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Objective: To find, prepare and identify a new oxyphenisatine di（acetate） analogue. Methods: A suspected derivative of oxyphenisatine di（acetate） was found by high-performance liquid chromatography-quadrupole-time-of-flight-mass spectrometry during the routine screening of weight loss healthcare product. The compound was isolated and purified by column chromatography, and the possible structures were inferred from the information of isotope mass spectra, secondary ion mass spectra, one-dimensional and two-dimensional NMR spectra. Finally, all possible structures were prepared by de novo synthesis strategy, and their fine structures were confirmed by spectral comparison. Results： The compound was identified as 5-Cl oxyphenisatine di（acetate）, a new type of oxyphenisatine di（acetate）, which has not been approved as food additives. Conclusion: The toxicological and pharmacological effects of this compound are not clear and should be of concern to regulators. The mass spectrometric fragmentation rule and the de novo synthesis of doubtful structures of these compounds will be beneficial to confirm the fine structure of new compounds.

ObjectiveThis study aimed to achieve rapid qualitative and quantitative analysis of the respective contents of glutamine （Gln） enantiomers in functional foods by establishing a water-soluble lanthanide shift reagent-identified method based on the 1H-qNMR technique.MethodsThe internal standard disodium terephthalate was added to the samples dissolved in ultrapure water. After vertexing and centrifuging， an appropriate amount of supernatant was taken into the NMR tube with deuterium water as a field-locking solvent and the water-soluble lanthanide shift reagent samarium （Ⅲ）-propylenediaminetetraacetate as the chiral selector. The 1H-NMR spectrum was collected by a 600 MHz nuclear magnetic resonance spectrometer for the direct determination of the contents of Gln enantiomers in functional foods.ResultsThe Gln enantiomers and DT quantitative peaks were well-separated. The mass concentration of D- and L-glutamine has a good linearity in the range of 100.0-2 000.0 µg/mL with R2>0.99. The limit of detection was 30.0 µg/mL， and the limit of quantification was 100.0 µg/mL. The average recovery rates obtained from standard addition methods were between 94.27% and 116.07% with the relative standard deviations （n=6） being 0.18%-1.84%.ConclusionThis method offers high recovery， good repeatability， and a simple pretreatment process， and the sample test can be completed within 15 min. The testing of different dosage forms of functional foods purchased from the supermarket platform revealed that the enantiomeric purity of Gln in the samples was ≥99%. No significant difference was observed between this method and high-performance liquid chromatography （P>0.05） in the determination of total Gln. The method can provide a practical technique for the rapid detection of the contents of glutamine enantiomers.

为了解决食用油在储存过程中因发生各种变化而造成的品质下降问题，介绍了一种食用油的锁养保鲜生产工艺，包括全工段恒温灌装、充氮灌装和抗紫外瓶包装。实践证明，全工段恒温灌装有效避免了灌装油温过高产生负压造成的瓶内缩吸瘪，减少了标签不平整情况的发生；充氮灌装使食用油包装瓶内顶空残氧量低于6％，产品残氧量指标稳定；以色母为抗紫外助剂，制成的食品级食用油包装瓶可防止紫外线对食用油品质的影响。采用此生产工艺，可以有效提高食用油的品质并延长储存期。 In order to solve the problem of degradation of the quality of edible oil due to various changes that occur during the storage process, a fresh-keeping production technology of edible oil was introduced, including constant temperature filling in the whole section, nitrogen filling and UV resistant bottle packaging. The practice showed that the constant temperature filling in the whole section could effectively avoid the bottle shrinkage caused by the high filling oil temperature and negative pressure, and reduce the occurrence of uneven labels. Nitrogen filling could make the residual oxygen content in the processed edible oil bottle less than 6%, and the product residual oxygen index stable. The food grade edible oil packaging bottle made of color masterbatch as an anti-ultraviolet additive could prevent the influence of ultraviolet rays on the quality of edible oil. The use of this production process can effectively improve the quality of edible oil and extend the storage period.

ObjectiveA qualitative and quantitative method has been established to rapidly determine carnitine enantiomers in dietary supplement by 1H-nuclear magnetic resonance combined with chiral lanthanide shift reagents （CLSR-1H qNMR）.MethodsPyrazine acted as internal standard was added to the samples dissolved in d4-methanol. After vortexing， ultrasonic-assisted extraction and centrifugation， an appropriate amount of supernatant and chiral lanthanide shift reagent （CLSR） Eu（thfc）3 were added to the NMR tube for directly determination.ResultsThe linearity range of L-carnitine was 16.3～4 800 µg/mL with correlation coefficient （r）>0.99. The limit of detection （LOD） was 24.5 mg/kg， and the limit of quantification （LOQ） was 73.5 mg/kg. While the linearity range of D-carnitine was 10.6～530 µg/mL with r>0.99. The LOD was 27.5 mg/kg， and the LOQ was 82.5 mg/kg. Recovery rates obtained from spiked samples were between 95.9% and 114.6% with the RSDs （n=6） of 3.31%~6.12%. Tests on capsules， milk tea， coffee powder and tablet from online shopping that claimed to have weight-loss effects failed to detect D-carnitine.ConclusionThis method is simple， rapid and sensitive. And the sample test could be completed within 25 min， which could provide a theoretical basis for rapidly detection of carnitine enantiomers.

ObjectiveTo develop a method that can quickly determine the absolute content of boron in food by quantitative nuclear magnetic resonance （qNMR） analysis technology.MethodsThe signal area is directly proportional to the content of boron causing the peak under certain sample-acquired condition. Natural quartz NMR tubes （boron content 0.999 9. The LODs and the LOQs were 20 and 60 mg/kg， respectively. The recoveries ranged from 90.3% to 102.1%. The precision between days was 1.26%-1.61%.ConclusionThere are some good potential application prospects as for its simple pretreatment， quick measurement process， and accurate experimental result.

Nitrogen-rich heterocyclic compounds have a profound impact on human health. Despite the numerous synthetic methods, diversified, step-economic, and general synthesis of heterocycles remains limited. C-H bond functionalization catalyzed by rhodium(iii) cyclopentadienyls has proven to be a powerful strategy in the synthesis of diversified heterocycles. Herein we describe rhodium(iii)-catalyzed sp 2 and sp 3 C-H activation-oxidative annulations between aromatic substrates and 1,3-enynes, where alkenyl-to-allyl 1,4-rhodium(iii) migration enabled the generation of electrophilic rhodium(iii) π-allyls via remote C-H functionalization. Subsequent nucleophilic trapping of these species by various sp 2 -hybridized N-nucleophiles delivered three classes (external salts, inner salts, and neutral azacycles) of five-membered azacycles bearing a tetrasubstituted saturated carbon center, as a result of [4 + 1] annulation with the alkyne being a one-carbon synthon. All the reactions proceeded under relatively mild conditions with broad substrate scope, high efficiency, and excellent regioselectivity. The synthetic applications of this protocol have also been demonstrated, and experimental studies have been performed to support the proposed mechanism.

Cp*Rh III /Ir III complexes are known to play important roles in both C-H activation and transfer hydrogenation (TH). However, these two areas evolved separately. They have been integrated in redox- and chemodivergent coupling reactions of N-pyridylanilines with enones. The iridium-catalyzed coupling with enones leads to the efficient synthesis of tetrahydroquinolines through TH from i PrOH. Counterintuitively, i PrOH does not serve as the sole hydride source, and the major reaction pathway involves disproportionation of a dihydroquinoline intermediate, followed by the convergent and iterative reduction of quinolinium species., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)