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Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

Science China Chemistry 2025年第1期 233-240页

作者： Peipei Liu Yantong Li Meng-Xiang Wu Hao Kang Xiao-Li Zhao Lin Xu Linlin Liu Xiaodong Li Junfeng Fang Zhiwei Fang Ya Cheng Hai-Bo Yang Huakang Yu Xueliang Shi State Key laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

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Detection of Total Phenols, Essential and Toxic Elements in Latvian Whole Grain Bread

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Journal of Chemistry and Chemical Engineering 2012年第1期6卷 1-6页

作者： Natalia Bobere Anton Podjava Ida Jakobsone Food Chemistry Centre Department of Chemistry University of Latvia Riga L V- 1013 Latvia laboratory of chromatography and massspectrometry Department of Chemistry University of Latvia Riga L V-1013 Latvia

A survey was carried out with the aim of assessing the level of the total phenolic compounds （TPC）, essential （Na, K, Ca, Mg, Cu, Zn） and toxic （Cd and Pb） elements in 10 Latvian whole grain rye and/or wheat flour bread samples, obtained from the local market. The quantities of the TPC were determined by spectrophotometry. Mineral content was determined by flame photometry, flame atom absorption spectrometry （FAAS） and electrothermal atomic absorption spectrometry （ETAA） after wet digestion in concentrated HNO3. The values were comparable to the literature data. The average content in all the samples was （on a basis of weight of the product） 547 ± 28 mg/100 g for Na; 280 ±20 mg/100 g for K; 32 ± 2 mg/100 g for Ca; 88 ±5 mg/100 g for Mg; 0.49 ± 0.09 mg/100 g for Cu; 1.6 ±0.2 mg/100 g for Zn. Both Pb and Cd were determined below the limit of detection （LOD 5 0.10 mg/100 g）. The LOD values were determined for each element. The TPC content in defatted samples was slightly lower than the non-defatted ones, showing the dependence on the sample preparation. The calculated average levels of the elements were compared with the maximum levels recommended or regulated by the national legislation.

关键词： Essential and toxic elements whole grain bread flame photometry FAAS ETAA total phenols spectrophotometry.

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[Current advances in the analysis of free RNA modified nucleosides by high performance liquid chromatography-tandem mass spectrometry]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 3-12页

作者： Lyu-Ye Zhang Wei-Bing Zhang Hai-Lin Wang State Key laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. Shanghai Key laboratory of Functional Materials Chemistry School of Chemistry & Molecular Engineering East China University of Science and Technology Shanghai 200237 China. State Key laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 3. University of Chinese Academy of Sciences Beijing 100049 China. University of Chinese Academy of Sciences Beijing 100049 China.

Post-transcriptional ribonucleic acid (RNA) modifications play crucial roles in regulating gene expression, with both eukaryotic and prokaryotic RNA exhibiting more than 170 distinct and ubiquitous modifications. RNA turnover generates numerous free nucleosides, including unmodified nucleosides and a variety of modified ones. Unlike unmodified nucleosides, modified nucleosides are not further degraded or used in the salvage-synthesis pathway owing to a lack of specific enzymes, which leads to the cytosolic accumulation or cellular efflux of modified nucleosides. These modified nucleosides can act as signaling molecules that regulate downstream pathways once transported to the extracellular space; alternatively, they are metabolized in the bloodstream and excreted in urine. Metabolized modified nucleosides are altered by cellular stress responses and mediate abnormal physiological states. Changes in the urinary and blood levels of modified nucleosides associated with cancer can serve as biomarkers for disease. Therefore, identifying and accurately quantifying nucleosides is vital for understanding RNA degradation and associated patterns of nucleoside metabolism. Such analyses are helpful when studying the biological functions and potential clinical applications of modified nucleosides. In this regard, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) offers significant advantages in terms of sensitivity, selectivity, and efficiency, and has been widely used to analyze DNA and RNA nucleosides/nucleotides and their analogues. Multiple MS detection patterns and quantification methods have been established to detect nucleosides in biological samples, including cultured cells, urine, blood, and tissue samples. However, the development of an accurate HPLC-MS/MS method faces several challenges. Firstly, the presence of a complex biological matrix that contains macromolecules, small molecules, and salts can interfere with analysis. Salts and co-elu

关键词： RNA modifications high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) metabolite analysis methylated nucleosides

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Capillary electrophoretic study on UDP-sugars in cells

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Science China Chemistry 2000年第1期43卷 85-93页

作者：许国旺 R.Lehmann 路鑫 H.M.Liebich 张玉奎卢佩章 National Chromatographic R. & A. Center Laboratory of Chromatography Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116011 China Medizinische Universitaetsklinik Tuebingen Tuebingen 72076 Germany

Glucose is an important regulator of cell growth and metabolism. Uridine diphosphate sugars (UDP-sugars), as the intermediate products of metabolism, play pivotal roles as precursors in the synthesis of complex carbohydrates and glycolipids as well as lectose. It is very important to study their metabolism in cells in clinical biochemistry. A capillary electrophoretic method has been developed for the analysis of UDP-sugars and nucleotides. By using an uncoated capillary (70cm×50μm) and 20 mmol/L borax buffer (pH 9), 4 important UDP-sugars can be analyzed in 15 min at 22 kV with satisfactory precision and sensitivity. The developed method has been applied to analyze UDP-sugars concentrations in lymphocytes, fibroblasts and mesangial cells, and the results show it not only is much better than HPLC method, but also can be used to measure the energy charge of cells.

关键词： cells glucose capillary electrophoresis UDP-sugars hexosamines.

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Determination of p-Toluenesulfonic Acid in Water-Insoluble Drugs by Ion chromatography

Determination of p-Toluenesulfonic Acid in Water-Insoluble D...

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第十届全国生物医药色谱及相关技术学术交流会

作者： Liao Dongli Pan Guangwen Xu Qun Liang Lina Jeffrey Rohrer chromatography and Mass Spectrometry Division Thermo Fisher Scientific

＜正＞p-Toluenesulfonic acid is an organic acid,and widely used in pharmaceutical industry as counter-ions for basic drugs because of its strong acidic and hydrophilic ***,it is important to determine the content of p...

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Separation of Intact Monoclonal Antibody Sialylation Isoforms by pH Gradient Ion Exchange chromatography

Separation of Intact Monoclonal Antibody Sialylation Isoform...

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第十届全国生物医药色谱及相关技术学术交流会

作者： Dai Zhenyu Xu Qun Lina Liang Jeffrey Rohrer chromatography and Mass Spectrometry Division Thermo Fisher Scientific

Glycosylated proteins,including erythropoietins,monoclonal antibodies,various hormones,constitute major approved therapeutic biological *** acid is important to cell recognition and migration and critical to circulation half life of the protein as exampled by therapeutic protein rh *** monitoring protein glycosylation,including sialylation,is important for both glycoprotein characterization and quality control *** oligosaccharide profiling（both fluorescently labeled and unlabeled）requires releasing the glycan from the protein and thus is time and labor *** electrophoresis,currently available technique for intact protein sialylation profiling,may not provide enough *** an analysis method with both convenience and higher resolution is needed for protein sialylation monitoring.

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[Determination of 12 halogenated organic pollutants in edible fish by ultra performance liquid chromatography-high resolution mass spectrometry combined with ultrasound-assisted extraction and gel permeation chromatography purification]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 68-77页

作者： Yi-Zhe Zhu Rui-Fen Zheng Zi-Hao Fan Ling Liu Jing-Yao Ye Kai Wang Cai-Ming Tang Research Center for Eco-Environmental Engineering Dongguan University of Technology Dongguan 523808 China. Guangdong Key laboratory of Environmental Resources Utilization and Protection Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China.

Halogenated organic pollutants (HOPs) have attracted considerable attention owing to their persistence, bioaccumulation, and toxicity. The development of methods to detect HOPs in fish is challenging owing to the compositional complexity of fish matrices, which contain high levels of lipids and relatively low concentrations of HOPs. In addition, the lipophilicity of most HOPs renders their extraction difficult. Moreover, the simultaneous determination of multiple HOPs to achieve the high-throughput screening of these analytes is complex. In this study, a reliable and efficient pretreatment method based on ultrasound-assisted extraction, gel permeation chromatography purification, and ultra performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) was developed for the determination of 12 HOPs in edible fish. The procedures of sample extraction and purification and LC-HRMS detection parameters were optimized to improve the performance of the method. Fresh fish samples were thoroughly rinsed with water, and non-edible parts, including the skin, bones, and phosphorus, were removed. The fish were weighed, cut into small pieces, and vacuum freeze-dried for 48 h. Subsequently, a freeze grinder was used to grind the dried fish into a fine powder. Exactly 2 g of the fish powder was weighed, fortified with isotope-labeled internal standards of the HOPs, and allowed to stand for 5 min. Methanol-acetonitrile (1∶1, v/v) was then added, followed by vortex mixing and ultrasonication. After centrifugation, the supernatant was transferred to a fresh tube. The extraction process was repeated twice and all extracts were combined. The extract was evaporated under a gentle nitrogen flow and redissolved in a mixture of ethyl acetate-cyclohexane (1∶1, v/v). The sample mixture was cleaned using gel permeation chromatography, and the eluate was collected and concentrated under a nitrogen flow. Sample residuals were reconstituted with water-methanol (1∶1, v/v) prior to

关键词： edible fish gel permeation chromatography (GPC) halogenated organic pollutants (HOPs) ultra performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS)

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Phenolic compounds in peel,seed and cold pressed pink pepper(Schinus terebinthifolia R.)oil and bioaccessibility of peel using a digestion model with intestinal barrier simulation

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Food Bioscience 2022年第5期49卷 701-709页

作者： Tuania Soares Carneiro Maria da Conceiçao Prudencio Dutra D´ebora Andrade Lima Ana Júlia de Brito Araújo Patrícia Beltrao Lessa Constant Marcos dos Santos Lima Federal University of Sergipe Department of Food TechnologyPROCTASao Crist´ovaoSEBrazil Federal Institute of Sertao Pernambucano Department of Food TechnologyLiquid Chromatography LaboratoryJardim Sao Paulo-CEP56314-522PetrolinaPEBrazil

Pink pepper-PP(Schinus terebinthifolius R.)has been used as a flavoring agent,an antioxidant,and a natural *** have focused on obtaining essential oils and antioxidants from the whole *** studies have evaluated the quantification of phenolics and bioaccessibility of the fruit *** quantification of bioactive compounds from PP oil obtained by cold pressing are also *** this work,21 phenolics(HPLC-DAD)and antioxidant capacity(AOX)were quantified in peel,seed and cold-pressed oil of PP,in two *** bioactive and antioxidant potential of the fractions studied in PP were peel>oil>*** peel possessed the richest fraction;in particular,gallic acid(2819-3129 mg/kg),procyanidin B2(720-760 mg/kg),catechin(528-594 mg/kg),kampferol-3-glucoside(166-184 mg/kg)peonidin-3-O-glucoside(55.3-58.5 mg/kg)and pelargonidin 3-O-glucoside(17.8-20.2 mg/kg),and high *** was the second richest fraction with highlight gallic acid(735 mg/kg),catechin(103-105 mg/kg),procyanidin A2(19 mg/kg)and chlorogenic acid(5 mg/kg).PP peels were submitted to in vitro digestion model with intestinal barrier simulation,where hesperidin(23352%),naringenin(273%)and catechin(84%)were the most bioaccessible *** present study shows that the PP peel has the greatest bioactive ***,obtaining the oil by cold pressing fruit is an alternative to be explored.

关键词： Pink pepper Lipid technology Phytochemicals Bioaccessibility

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[Advances in molecular networking technology for discovering emerging contaminants and transformation products]

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Se pu = Chinese journal of chromatography 2025年第1期43卷 33-42页

作者： Xiao-Mei Tan Yu-Wei Zhang Zhao-Yu Jiao Nan-Yang Yu Si Wei State Key laboratory of Pollution Control & Resource Reuse School of Environment Nanjing University Nanjing 210046 China.

Emerging contaminants and their transformation products are widely distributed in the environment. These pollutants carry unknown risks owing to their persistence, migration, and toxicity. The wide variety and complex structures of these substances render them difficult to identify using only target analysis. Suspect screening analysis can identify more substances than target analysis in a single run. However, this analysis method is based on limited data and cannot meet the growing demand for compound identification, especially for emerging contaminants and their transformation products with unknown information. The development of high-resolution mass spectrometry technology has promoted the applications of nontarget analysis in the environmental field, especially for identifying unknown transformation products. At present, the challenges of nontarget analysis include the difficulty of finding compounds of interest and their transformation products from complex data. Molecular networking calculates the similarity between mass spectra based on an improved cosine similarity algorithm. This method can cluster molecular families with similar structures, achieve visualization and a collection of massive mass spectral datasets, and promote the annotation of pollutants through networks and communities. Molecular networking can globally organize and systematically interpret complex tandem mass spectral datasets, providing a new direction for nontarget analysis. This technology was first used in proteomics and gradually introduced into metabolomics for the discovery of new natural products. Recently, it has been introduced into the environmental field for the study of various man-made chemicals, particularly for the discovery of emerging contaminants and their transformation products. In this paper, we introduce a molecular networking analysis method based on high-resolution tandem mass spectrometry and describe its applications in the nontargeted screening of emerging cont

关键词： emerging contaminants high-resolution tandem mass spectrometry molecular networking transformation products

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Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation

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Traditional Medicine Research 2025年第2期10卷 1-15页

作者： Xu Liang Ni-Hui Zhang Zhi-Lai Zhan Guang-Lu Chang Yan Gao Xia Li Wen-Yuan Gao School of Pharmaceutical Science and Technology Faculty of MedicineTianjin UniversityTianjin 300193China State Key laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs China Academy of Chinese Medical SciencesBeijing 100700China Key laboratory of Modern Chinese Medicine Resources Research Enterprises Tianjin 300402China

Background:Rosa chinensis *** Rosa rugosa *** not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional *** two plants have some differences in efficacy,but the flower buds are easily confused for similar *** addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal ***,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography ***,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large *** compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and ***:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the *** principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four *** least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavon

关键词： Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics chemometrics multiple component quantification quality evaluation

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