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Chemical Research in Chinese Universities 2007年第1期23卷 35-43页

作者： CHENG Xiao-hong HOEGER Sigurd Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of Education School of Chemistry and Material Engineering Yunnan University Kunming 650091 P. R. China University Karlsruhe Institute for Technic Chemistry and Polymer Chemistry Engesserstr. 18 76131 Karlsruhe Germany

On the basis of the C-C coupling reactions of dibenzo [ fg, op ] naphthacene bistriflate, which was obtained by the condensation of phenylacetates with 4-aryl-2,6-bis（2-bromo-4-methoxy-phenyl） pyrylium salts followed by palladium-catalyzed dehydrohalogenation, three shape-persistent macrocycles with dibenzonaphthacene corner pieces, a nanometer interior void, and intraanular oligoalkyl side groups were synthesized by the oxidative cyclization of the corresponding bisacetylenes under high-dilution conditions. Their thermotropic liquid crystalline properties were investigated by using polarizing microscopy and differential scanning calorimetry. All the three compounds showed nematic mesophases and belonged to discotic liquid crystals with inverted topology.

关键词： Dibenzo [ fg, op ] naphthacene macrocycles Liquid crystal C-C coupling

Synthesis of Donor-Acceptorπ-Conjugated macrocycles by Post-Functionalization

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Chinese Journal of Chemistry 2021年第10期39卷 2705-2710页

作者： Junting Wang Qingyun Wan Junzhi Liu Department of Chemistry and State Key Laboratory of Synthetic Chemistry The University of Hong KongPokfulam RoadHong KongChina

Main observation and conclusion In this paper,two novel donor-acceptor(D-A)macrocyclic compounds 5 and 7 were successfully synthesized by post-functionalization of a planar dimer macrocycle(1)and a highly twisted trimer macrocycle(2),respectively,via controllable oxidation of methoxy groups and condensation between diketones and phenylenediamine in *** with unembellished 9,10-dimethoxyphenanthrene,the resultant dibenzo[a,c]phenazine motif is electron-deficient rather than electron-rich,yielding two D-Aπ-conjugated macrocycles with more contractive energy *** functional theory(DFT)calculations further support the unequivocal evidence of the D-A properties of macrocycles 5 and *** difference of their photophysical properties was investigated by the aid of ultraviolet-visible absorption and fluorescence ***,the stacking patterns of 7 and its contrastπ-conjugated macrocycle trimer(2)were compared via the analysis of X-ray single crystal,in which the electron-deficient dibenzo[a,c]phenazine unit provides extra interaction sites,resulting in orderly arrangement of 7 in the solid state.

关键词： macrocycles Post-functionalization Donor-acceptor systems Oxidation Stacking interactions

Novel macrocycles Bearing Dithienylethene Units and Urea Functional Groups Synthesis, Structure and Photochromic Property

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Chinese Journal of Chemistry 2013年第5期31卷 627-634页

作者： Tangxin Xiao Shaolu Li Xiaoning Zhang Chen Lin LeyongWang Key Laboratory of Mesoscopic Chemistry of Ministry of Education Center for Multimolecular Chemistry School of Chemistry and Chemical Engineering Nanjing University Nanjing Jiangsu 210093 China

Two novel photochromic macrocycles 1 and 2 bearing dithienylethene units and urea building blocks have been synthesized, and their photochromic properties are described. Macrocycle 2 shows good photochromic properties, while the relatively smaller size of macrocycle 8h exhibits photochemically inactive properties due to the unfa- vourable ring conformational constraint. Moreover, the crystal structures of the urea-protected precursor macrocyles 3a, 3h, and 8b are presented.

关键词： photochromism macrocycles dithienylethene urea derivatives supramolecular chemistry

Synthesis of Novel C_2-Symmetric Chiral Polyamide macrocycles Containing Pyridyl Side-arm

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Chinese Chemical Letters 2002年第11期13卷 1037-1038页

作者： XiaoCHEN DaMingDU 等 ThekeyLaboratoryofBioorganicChemistryandMolecularEngineeringofMinistryofEduationCollegeofChemistry＆MolecularEngineering PekingUniversityBeijing100871 ThekeyLaboratoryofBioorganicChemistryandMolecular

Three novel C2-symmetric macrocycles containing pyridyl units have been prepared by the cyclic condensation of chiral diamide intermediates with 2,6-pyridinedicarbonyl dichloride in highly diluted solution at room tem... 详细信息

关键词： Synthesis macrocycles chiral pyridine.

Shape linear peptides into rigid rings: a sp^3 C–H arylation approach to cyclophane-braced peptide macrocycles

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Science China Chemistry 2018年第12期61卷 1477-1478页

作者： Yuankun Dao Suwei Dong State Key Laboratory of Natural and Biomimetic Drugs and Department of Chemical Biology School of Pharmaceutical SciencesPeking University

Peptide-based therapeutics have attracted increasing attention due to their unique properties in comparison to small molecule drugs and recombinant biologics [1].With moderate size and suitable surface area,peptides possess enormous potential in drug discovery for their promising capabilities of intercepting protein-protein interactions (PPIs),which is extremely difficult to be accomplished using small molecule compounds [2].

关键词： Shape linear peptides rigid rings peptide macrocycles

Photophysical Properties of the Asymmetric Pentaazadentate Porphyrin-like macrocycles

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Science China Chemistry 1994年第4期37卷 402-409页

作者：董世明王夺元 Institute of Photographic Chemistry Academia Sinica Beijing 100101 PRC

The linear correlations of Hammett constants with the 0-0 transition energies, and the ratios of the oscillator strength are used to probe the conjugation interactions between π-electron of macrocy-cles and metal ion of complexes with the substituents on m-position of benzene ring for the asymmetric pen-taazadentate porphyrin-like compounds. The absorption and fluorescence spectra appear on λmax> 750 nm and 769 nm near-IR regions respectively. The quantum yields and lifetimes of fluorescence are about 10-2and less than 1 ns respectively. The T1--Tn transient absorption spectra appear on 487-496 nm and thequantum yields for generating singlet oxygen are as high as 0. 86.

关键词： asymmetric pentaazadentate macrocycles Hammett linear relationships photophysical properties singlet oxygen T1-Tn absorption spectra.

Cucurbit[8]uril-regulated face-to-face dimerization assembly enhanced photosensitization and photocatalysis

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Science China Chemistry 2024年第5期67卷 1605-1612页

作者： Haigen Nie Die Hu Zhiyao Zeng Yan Fan Yaxin Zhai Xin-Long Ni Key Laboratory of Chemical Biology and Traditional Chinese Medicine Ministry of Educational of ChinaKey Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan ProvinceCollege of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha 410081China Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of PhysicsHunan Normal UniversityChangsha 410081China

In water, N,N′-diarylpyridinium thiazolo[5,4-d]thiazole guests(G1–G3) were encapsulated by cucurbit[8]uril(Q[8]) to construct Q[8]_(3)/G_(2) complexes, in which the encapsulated G molecules exist as an exact face-to-face dimer. These complexation behaviors have been indicated by proton nuclear magnetic resonance(~1H NMR) spectroscopy and isothermal titration calorimetry(ITC),and have been confirmed by X-ray single crystal structural analysis of Q[8]_(3)/G2_(2). While free guests G1–G3 have no ability to sensitize singlet oxygen, they all become effective singlet oxygen sensitizers when complexed with Q[8]. By irradiation of white light, Q[8]_(3)/G_(2) complexes induced selective oxidation of aryl sulfide to aryl sulfoxide in good yields and selective oxidation of dimethyl sulfide(DMS) to dimethyl sulfoxide(DMSO) in excellent yields without over-oxidation to dimethyl sulfone(DMSO_(2))even for elongated irradiation. High-yield photo-oxidation of DMS to DMSO_(2) was only achieved by irradiation of blue light in the presence of Q[8]_(3)/G1_(2), which was also effective in photobleaching of Rhodamine B in water. The higher photo-oxidation power of Q[8]_(3)/G1_(2) has been ascribed to an additional generation of reactive oxygen species besides singlet oxygen.

关键词： host-guest interaction dimerization macrocycles photosensitization

Molecular recognition of cyclophanes in water

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Chinese Chemical Letters 2024年第5期35卷 32-44页

作者： Fang-Yuan Chen Wen-Chao Geng Kang Cai Dong-Sheng Guo College of Chemistry State Key Laboratory of Elemento-Organic ChemistryKey Laboratory of Functional Polymer Materials(Ministry of Education)Frontiers Science Center for New Organic MatterCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)Nankai UniversityTianjin 300071China College of Chemistry Nankai UniversityTianjin 300071China

Molecular recognition in water,the biological solvent,always receives significant research focus in supramolecular *** mechanisms of molecular recognition in water is key to comprehending biological processes at the molecular *** the past five decades,supramolecular chemists have developed a vast array of synthetic receptors with highly diverse structures and recognition *** them,cyclophanes represent an important family of macrocyclic receptors that have been extensively *** aromatic moieties in cyclophanes not only facilitate chemical modifications to impart water solubility but also enable forming hydrophobic cavities for guest inclusion in aqueous *** by Koga et al.,who reported the first inclusion complex of cyclophanes in water and solid state,numerous water-soluble cyclophanes,including derivatives of blue box,calixarenes,resorcinarenes,pillararenes,octopusarenes,biphenarenes,coronarenes,and naphthotubes,etc.,have been synthesized and subjected to investigation of the recognition capabilities in aqueous *** review provides an overview of cyclophane receptors designed to bind organic guests in *** categorize them into two classes based on the modifications made to their hydrophobic cavities:those with“exo-functionalized hydrophobic cavities”and those with“endo-functionalized hydrophobic cavities”.We introduce their distinctive features and discuss strategies to enhance recognition affinity and *** review aims to inspire the development of novel synthetic receptors with intriguing properties and foster practical applications of cyclophanes.

关键词： Biomimetic receptor Cyclophane Molecular recognition Hydrophobic effect High-affinity macrocycles

Zwitterionic ring-opening polymerization of macrocyclic ethyleneoxy-substituted carbonate:Access to cyclic PEG-like polycarbonate

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Chinese Chemical Letters 2024年第3期35卷 282-286页

作者： Jin Huang Jinwen Li Rui Yan Yuanyuan Qu Fengzhen Guo Lei Shen Can-liang Ma Jie Sun Zhenjiang Li Kai Guo State Key Laboratory of Materials-Oriented Chemical Engineering College of Biotechnology and Pharmaceutical EngineeringNanjing Tech UniversityNanjing 211816China Institute of Nanjing Advanced Biomaterials&Processing Equipment Lishui Economic Development ZoneNanjing 211299China

The innovation in polymer design to rival conventional polyethylene glycol(PEG)is an important approach to achieving a more sustainable ***,cyclic PEG-like polycarbonates having high molecular weight(4.4–49.5 kg/mol)were enabled through zwitterionic ring-opening polymerization(ZROP)of macrocyclic carbonates(MCs)mediated by N-heterocyclic carbene(NHC).The thermodynamic behavior of polymerization depends on the ring size of *** this process,the ZROP of 11-membered MC was driven by the change of enthalpy(ΔH_(p))which differed from the ZROP of 14-membered MC driven by the entropic change(ΔS_(p)).Cyclic polycarbonates depicted improved thermostability(T_(d5%)≥204℃)and higher glass transition temperatures(T_(g)>–40℃)in comparison to their linear analogues(T_(d5%)≤185℃,T_(g)~–50℃).In addition,the mechanism of ZROP of MC was addressed through computational study.A distinct mechanism of polymerization distinguishable from the well-known NHC-mediated ZROP of cyclic esters was revealed,where the zwitterion from nucleophilic addition to MC,*** intermediate,cannot be ring-opened probably due to the delocalization of negative charge on the carbonate group,but serves as an active center for the *** comparison to PEG,the attained polymer demonstrated comparable hydrophilic and biocompatible properties,as revealed by the results of contact angle and in vitro cytotoxicity studies,suggesting that cyclic polycarbonate hold the promise as the alternative of PEG.

关键词： Zwitterionic ring-opening polymerization Cyclic polycarbonate macrocycles Tetrahedral intermediate NHC carbene

Synthesis of macrocycles Based on Glycoluril Scaffold with Various Space Linkers

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Synthesis of Macrocycles Based on Glycoluril Scaffold with V...