrolone‐appended N‐confused corrole 3, and thermal fusion gave a [5.6.5.7]‐tetracyclic‐ring‐embedded 14π aromatic triphyrin(2.1.1) analog 4. The cyclization at the mis‐linked pyrrole moiety of P5 played a crucial role in synthesizing the antiaromatic porphyrinoid susceptible to facile transformation to novel porphyrinoids with variable aromaticity. [ABSTRACT FROM AUTHOR]

Bi5Ti3FeO15 (pentabismuth trititanium iron pentadecaoxide), which is a multiferroic four‐layer Aurivillius phase compound, has received much attention in recent years. However, three mutually inconsistent orthorhombic space groups, i.e. A21am, Fmm2 and Pnn2, have been reported for the room‐temperature phase of Bi5Ti3FeO15 by X‐ray and neutron diffraction investigations. Here, electron diffraction results are presented and discussed for the first time to unambiguously clarify the room‐temperature space group of ceramic Bi5Ti3FeO15. It has been found that all the observed reflections from the ceramic agree with those expected in A21am, while the observed reflections 011, 013 and 015 should be forbidden in the case of Fmm2, and no 107 and 109 reflections were observed although allowed for Pnn2. The present study has demonstrated that the space group of Bi5Ti3FeO15 ceramic is A21am rather than Fmm2 or Pnn2, an identification that proved to be a challenge for X‐ray diffraction. On the basis of the space group A21am, the lattice parameters of the Bi5Ti3FeO15 ceramic were calculated from its X‐ray diffraction data. [ABSTRACT FROM AUTHOR]

The saccharide-based chiral bifunctional thiourea-phosphines were developed as chiral organocatalysts for the intramolecular Morita-Baylis-Hillman reaction of ω-formyl-enones. With only 2 mol% of thiourea-phosphine catalyst 3c, chiral functionalized cyclohexenes were achieved under mild reaction conditions with excellent yields and enantioselectivities. [ABSTRACT FROM AUTHOR]

The direct preparation of a kind of fluorinating reagent 1 [F-TEDA-N(SO2Ph)2] was realized in high yield via the complexation of N-fluorobenzenesulfonimide (NFSI) with 1-(chloromethyl)-1,4-diazabicyclo[2.2.2]octan-1-ium N′, N′-bis-(benzenesulfonylimide) salt. In its fluorination to oxindoles, the fluorinating products 6 were afforded in moderate to high yields. [ABSTRACT FROM AUTHOR]

Z and E configuration 4-aryl-but-2-en-1-ols were isolated from several terrestrial plants, and ( Z)-4-aryl-but-2en-1-ols were found to have choleretic activity. Strategies have been reported to synthesize ( E)-4-aryl-but-2-en-1ols with high selectivity. However, there is no method to obtain ( Z)-4-aryl-but-2-en-1-ols with high selectivity now. We developed a Suzuki-Miyaura cross-coupling reaction of 1,2-oxaborol-2(5 H)-ols with benzyl bromides to synthesize ( Z)-4-aryl-but-2-en-1-ols, the products were obtained in up to 94% isolated yield. [ABSTRACT FROM AUTHOR]

A class of bifunctional phosphinothioureas derived from saccharide was developed as new organocatalysts for the enantioselective Morita-Baylis-Hillman reaction between acrylates and aldehydes. With 10 mol% of glucose-based phosphinothiourea 1d, the allylic alcohols were obtained in up to 96% yield and 83% ee under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Moral identity is an important moral variable which has positive moral functions, such as contributing to prosocial behaviours, reducing antisocial behaviours, and resisting the risk factors of antisocial behaviours. However, little is known about the neural correlates of moral identity and the neural basis of the effect of moral identity on the risk factors of antisocial behaviours, including moral disengagement. In this study, we explored these issues in 142 college students by estimating the regional homogeneity (ReHo) through resting‐state functional magnetic resonance imaging (fMRI). The whole‐brain correlation analyses found that higher internalized moral identity was correlated with higher ReHo in the precuneus. Furthermore, the ReHo in the precuneus was negatively correlated with moral disengagement, suggesting positive moral functions of the neural mechanisms of moral identity. These findings deepen our understanding of individual differences in moral identity and provide inspiration for the education of moral identity and the intervention for moral disengagement from the perspective of the brain. [ABSTRACT FROM AUTHOR]

Tribocatalysis is vitally important for electrochemistry, energy conservation, and water treatment. Exploring eco‐friendly and low‐cost tribocatalysts with high performance is crucial for practical applications. Here, the highly efficient tribocatalytic performance of FeOOH nanorods is reported. The factors related to the tribocatalytic activity such as nanorod diameter, surface area, and surface roughness are investigated, and the diameter of the FeOOH nanorods is found to have a significant effect on their tribocatalytic performance. As a result, under ultrasonic excitation, the optimized FeOOH nanorods exhibit superior tribocatalytic degradation toward rhodamine B (RhB), acid orange 7, methylene blue, methyl orange dyes, and their mixture. The RhB and mixed dyes are effectively degraded within 20 min (k = 0.179 min−1) and 35 min (k = 0.089 min−1), respectively, with the FeOOH nanorods showing excellent reusability. Moreover, antibiotics, such as tetracycline hydrochloride, phenol, and bisphenol A are efficiently degraded. Investigation of the catalytic mechanism reveals that the friction‐generated h+ as well as these yielded •OH and •O2− active radicals participate in the catalytic reaction. This work not only shed light on the design of high‐performance tribocatalyst but also demonstrates that by harvesting mechanical energy, the FeOOH nanorods are promising materials for removing organic contaminants in wastewater. [ABSTRACT FROM AUTHOR]