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

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 bioactivities.However,the biosynthetic mechanisms for their core structures remain poorly understood.Here 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 plants.These included three distinct P.praeruptorum 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 scaffolds.Biochemical analyses of cyclases indicated that acid/base-assisted epoxide ring opening contributed to the enzyme-catalyzed tetrahydropyran and tetrahydrofuran ring refactoring.The possible acid/base-assisted catalytic mechanisms of the identified cyclases were theoretically investigated and assessed using site-specific mutagenesis.We identified two possible acidic amino acids Glu303 in PpDC and Asp301 in PpOC as vital in the catalytic process.This 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

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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

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Anticancer carbazole alkaloids and coumarins from Clausena plants： A review

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Chinese Journal of Natural Medicines 2017年第12期15卷 881-888页

作者： HUANG Li FENG Zhe-Ling WANG Yi-Tao LIN Li-Gen State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical Sciences University of MacaoMacao 999078 China

Pharmaceutical research has focused on the discovery and development of anticancer drugs. Clinical application of chemotherapy drugs is limited due to their severe side effects. In this regard, new naturally occurring anticancer drugs have gained increasing attention because of their potential effectiveness and safety. Fruits and vegetables are promising sources of anticancer remedy. Clausena(family Rutaceae) is a genus of flowering plants and includes several kinds of edible fruits and vegetables. Phytochemical and pharmacological studies show that carbazole alkaloids and coumarins from Clausena plants exhibit anticancer activity. This review summarizes research progresses made in the anticancer properties of plants belonging to Clausena; in particular, compounds with direct cytotoxicity, cell cycle arrest, apoptosis induction, and immune potentiation effects are discussed. This review reveals the potential use of plants from Clausena in preventing and treating cancer and provides a basis for development of relevant therapeutic agents.

关键词： Clausena Anticancer Carbazole alkaloids coumarins

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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 E and BACE1, which might be useful against AD.

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

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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 integerrimum.Their 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 data.Compounds 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

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Melamine-formaldehyde resin supported H^+:A mild and inexpensive reagent for synthesis of coumarins under mild conditions

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Chinese Chemical Letters 2011年第11期22卷 1313-1316页

作者： Ramin Rezaei Leila Dorosty Maryam Rajabzadeh Reza Khalifeh Department of Chemistry Firoozabad Branch Islamic Azad UniversityP.O.Box 74715-117 FiroozabadIran Department of Chemistry Faculty of Basic Sciences ShirazUniversity of TechnologyShiraz71555-313Iran

Melamine-formaldehyde resin supported H~＋ is used as an efficient catalyst in the Pechmann condensation reaction of phenols withβ-ketoesters,in solvent-free media leading to the formation of coumarin derivatives usi... 详细信息

关键词： coumarins Phenols β-Ketoesters Melamine-formaldehyde resin Pechmann condensation Solvent-free

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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.

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A Semi-Vectorial Morphological Segmentation Multi-Component Images of coumarins on Thin Layer Combined with Laser for Better Separation

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Open Journal of Applied Sciences 2022年第6期12卷 1054-1068页

作者： Theodore Guié Toa Bi Marcelin Sandjé Régnima G. Oscar Sie Ouattara Alain Clement UFR Science and Technology University of Man Man Ivory Coast Laboratory of Communication and Information Science and Technology (LSTCI) National Polytechnic Institute Houphou&#235 t Boigny Yamoussoukro C&ocirc te d’Ivoire University Institute of Technology of Angers (IUT) Angers France

In this work, we propose an approach for the separation of coumarins from thin-layer morphological segmentation based on the acquisition of multicomponent images integrating different types of coumarins. The first step is to make a segmentation by region, by thresholding, by contour, etc. of each component of the digital image. Then, we proceeded to the calculations of parameters of the regions such as the color standard deviation, the color entropy, the average color of the pixels, the eccentricity from an algorithm on the matlab software. The mean color values atR = 91.20 in red, atB = 213.21 in blue showed the presence of samidin in the extract. The color entropy values HG = 5.25 in green and HB = 4.04 in blue also show the presence of visnadine in the leaves of Desmodium adscendens. These values are used to consolidate the database of separation and discrimination of the types of coumarins. The relevance of our coumarin separation or coumarin recognition method has been highlighted compared to other methods, such as the one based on the calculation of frontal ratios which cannot discriminate between two coumarins having the same frontal ratio. The robustness of our method is proven with respect to the separation and identification of some coumarins, in particular samidin and anglicine.

关键词： Identification Thin Layer Secondary Metabolites coumarins Image Acquisition Segmentation Standard Deviation Entropy Average Color Algorithm Matlab

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Silica triflate as an efficient reagent for the solvent-free synthesis of coumarins

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Chinese Chemical Letters 2007年第8期18卷 909-911页

作者： Farhad Shirini Katayoun Marjani Hossein Taherpour Nahzomi Mohammad Ali Zolfigol Department of Chemistry College of ScienceGuilan UniversityRasht 41335Iran Faculty of Chemistry Teacher Training UniversityTehran 15614Iran Department of Chemistry College of ScienceBu-Ali Sina UniversityHamadan 65174Iran

Silica triflate, as a new silica-based reagent, can be used for the efficient synthesis of 4-substituted coumarins via a Pechmann reaction under solvent-free reaction conditions. All reactions were performed at 80 ℃ ... 详细信息

关键词： Silica triflate coumarins Pechmann reaction Solvent-free reaction conditions Phenols

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Glycoside-specific metabolomics combined with precursor isotopic labeling for characterizing plant glycosyltransferases

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Molecular Plant 2022年第10期15卷 1517-1532页

作者： Jie Wu Wentao Zhu Xiaotong Shan Jinyue Liu Lingling Zhao Qiao Zhao Shenzhen Key Laboratory of Synthetic Genomics Guangdong Provincial Key Laboratory of Synthetic GenomicsCAS Key Laboratory of Quantitative Engineering BiologyShenzhen Institute of Synthetic BiologyShenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Innovation Center of Pesticide Research Department of Applied ChemistryCollege of ScienceChina Agricultural UniversityBeijing 100193China Center for Plant Biology School of Life SciencesTsinghua UniversityBeijing 100084China

Glycosylation by uridine diphosphate-dependent glycosyltransferases(UGTs)in plants contributes to the complexity and diversity of secondary metabolites.UGTs are generally promiscuous in their use of acceptors,making it challenging to reveal the function of UGTs in vivo.Here,we described an approach that combined glycoside-specific metabolomics and precursor isotopic labeling analysis to characterize UGTs in Arabidopsis.We revisited the UGT72E cluster,which has been reported to catalyze the glycosylation of monolignols.Glycoside-specific metabolomics analysis reduced the number of differentially accumulated metabolites in the ugt72e1e2e3 mutant by at least 90%compared with that from traditional untargeted metabolomics analysis.In addition to the two previously reported monolignol glycosides,a total of 62 glycosides showed reduced accumulation in the ugt72e1e2e3 mutant,22 of which were phenylalanine-derived glycosides,including 5-OH coniferyl alcohol-derived and lignan-derived glycosides,as confirmed by isotopic tracing of[^(13)C_(6)]-phenylalanine precursor.Our method revealed that UGT72Es could use coumarins as substrates,and genetic evidence showed that UGT72Es endowed plants with enhanced tolerance to low iron availability under alkaline conditions.Using the newly developed method,the function of UGT78D2 was also evaluated.These case studies suggest that this method can substantially contribute to the characterization of UGTs and efficiently investigate glycosylation processes,the complexity of which have been highly underestimated.

关键词： glycosyltransferases glycosides-specific metabolomics precursor isotopic labeling glucoside Arabidopsis thaliana phenylpropanoid coumarins

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