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Six new coumarins from the roots of Toddalia asiatica and their anti-inflammatory activities

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Chinese Journal of Natural Medicines 2023年第11期21卷 852-858页

作者： HE Haoxuan LI Niping FAN Yunqi HUANG Qian SONG Jianguo LV Lixia LIU Fen WANG Lei WANG Qi GU Jihong Science and Technology Innovation Center Guangzhou University of Chinese MedicineGuangzhou 510405China State Key Laboratory of Bioactive Molecules and Druggability Assessment Jinan UniversityGuangzhou 510632China

We reported the discovery of six novel coumarins, toddasirins A–F ( 1 – 6 ), each endowed with modified isoprenyl or geranyl side chains, derived from the roots of Toddalia asiatica. Comprehensive structural elucidation was achieved through multispectroscopic analyses, single-crystal X-ray diffraction experiments, and advanced quantum mechanical electronic circular dichroism (ECD) calculations. Furthermore, the anti-inflammatory activity of these compounds was assessed. Notably, compounds 1 – 3 and 6 demonstrated notable inhibitory effects on nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW 264.7 cells, with 50% inhibitory concentration (IC50) values of 3.22, 4.78, 8.90, and 4.31 μmol·L^(−1), respectively.

关键词： Toddalia asiatica coumarins Anti-inflammatory effects RAW 264.7 cells

Three new coumarins and a new coumarin glycoside from Micromelum integerrimum

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Chinese Journal of Natural Medicines 2021年第8期19卷 621-625页

作者： CAO Nan-Kai CHEN Yue-Mei ZHU Si-Si ZENG Ke-Wu ZHAO Ming-Bo LI Jun TU Peng-Fei JIANG Yong State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China

Three new coumarins,integmarins A–C(1–3),and a new coumarin glycoside,integmaside A(4)were isolated from the leaves and stems of Micromelum *** structures were elucidated on the basis of 1 D and 2 D NMR and MS data,and their absolute configurations were assigned according to the ECD data of the in situ formed transition metal complexes and comparison of experimental and calculated ECD *** 1 and 2 are two rare coumarins with butyl and propyl moieties at the C-6 position;compound 3 is a novel coumarin with a highly oxidized prenyl group,and compound 4 is a rare bisdihydrofuranocoumarin glycoside.

关键词： Rutaceae Micromelum integerrimum coumarins Coumarin glycoside ECD

TMSOTf-catalyzed intramolecular seleno-arylation of tethered alkenes:A novel method for the solid-phase synthesis of dihydrocoumarins and coumarins

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Chinese Chemical Letters 2012年第6期23卷 631-634页

作者： E Tang Wen Li Zhang Yong Gao Xi Gu Key Laboratory of Medicinal Chemistry of Natural Resource （Yunnan University） Ministry of Education China Department of Applied Chemistry Yunnan University Kunming 650091 China

TMSOTf-catalyzed intramolecular seleno-arylation of tethered alkenes was performed using polystyrene-supported succini- midyl selenide as the selenium source. This catalytic process provides an efficient method for the regioselective synthesis of dihydrocoumarins possessing a seleno-functionality, followed by traceless cleavage of selenium linker to provide dihydrocoumar- ins and coumarins in good yields and purifies.

关键词： Lewis acid Seleno-arylation Succinimidyl selenide Solid-phase synthesis Dihydrocoumarins coumarins

L-Proline as an efficient and reusable promoter for the synthesis of coumarins in ionic liquid

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第12期9卷 990-995页

作者： Xiu-hong LIU Ji-cai FAN Yang LIU Zhi-cai SHANG Department of Chemistry Zhejiang University Hangzhou 310027 China

The effect of L-proline as a promoter on the condensation reaction of salicylaldehyde or its derivatives with ethyl acetoacetate in neutral ionic liquid [emim]BF4 was studied. All reactions were carried out under mild reaction conditions and achieved high yields. Moreover, the ionic liquid containing L-proline could be recycled and reused for several times without noticeably decreasing in productivity. The results show that the L-proline-[emim]BF4 system has a potential in contribution to the development of environmentally friendly and inexpensive processes in organic syntheses.

关键词： L-Proline Ionic liquid coumarins Knoevenagel condensation

Two types of coumarins-specific enzymes complete the last missing steps in pyran- and furanocoumarins biosynthesis

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Acta Pharmaceutica Sinica B 2024年第2期14卷 869-880页

作者： Yucheng Zhao Yuedong He Liangliang Han Libo Zhang Yuanzheng Xia Fucheng Yin Xiaobing Wang Deqing Zhao Sheng Xu Fei Qiao Yibei Xiao Lingyi Kong Department of Resources Science of Traditional Chinese Medicines School of Traditional Chinese Pharmacyand State Key Laboratory of Natural MedicinesChina Pharmaceutical UniversityNanjing 210009China College of Bioscience and Biotechnology Hunan Agricultural UniversityChangsha 410128China Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines Department of Natural Medicinal ChemistryChina Pharmaceutical UniversityNanjing 210009China Key Laboratory of Crop Gene Resources and Germplasm Enhancement in Southern China Ministry of AgricultureTropical Crops Genetic Resources InstituteChinese Academy of Tropical Agricultural SciencesHaikou 517317China Institute of Botany Jiangsu Province and Chinese Academy of SciencesNanjing 210014China Department of Pharmacology School of Pharmacyand State Key Laboratory of Natural MedicinesChina Pharmaceutical UniversityNanjing 210009China

Pyran-and furanocoumarins are key representatives of tetrahydropyrans and tetrahydrofurans,respectively,exhibiting diverse physiological and medical ***,the biosynthetic mechanisms for their core structures remain poorly *** we combined multiomics analyses of biosynthetic enzymes in Peucedanum praeruptorum and in vitro functional verification and identified two types of key enzymes critical for pyran and furan ring biosynthesis in *** included three distinct *** prenyltransferases(PpPT1e3)responsible for the prenylation of the simple coumarin skeleton 7 into linear or angular precursors,and two novel CYP450 cyclases(PpDC and PpOC)crucial for the cyclization of the linear/angular precursors into either tetrahydropyran or tetrahydrofuran *** analyses of cyclases indicated that acid/base-assisted epoxide ring opening contributed to the enzyme-catalyzed tetrahydropyran and tetrahydrofuran ring *** possible acid/base-assisted catalytic mechanisms of the identified cyclases were theoretically investigated and assessed using site-specific *** identified two possible acidic amino acids Glu303 in PpDC and Asp301 in PpOC as vital in the catalytic *** study provides new enzymatic tools in the epoxide formation/epoxide-opening mediated cascade reaction and exemplifies how plants become chemically diverse in terms of enzyme function and catalytic process.

关键词： Tetrahydropyrans Tetrahydrofurans Baldwin rules coumarins CYP450cyclase

Silica-bonded S-sulfonic acid a recyclable catalyst for the synthesis of coumarins

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Chinese Chemical Letters 2009年第12期20卷 1444-1448页

作者： Khodabakhsh Niknam Dariush Saberi Mojtaba Baghernejad Department of Chemistry Faculty of SciencesPersian Gulf University

Silica-bonded S-sulfonic acid （SBSSA） was prepared by the reaction of 3-mercaptopropylsilica （MPS） and chlorosulfonic acid in chloroform. This solid acid has been employed as a recyclable catalyst for the synthesi... 详细信息

关键词： Silica-bonded S-sulfonic acid coumarins Solvent-free Phenols -Keto-esters

Two New coumarins from Fraxinus chinensis Rexb.

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Journal of Integrative Plant Biology 2007年第2期49卷 218-221页

作者： Dong-Mei Zhang Li-Li Wang Jia Li Li-Hong Hu Shanghai Research Center for Modernization of Traditional Chinese Medicine Shanghai Institute of Materia Medica Shanghai Institute for Biological Sciences the Chinese Academy of Sciences Shanghai 201203 China National Center for Drug Screening Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences the Chinese Academy of Sciences Shanghai 201203 China School of Pharmacy East China University of Science and Technology Shanghai 200237 China

The ethanol extract of the stem bark of Fraxinus chinensis Roxb. showed good inhibitory bioactivity against VEGF receptor-1 kinase （IC50：13.8 μg/mL）. In order to find new and bioactive compounds, the chemical constituents of the stem bark of F. chinensis were investigated and two new coumarins, namely 6＇-O-sinapinoyl esculin （compound 1） and 6＇-O-vanillyl esculin （compound 2）, together with eleven known compounds （compounds 3-13） were isolated. The structures of the two new compounds were identified by their physicochemical properties and spectral analysis, particularly one- and two-dimensional nuclear magnetic resonance spectral methods. The known compound, oleuropein （compound 11）, exhibited moderate activity （IC50：（8.7 ± 1.3） μmol/L） to inhibit VEGF receptor- 1 kinase.

关键词： coumarins Fraxinus chinensis VEGF receptor-1 kinase.

Anti-Alzheimer's disease potential of coumarins from Angelica decursiva and Artemisia capillaris and structure-activity analysis

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Asian Pacific Journal of Tropical Medicine 2016年第2期9卷 101-108页

作者： Md.Yousof Ali Susoma Jannat Hyun Ah Jung Ran Joo Choi Anupom Roy Jae Sue Choi Department of Food and Life Science Pukyong National University Department of Food Science and Human Nutrition Chonbuk National University Angiogenesis& Chinese Medicine Laboratory Department of Pharmacology University of Cambridge

Objective: To use structure-activity analysis to study the anti-Alzheimer's disease(anti-AD) activity of natural coumarins isolated from Angelica decursiva and Artemisia capillaries, along with one purchased coumarin(daphnetin). Methods: Umbelliferone, umbelliferone 6-carboxylic acid, scopoletin, isoscopoletin, 7-methoxy coumarin, scoparone, scopolin, and esculetin have been previously isolated; however 2'-isopropyl psoralene was isolated from Angelica decursiva for the first time to evaluate their inhibitory effects against acetylcholinesterase(ACh E), butyrylcholinesterase(BCh E), and β-site amyloid precursor protein cleaving enzyme 1(BACE1) enzyme activity. We scrutinized the potentials of coumarins as cholinesterase and BACE1 inhibitors via enzyme kinetics and molecular docking simulation. Results: Among the test compounds, umbelliferone 6-carboxylic acid, esculetin and daphnetin exhibited potent inhibitory activity against ACh E, BCh E and BACE1. Both esculetin and daphnetin have a catechol group and exhibit significant anti-AD activity against ACh E and BCh E. In contrast, presence of a sugar moiety and methoxylation markedly reduced the anti-AD activity of the coumarins investigated in this study. With respect to BACE1 inhibition, umbelliferone 6-carboxylic acid, esculetin and daphnetin contained carboxyl or catechol groups, which significantly contributed to their antiAD activities. To further investigate these results, we generated a 3D structure of BACE1 using Autodock 4.2 and simulated binding of umbelliferone 6-carboxylic acid, esculetin and daphnetin. Docking simulations showed that different residues of BACE1 interacted with hydroxyl and carboxylic groups, and the binding energies of umbelliferone 6-carboxylic acid, esculetin and daphnetin were negative(-4.58,-6.25 and-6.37 kcal/mol respectively). Conclusions: Taken together, our results suggest that umbelliferone 6-carboxylic acid, esculetin and daphnetin have anti-AD effects by inhibiting ACh E, BCh

关键词： Umbelliferone 6-carboxylic acid Esculetin Daphnetin coumarins Cholinesterase BACE1

Oxalic acid catalyzed solvent-free one pot synthesis of coumarins

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Chinese Chemical Letters 2007年第11期18卷 1309-1312页

作者： Nagnnath D.Kokare Jaiprkash N.Sangshetti Devanand B.Shinde Department of Chemical Technology Dr.Babasaheb Ambedkar Marathwada University Aurangabad 431004 (MS)India Wockhardt Research CentreNew Drug DiscoveryAurangabad 431210 (MS)India Department of Chemical Technology Dr.Babasaheb Ambedkar Marathwada University Aurangabad 431004 (MS)India

Oxalic acid was found to be an efficient catalyst for Pechmann condensation, which includes the reaction between phenols and β-keto esters leading to formation of coumarin derivatives. The advantages of present methods are the use of cheap and easy available catalyst, solvent-free reaction conditions, better yields and shorter reaction time.

关键词： coumarins Oxalic acid Solvent-free reaction Pechmann condensation β-Keto esters Phenols