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Yin T, Zhao C, Yao C, Qian HD, Yuan Z, Peng H, Feng Y, Xu H. Copper-Catalyzed Remote Regio- and Enantioselective Yne-Allylic Substitution of Coumarins. Org Lett 2024. [PMID: 38984806 DOI: 10.1021/acs.orglett.4c02012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/11/2024]
Abstract
Chiral coumarins and their derivatives are prominent bioactive structural units present in a wide range of natural products and pharmaceutical candidates. Therefore, the development of straightforward and efficient methodologies for the synthesis of readily functionalized chiral coumarins is of significant interest. Herein we report an enantioselective copper-catalyzed yne-allylic substitution of coumarins, resulting in a highly regioselective synthesis of diverse new classes of chiral coumarin derivatives with high efficiency and excellent functional group tolerance. Subsequent versatile transformations further demonstrate the substantial synthetic potential of this strategy in the field of biochemical research.
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Affiliation(s)
- Tingrui Yin
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, State Key Laboratory of Green Pesticide, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan 430079, P. R. China
| | - Chunhui Zhao
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, State Key Laboratory of Green Pesticide, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan 430079, P. R. China
| | - Chaochao Yao
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, State Key Laboratory of Green Pesticide, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan 430079, P. R. China
| | - Hao-Dong Qian
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, State Key Laboratory of Green Pesticide, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan 430079, P. R. China
| | - Zisai Yuan
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, State Key Laboratory of Green Pesticide, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan 430079, P. R. China
| | - Hao Peng
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, State Key Laboratory of Green Pesticide, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan 430079, P. R. China
| | - Yadong Feng
- Engineering Research Center of Natural Cosmeceuticals College of Fujian Province, Department of Public Health and Medical Technology, Xiamen Medical College, 1999 Guankou Middle Road, Xiamen 361023, P. R. China
| | - Hao Xu
- Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction, State Key Laboratory of Green Pesticide, College of Chemistry, Central China Normal University, 152 Luoyu Road, Wuhan 430079, P. R. China
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2
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Singh S, Saini R, Singh RP. Enantioselective Distal Functionalization of 3-Cyano-4-methylcoumarins through Direct Vinylogous Conjugate Addition to Maleimides. J Org Chem 2022. [DOI: 10.1021/acs.joc.2c02142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sanjay Singh
- Department of Chemistry, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi 110016, India
| | - Ravi Saini
- Department of Chemistry, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi 110016, India
| | - Ravi P. Singh
- Department of Chemistry, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi 110016, India
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3
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Mitra S, Sarkar R, Chakrabarty A, Mukherjee S. Hydroxy-directed iridium-catalyzed enantioselective formal β-C(sp 2)-H allylic alkylation of α,β-unsaturated carbonyls. Chem Sci 2022; 13:12491-12497. [PMID: 36382287 PMCID: PMC9629034 DOI: 10.1039/d2sc03966d] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 10/12/2022] [Indexed: 02/12/2024] Open
Abstract
Hydroxy-directed iridium-catalyzed enantioselective formal β-C(sp2)-H allylic alkylation of kojic acid and structurally related α,β-unsaturated carbonyl compounds is developed. This reaction, catalyzed by an Ir(i)/(P,olefin) complex, utilizes the nucleophilic character of α-hydroxy α,β-unsaturated carbonyls, to introduce an allyl group at its β-position in a branched-selective manner in good to excellent yield with uniformly high enantioselectivity (up to >99.9 : 0.1 er). To the best of our knowledge, this report represents the first example of the use of kojic acid in a transition metal catalyzed highly enantioselective transformation.
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Affiliation(s)
- Sankash Mitra
- Department of Organic Chemistry, Indian Institute of Science Bangalore 560 012 India +91-80-2360-0529 +91-80-2293-2850
| | - Rahul Sarkar
- Department of Organic Chemistry, Indian Institute of Science Bangalore 560 012 India +91-80-2360-0529 +91-80-2293-2850
| | - Aditya Chakrabarty
- Department of Organic Chemistry, Indian Institute of Science Bangalore 560 012 India +91-80-2360-0529 +91-80-2293-2850
| | - Santanu Mukherjee
- Department of Organic Chemistry, Indian Institute of Science Bangalore 560 012 India +91-80-2360-0529 +91-80-2293-2850
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4
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Li H, Yin L. Research Progress of Copper-Catalyzed Direct Vinylogous Reactions. CHINESE J ORG CHEM 2022. [DOI: 10.6023/cjoc202201033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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5
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Tang S, Zhang P, Wang C, Shao Y, Sun J. Iridium-catalyzed regio- and enantioselective allylic esterification of secondary allylic alcohols with carboxylic acids. Chem Commun (Camb) 2021; 57:11080-11083. [PMID: 34617093 DOI: 10.1039/d1cc04861a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
We report herein an iridium-catalyzed asymmetric allylic esterification of racemic secondary allylic alcohols using free carboxylic acids as nucleophiles under mild conditions with broad functional group tolerance, exhibiting excellent regio- and enantioselectivity .
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Affiliation(s)
- Shengbiao Tang
- Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China.
| | - Peng Zhang
- Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China.
| | - Changkai Wang
- Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China.
| | - Ying Shao
- Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China.
| | - Jiangtao Sun
- Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China.
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6
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Palladium-catalyzed asymmetric allylic alkylation of 3-amino-2-oxindoles: Synthesis of 3-allyl-3-amino-2-oxindoles. Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2021.153385] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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7
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Oiarbide M, Palomo C. Extended Enolates: Versatile Intermediates for Asymmetric C-H Functionalization via Noncovalent Catalysis. Chemistry 2021; 27:10226-10246. [PMID: 33961323 PMCID: PMC8361983 DOI: 10.1002/chem.202100756] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Indexed: 12/22/2022]
Abstract
Catalyst-controlled functionalization of unmodified carbonyl compounds is a relevant operation in organic synthesis, especially when high levels of site- and stereoselectivity can be attained. This objective is now within reach for some subsets of enolizable substrates using various types of activation mechanisms. Recent contributions to this area include enantioselective transformations that proceed via transiently generated noncovalent di(tri)enolate-catalyst coordination species. While relatively easier to form than simple enolate congeners, di(tri)enolates are ambifunctional in nature and so control of the reaction regioselectivity becomes an issue. This Minireview discusses in some detail this and other problems, and how noncovalent activation approaches based on metallic and metal free catalysts have been developed to advance the field.
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Affiliation(s)
- Mikel Oiarbide
- Departamento de Química Orgánica IUniversidad del País Vasco UPV/EHUManuel Lardizabal 320018San SebastiánSpain
| | - Claudio Palomo
- Departamento de Química Orgánica IUniversidad del País Vasco UPV/EHUManuel Lardizabal 320018San SebastiánSpain
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8
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Mitra S, Mukherjee S. Iridium-Catalyzed Asymmetric Allylic Alkylation of Deconjugated Butyrolactams. Org Lett 2021; 23:3021-3026. [PMID: 33821654 DOI: 10.1021/acs.orglett.1c00697] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Compared with the ever-growing list of nonprochiral nucleophiles in Ir-catalyzed asymmetric allylic substitution reactions, prochiral nucleophiles are less studied. We present a new prochiral nucleophile, namely, deconjugated butyrolactam, for Ir-catalyzed asymmetric allylic alkylation (AAA). This reaction provides access to α-allyl deconjugated butyrolactams with a moderate to good dr and an excellent er. This is the first AAA reaction of deconjugated butyrolactams. Allyl transposition through Cope rearrangement appears to proceed stereospecifically to form γ-allyl conjugated butyrolactams.
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Affiliation(s)
- Sankash Mitra
- Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India
| | - Santanu Mukherjee
- Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India
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9
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Sarkar R, Mukherjee S. Iridium-catalyzed enantioselective olefinic C(sp 2)-H allylic alkylation. Chem Sci 2021; 12:3070-3075. [PMID: 34164076 PMCID: PMC8179414 DOI: 10.1039/d0sc06208a] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 02/11/2021] [Accepted: 01/14/2021] [Indexed: 12/14/2022] Open
Abstract
The first iridium-catalyzed enantioselective olefinic C(sp2)-H allylic alkylation is developed in cooperation with Lewis base catalysis. This reaction, catalyzed by cinchonidine and an in situ generated cyclometalated Ir(i)/phosphoramidite complex, makes use of the latent enolate character of an α,β-unsaturated carbonyl compound, namely coumalate ester, to introduce an allyl group at its α-position in a branched-selective manner in moderate to good yield with good to excellent enantioselectivities (up to 98 : 2 er).
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Affiliation(s)
- Rahul Sarkar
- Department of Organic Chemistry, Indian Institute of Science Bangalore 560 012 India +91-80-2360-0529 +91-80-2293-2850
| | - Santanu Mukherjee
- Department of Organic Chemistry, Indian Institute of Science Bangalore 560 012 India +91-80-2360-0529 +91-80-2293-2850
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10
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Jaiswal MK, Kumar R, Singh S, Jain S, Vanka K, Singh RP. The Vinylogous Michael Addition of 3‐Alkylidene‐2‐oxindoles to β,γ‐Unsaturated α‐Keto Esters by Bifunctional Cinchona Alkaloids. European J Org Chem 2020. [DOI: 10.1002/ejoc.202000835] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Manish K. Jaiswal
- Department of Chemistry Indian Institute of Technology‐Delhi Hauz Khas 110016 New Delhi India
| | - Rajesh Kumar
- Department of Chemistry Indian Institute of Technology‐Delhi Hauz Khas 110016 New Delhi India
| | - Sanjay Singh
- Department of Chemistry Indian Institute of Technology‐Delhi Hauz Khas 110016 New Delhi India
| | - Shailija Jain
- Physical and Materials Chemistry Division National Chemical Laboratory Dr. Homi Bhabha Road 411008 Pune India
| | - Kumar Vanka
- Physical and Materials Chemistry Division National Chemical Laboratory Dr. Homi Bhabha Road 411008 Pune India
| | - Ravi P. Singh
- Department of Chemistry Indian Institute of Technology‐Delhi Hauz Khas 110016 New Delhi India
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11
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Curti C, Battistini L, Sartori A, Zanardi F. New Developments of the Principle of Vinylogy as Applied to π-Extended Enolate-Type Donor Systems. Chem Rev 2020; 120:2448-2612. [PMID: 32040305 PMCID: PMC7993750 DOI: 10.1021/acs.chemrev.9b00481] [Citation(s) in RCA: 99] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Indexed: 12/19/2022]
Abstract
The principle of vinylogy states that the electronic effects of a functional group in a molecule are possibly transmitted to a distal position through interposed conjugated multiple bonds. As an emblematic case, the nucleophilic character of a π-extended enolate-type chain system may be relayed from the legitimate α-site to the vinylogous γ, ε, ..., ω remote carbon sites along the chain, provided that suitable HOMO-raising strategies are adopted to transform the unsaturated pronucleophilic precursors into the reactive polyenolate species. On the other hand, when "unnatural" carbonyl ipso-sites are activated as nucleophiles (umpolung), vinylogation extends the nucleophilic character to "unnatural" β, δ, ... remote sites. Merging the principle of vinylogy with activation modalities and concepts such as iminium ion/enamine organocatalysis, NHC-organocatalysis, cooperative organo/metal catalysis, bifunctional organocatalysis, dicyanoalkylidene activation, and organocascade reactions represents an impressive step forward for all vinylogous transformations. This review article celebrates this evolutionary progress, by collecting, comparing, and critically describing the achievements made over the nine year period 2010-2018, in the generation of vinylogous enolate-type donor substrates and their use in chemical synthesis.
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Affiliation(s)
| | | | | | - Franca Zanardi
- Dipartimento di Scienze degli
Alimenti e del Farmaco, Università
di Parma, Parco Area delle Scienze 27A, 43124 Parma, Italy
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12
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Wang J, Zhang S, Ding W, Wang C, Chen J, Cao W, Wu X. Amide‐phosphonium Salt Catalyzed Enantioselective Vinylogous Mannich Addition of Coumarins to Isatin Imines. ChemCatChem 2019. [DOI: 10.1002/cctc.201901677] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Jing Wang
- Center for Supramolecular Chemistry and Catalysis and Department of Chemistry College of SciencesShanghai University 99 Shangda Lu Shanghai 200444 P. R. China
| | - Shuo Zhang
- Center for Supramolecular Chemistry and Catalysis and Department of Chemistry College of SciencesShanghai University 99 Shangda Lu Shanghai 200444 P. R. China
| | - Weizhong Ding
- Center for Supramolecular Chemistry and Catalysis and Department of Chemistry College of SciencesShanghai University 99 Shangda Lu Shanghai 200444 P. R. China
| | - Chenghan Wang
- Center for Supramolecular Chemistry and Catalysis and Department of Chemistry College of SciencesShanghai University 99 Shangda Lu Shanghai 200444 P. R. China
| | - Jie Chen
- Center for Supramolecular Chemistry and Catalysis and Department of Chemistry College of SciencesShanghai University 99 Shangda Lu Shanghai 200444 P. R. China
| | - Weiguo Cao
- Center for Supramolecular Chemistry and Catalysis and Department of Chemistry College of SciencesShanghai University 99 Shangda Lu Shanghai 200444 P. R. China
| | - Xiaoyu Wu
- Center for Supramolecular Chemistry and Catalysis and Department of Chemistry College of SciencesShanghai University 99 Shangda Lu Shanghai 200444 P. R. China
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13
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Xiao BX, Shi CH, Liang SY, Jiang B, Du W, Chen YC. Remote Friedel–Crafts Reaction with α-Heteroaryl-Substituted Cyclic Ketones via HOMO Activation of Lewis Bases. Org Lett 2019; 21:7554-7557. [PMID: 31469571 DOI: 10.1021/acs.orglett.9b02827] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Ben-Xian Xiao
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Chong-Hui Shi
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Shu-Yuan Liang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Bo Jiang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Wei Du
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Ying-Chun Chen
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
- College of Pharmacy, Third Military Medical University, Shapingba, Chongqing 400038, China
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14
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Sarkar R, Mukherjee S. Enantioselective Direct Vinylogous Allylic Alkylation of 4-Methylquinolones under Iridium Catalysis. Org Lett 2019; 21:5315-5320. [PMID: 31247781 DOI: 10.1021/acs.orglett.9b01934] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The first enantioselective vinylogous allylic alkylation of 4-methylquinolones has been developed. This iridium-catalyzed reaction introduces an allyl group at the γ-position of 4-methyl-2-quinolones with exclusive branched selectivity and an excellent level of enantioselectivity. This in turn allows for the enantioselective synthesis of γ-allylquinolines and related nitrogenous heterocycles. This is the first application of 4-methylquinolones in an enantioselective transformation.
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Affiliation(s)
- Rahul Sarkar
- Department of Organic Chemistry , Indian Institute of Science , Bangalore 560012 , India
| | - Santanu Mukherjee
- Department of Organic Chemistry , Indian Institute of Science , Bangalore 560012 , India
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15
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Dai Y, Tian B, Chen H, Zhang Q. Palladium-Catalyzed Stereospecific C-Glycosylation of Glycals with Vinylogous Acceptors. ACS Catal 2019. [DOI: 10.1021/acscatal.9b00336] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Yuanwei Dai
- Department of Chemistry, University at Albany, State University of New York, Albany, New York 12222, United States
| | - Baotong Tian
- Department of Chemistry, University at Albany, State University of New York, Albany, New York 12222, United States
| | - Huan Chen
- Department of Chemistry, University at Albany, State University of New York, Albany, New York 12222, United States
| | - Qiang Zhang
- Department of Chemistry, University at Albany, State University of New York, Albany, New York 12222, United States
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Cheng Q, Tu HF, Zheng C, Qu JP, Helmchen G, You SL. Iridium-Catalyzed Asymmetric Allylic Substitution Reactions. Chem Rev 2018; 119:1855-1969. [PMID: 30582688 DOI: 10.1021/acs.chemrev.8b00506] [Citation(s) in RCA: 442] [Impact Index Per Article: 73.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In this review, we summarize the origin and advancements of iridium-catalyzed asymmetric allylic substitution reactions during the past two decades. Since the first report in 1997, Ir-catalyzed asymmetric allylic substitution reactions have attracted intense attention due to their exceptionally high regio- and enantioselectivities. Ir-catalyzed asymmetric allylic substitution reactions have been significantly developed in recent years in many respects, including ligand development, mechanistic understanding, substrate scope, and application in the synthesis of complex functional molecules. In this review, an explicit outline of ligands, mechanism, scope of nucleophiles, and applications is presented.
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Affiliation(s)
- Qiang Cheng
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Lu , Shanghai 200032 , China
| | - Hang-Fei Tu
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Lu , Shanghai 200032 , China
| | - Chao Zheng
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Lu , Shanghai 200032 , China
| | - Jian-Ping Qu
- Institute of Advanced Synthesis, School of Chemistry and Molecular Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials , Nanjing Tech University , Nanjing 211816 , China
| | - Günter Helmchen
- Organisch-Chemisches Institut der Ruprecht-Karls , Universität Heidelberg , Im Neuenheimer Feld 270 , D-69120 Heidelberg , Germany
| | - Shu-Li You
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry , University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Lu , Shanghai 200032 , China
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