Chirality,ubiquitous in living matter,plays vital roles in a series of physiological processes.The clarification of the multiple functions of chirality in bioapplications may provide innovative methodologies for engin...Chirality,ubiquitous in living matter,plays vital roles in a series of physiological processes.The clarification of the multiple functions of chirality in bioapplications may provide innovative methodologies for engineering anti-tumor agents.Nevertheless,the related research has been rarely explored.In this study,the chiral supramolecular l/d-cysteine(Cys)-Zn^(2+)-indocyanine green(ICG)nanoparticles were constructed through the coordination interaction between l/d-Cys and Zn^(2+),followed by the encapsulation of ICG.Experimental findings revealed that the d-Cys-Zn^(2+)-ICG exhibited 17.31 times higher binding affinity toward phospholipid-composed liposomes compared to l-Cys-Zn^(2+)-ICG.Furthermore,driven by chiralityspecific interaction,a 2.07 folds greater cellular internalization of d-Cys-Zn^(2+)-ICG than l-Cys-Zn^(2+)-ICG was demonstrated.Additionally,the triple-level chirality-dependent photothermal,photodynamic and Zn^(2+)releasing anti-tumor effects of l/d Cys-Zn^(2+)-ICG in vitro were verified.As a result,the d-formed nanoparticles achieved 1.93 times higher anti-tumor efficiency than the l-formed ones.The triple-level chirality-mediated anti-tumor effect highlighted in this study underscores the enormous potential of chirality in biomedicine and holds substantial significance in improving cancer therapeutic efficacy.展开更多
To get large dissymmetric factor(g_(lum))of organic circularly polarized luminescence(CPL)materials is still a great challenge.Although helical chirality and planar chirality are usual efficient access to enhancement ...To get large dissymmetric factor(g_(lum))of organic circularly polarized luminescence(CPL)materials is still a great challenge.Although helical chirality and planar chirality are usual efficient access to enhancement of CPL,they are not combined together to boost CPL.Here,a new tetraphenylethylene(TPE)tetracycle acid helicate bearing both helical chirality and planar chirality was designed and synthesized.Uniquely,synergy of the helical chirality and planar chirality was used to boost CPL signals both in solution and in helical self-assemblies.In the presence of octadecylamine,the TPE helicate could form helical nanofibers that emitted strong CPL signals with an absolute g_(lum)value up to 0.237.Exceptionally,followed by addition of para-phenylenediamine,the g_(lum)value was successively increased to 0.387 due to formation of bigger helical nanofibers.Compared with that of TPE helicate itself,the CPL signal of the self-assemblies was not only magnified by 104-fold but also inversed,which was very rare result for CPL-active materials.Surprisingly,the interaction of TPE helicate with xylylenediamine even gave a gel,which was transformed into suspension by shaking.Unexpectedly,the suspension showed 40-fold stronger CPL signals than the gel with signal direction inversion each other.Using synergy of the helical chirality and planar chirality to significantly boost CPL intensity provides a new strategy in preparation of organic CPL materials having very large g_(lum)value.展开更多
In light of the double helix structure hypothesis for photon,we attempt to elucidate the generation mechanism underlying TF(Torsion Field)from both wave and particle perspectives and the enigma surrounding chiral life...In light of the double helix structure hypothesis for photon,we attempt to elucidate the generation mechanism underlying TF(Torsion Field)from both wave and particle perspectives and the enigma surrounding chiral life on Earth by proposing a neutrino-propagation model for TF,which will serve as a crucial key in unraveling the enigma of life’s origins and is promising to trigger a paradigm transformation in future medical and healthcare technologies.展开更多
The scale mismatch between nanoscale biomolecules and sub-wavelength light hinders circular dichroism(CD)spectroscopy for chiral small molecule sensing.In this study,we propose a high quality-factor(Q-factor)optical c...The scale mismatch between nanoscale biomolecules and sub-wavelength light hinders circular dichroism(CD)spectroscopy for chiral small molecule sensing.In this study,we propose a high quality-factor(Q-factor)optical cavity that offers a breakthrough solution to the intrinsic trade-off between optical chirality density and mode loss.A spin-preserving chiral metasurface utilizes bound states in the continuum(BIC)-guided mode resonance(GMR)degenerate modes to achieve a high Q-factor,while ensuring the preservation of chirality purity for circularly polarized light propagating within the cavity via spin-locking mechanism.Experimental results demonstrate that the BIC-GMR degenerate state enables near-perfect transmission CD up to 0.99,without requiring symmetry breaking.Full-wave simulations further predict that this synergistically enhanced system can achieve a Q-factor as high as 10037 and generate a localized field in the molecular interaction region with an optical chirality density enhancement of up to 400-fold,leading to 5025-fold amplification of the CD signal.This study establishes a foundation for detecting low-concentration chiral molecules,reveals high-Q enhancement,and advances chiral toward single-molecule sensitivity,opening new research avenues in chiral biosensing.展开更多
Phylogenetic relations of twining chirality of Dioscorea sp.in China were analyzed based on the genes matK,rbcL and trnL;phylogenetic character of higher-level phylogeny of twining plants was analyzed at a high taxon ...Phylogenetic relations of twining chirality of Dioscorea sp.in China were analyzed based on the genes matK,rbcL and trnL;phylogenetic character of higher-level phylogeny of twining plants was analyzed at a high taxon level based on matK gene.A significant phylogenetic framework of chirality was found:(i)based on matK analysis,right-handed Dioscorea species in China congregate completely to form a monophyly;(ii)rbcL and trnL data sets also supported Chinese right-handed Dioscorea a monophyly,although with ex...展开更多
Chirality,commonly found in organisms,biomolecules and nature such as L-amino acids and D-sugars,has been extensively studied in chemistry and biomedical science.Hence,the demand for simple and efficient construction ...Chirality,commonly found in organisms,biomolecules and nature such as L-amino acids and D-sugars,has been extensively studied in chemistry and biomedical science.Hence,the demand for simple and efficient construction of chiral structures,especially chiral polymers,has been rapidly growing due to their potential applications in chemosensors,asymmetric catalysis and biological materials.However,most chiral polymers reported are prepared directly from chiral monomers/chiral catalysts,the corresponding strategies usually involve tedious and expensive design and synthesis.Fortunately,chirality induction strategies(such as circularly polarized light,chiral solvation and chiral gelation etc.)have been known to be highly versatile and efficient in producing chirality from achiral polymers.In this feature article,the current research on chirality induction,transfer and application in achiral polymer systems is summarized.Furthermore,this article discusses some basic concepts,seminal studies,recent advances,the structural design principles,as well as perspectives in the construction and applications of chiral polymers derived from achiral monomers,with the hope to attract more interest from researchers and further advance the development of chiral chemistry.展开更多
The crystal structure of tetrakis[(pyrrol-1-yl)methyl]methane was determined by X-ray diffraction measurement, and the result shows that it belongs to monoclinic crystal system, space group is P2 1/n, with a=0.9284(3...The crystal structure of tetrakis[(pyrrol-1-yl)methyl]methane was determined by X-ray diffraction measurement, and the result shows that it belongs to monoclinic crystal system, space group is P2 1/n, with a=0.9284(3) nm, b=1.0950(6) nm, c=1.8749(8) nm; α=γ= 90.00(4)°, β=103.63(3)°, V=1.8523(14) nm 3, Z=4, ρ calcd. =1.192 kg/m 3, μ=0.072 nm -1 , F(000)=712, R 1=0.0854, wR 2=0.1884. It has been found that the molecules exist in two enantiomeric states. Enantioselective self-assemblies such as one-dimensional molecular stacks in a single handedness, homochiral monolayers and a chiral superlattice are specified in this racemic crystal. In addition, a simple technique is advocated to distinguish chiral states from tetrahedral molecules in the solid state. The present R/S nomenclature of the tetracooradinated carbon centers is used solely for its convenience to distinguish the two enantiomeric states, but not used to determine the absolute configurations.展开更多
Analytical solutions for the elastic properties of a variety of binary nanotubes with arbitrary chirality are obtained through the study of systematic molecular mechanics. This molecular mechanics model is first exten...Analytical solutions for the elastic properties of a variety of binary nanotubes with arbitrary chirality are obtained through the study of systematic molecular mechanics. This molecular mechanics model is first extended to chiral binary nanotubes by introducing an additional out-of-plane inversion term into the so-called stick-spiral model, which results from the polar bonds and the buckling of binary graphitic crystals. The closed-form expressions for the longitudinal and circumferential Young's modulus and Poisson's ratio of chiral binary nanotubes are derived as functions of the tube diameter. The obtained inversion force constants are negative for all types of binary nanotubes, and the predicted tube stiffness is lower than that by the former stick-spiral model without consideration of the inversion term, reflecting the softening effect of the buckling on the elastic properties of binary nanotubes. The obtained properties are shown to be comparable to available density functional theory calculated results and to be chirality and size sensitive. The developed model and explicit solutions provide a systematic understanding of the mechanical performance of binary nanotubes consisting of III-V and II-VI group elements.展开更多
Introduction Chirality is defined as the absence of inversion symmetry,however,it is actually a pseudo-scalar of objects or figures,and does not depend for its definition on any connection to the physical world[1-5]. ...Introduction Chirality is defined as the absence of inversion symmetry,however,it is actually a pseudo-scalar of objects or figures,and does not depend for its definition on any connection to the physical world[1-5]. Logically,chiral molecules may possess other inherent physical quantity that guarantees the connection to the physical world[6,7].展开更多
Both racemate and enantiomer of a novel double helix,binaphthylcyclooctaterthiophene(BN-COTh),which is a DNA-like molecule constructed by two single helices intertwined with each other via covalent bonds,have been syn...Both racemate and enantiomer of a novel double helix,binaphthylcyclooctaterthiophene(BN-COTh),which is a DNA-like molecule constructed by two single helices intertwined with each other via covalent bonds,have been synthesized with two building blocks,cycloocta-tetrathiophene(COTh) and cyclooctadinaphthyldithiophene(CONT) fused together via Negishi coupling reaction.Another homologue,dinaphthylcyclooctaterthiophene(DN-COTh) has been employed together as a model compound.Besides the synthetic work,BN-COTh and DN-COTh have been investigated by studying their crystal structures,spectroscopic behaviors,chiral resolution and chiral characteristics,including circular dichroism(CD) spectra and optical rotations.In addition,the novel crystal of enantiomer of(R,R,R)-BN-COTh has been explored.The enantiomer molecules packing along b-axis to form a larger and extended assembly packing due to intermolecular interactions between the enantiomer molecules and chloroform molecules in crystal.展开更多
A novel type of host-vip recognition systems have been developed on the basis of a Au(Ⅲ) molecular tweezer receptor and chiral Pt(Ⅱ) vips. The complementary host-vip motifs display high non-covalent binding af...A novel type of host-vip recognition systems have been developed on the basis of a Au(Ⅲ) molecular tweezer receptor and chiral Pt(Ⅱ) vips. The complementary host-vip motifs display high non-covalent binding affinity (Ka: ∼10^(4) L/mol) due to the participation of two-fold intermolecular π-π stacking interactions. Both phosphorescence and chirality signals of the Pt(Ⅱ) vips strengthen in the resulting host-vip complexes, because of the cooperative rigidifying and shielding effects rendered by the tweezer receptor. Their intensities can be reversibly switched toward pH changes, by taking advantage of the electronic repulsion effect between the protonated form of tweezer receptor and the positive-charged vips in acidic environments. Overall, the current study demonstrates the feasibility to enhance and modulate phosphorescence and chirality signals simultaneously via molecular tweezer-based host-vip recognition.展开更多
Helix structures at atomic/molecular level have not been found in self-assembled peptide seque nce with less than three residues.Asβ-sheet supramolecular secondary structures have been discovered in solidstate amino ...Helix structures at atomic/molecular level have not been found in self-assembled peptide seque nce with less than three residues.Asβ-sheet supramolecular secondary structures have been discovered in solidstate amino acids,we here report the conjugation of simple N-terminal aryl protecting group could give rise to helical supramolecular secondary structures in solid-state,which determines the optical activities of the adjacent aryl groups.The carboxylic acid-involved asymmetric H-bonds in N-te rminal aryl amino acids induce the emergence of super-helical structures of amino acid residues and aryl groups.In most cases,supramolecular tilted chirality of aryl groups is opposite to that of amino acid sequences,of which handedness and helical pitch are determined by the H-bond modalities.Determining correlation between supramolecular tilted chirality of aryl segments and their chiroptical activities is firstly unveiled,which was verified by the computational results based on density functional theory.Most aryl amino acids self-assembled by nanoprecipitation method via crystallization induced self-assembly into rigid one-dimensional microstructures with ultra-high Young's modulus.This study reveals the generic existence of chiral supramolecular structure s in aggregated amino acid derivatives and gives an in-depth investigation into the structural-property relationships,which could guide the rational design and screening of chiroptical supramolecular materials.展开更多
Polymerization-induced chiral self-assembly(PICSA)is an efficient strategy that not only allows the construction of the supramolecular chiral assemblies in a controlled manner but also can regulate the morphology in s...Polymerization-induced chiral self-assembly(PICSA)is an efficient strategy that not only allows the construction of the supramolecular chiral assemblies in a controlled manner but also can regulate the morphology in situ.Herein,a series of azobenzene-containing block copolymer(Azo-BCP)assemblies with tunable morphologies and supramolecular chirality were obtained through the PICSA strategy.The supramolecular chirality of Azo-BCP assemblies could be regulated by carbon dioxide(CO_(2))stimulus,and completely recovered by bubbling with Ar.A reversible morphology transformation and chiroptical switching process could also be achieved by the alternative 365 nm UV light irradiation and heatingcooling treatment.Moreover,the supramolecular chirality is thermo-responsive and a reversible chiral-achiral switching was successfully realized,which can be reversibly repeated for at least five times.This work provides a feasible strategy for constructing triple stimuli-responsive supramolecular chiral nano-objects in situ.展开更多
The level lifetimes in partner bands of 130Cs have been measured using the Doppler Shift Attenuation method （DSAM）. The high-spin states of 130Cs were populated via fusion evap- oration reaction 124Sn（11B; 5n）130C...The level lifetimes in partner bands of 130Cs have been measured using the Doppler Shift Attenuation method （DSAM）. The high-spin states of 130Cs were populated via fusion evap- oration reaction 124Sn（11B; 5n）130Cs at a beam energy of 65 MeV. The absolute M1 and E2 transition probabilities have been deduced. The results indicate that the partner bands of 130Cs indeed manifest chiral properties.展开更多
High spin states in 107Ag have been studied via the 100Mo （11B, 4n） 107Ag reaction at a beam energy of 60 MeV on the HI-13 tandem accelerator at the China Institute of Atomic Energy. By analyzing the gamma-gamma coi...High spin states in 107Ag have been studied via the 100Mo （11B, 4n） 107Ag reaction at a beam energy of 60 MeV on the HI-13 tandem accelerator at the China Institute of Atomic Energy. By analyzing the gamma-gamma coincidence and their DCO ratios, a new level scheme of 107Ag is presented. The structures for the newly constructed bands are briefly discussed and tentatively assigned to be chiral doublet bands.展开更多
Chirality is a key factor in the biological activity of many biomolecules. Poly（L-lysine）（PLL）, a polypeptide synthesized from L-lysine, is one of the mostly used cationic polymers for gene delivery. The effect of...Chirality is a key factor in the biological activity of many biomolecules. Poly（L-lysine）（PLL）, a polypeptide synthesized from L-lysine, is one of the mostly used cationic polymers for gene delivery. The effect of chirality of polylysine（PL） on its gene delivery remains unknown. Herein, we prepared three polylysines（PLs） with the similar molecular weight but different backbone chiralities including poly（L-lysine）（PLL）, poly（D-lysine）（PDL） and poly（DL-lysine）（PDLL）. The side chains of each PL were modified with propylene oxide（PO） of different chiralities including（R）PO,（S）PO and（R,S）PO. These PL-POs with distinct chirality in main and side chains could condense p DNA into polyplexes. The polyplexes had approximately the same size, zeta potential and binding ability, but showed distinct gene transfection efficiency. We found that the PLs of L-configuration in the main chain had higher transfection efficiency than that of D or DL configuration due to their faster cellular uptake, while the side chain chirality had no effect on transfection efficiency.展开更多
A novel chirality pairing recognition was found between D-and L-amino acid derivatives.Novel spiral alkaloids formed in the recognition reaction.Possible mechanism was proposed for the stereoselective and chemoselecti...A novel chirality pairing recognition was found between D-and L-amino acid derivatives.Novel spiral alkaloids formed in the recognition reaction.Possible mechanism was proposed for the stereoselective and chemoselective reactions.展开更多
Chiral supramolecules prepared by the additive-driven self-assembly of block copolymers provide a facile method to construct helical nanostructures. In this study, we investigated the chiral transfer from chiral tarta...Chiral supramolecules prepared by the additive-driven self-assembly of block copolymers provide a facile method to construct helical nanostructures. In this study, we investigated the chiral transfer from chiral tartaric acid to poly（styrene）-b-poly（ethylene oxide） using small-angle X-ray scattering,transmission electron microscopy, circular dichroism, and vibrational circular dichroism. The results showed that the chirality was transferred to both the segments of block copolymer irrespective of the interaction with the chiral additives and formation of helical phase structure. However, the chirality transfer was carried out using different methods： for poly（ethylene oxide） segments, the chirality transfer was carried out via direct hydrogen bond formation; for polystyrene segments, the chirality transfer was carried out via the cooperative motion of block copolymers during the thermal annealing.展开更多
Single-handed helical silica nanotubes were prepared according to the literature procedures,using the self-assemblies of a pair of chiral cationic low-molecular-weight gelators as the templates.A chirality indicator,...Single-handed helical silica nanotubes were prepared according to the literature procedures,using the self-assemblies of a pair of chiral cationic low-molecular-weight gelators as the templates.A chirality indicator,4,4＇-bis（triethoxysilyl）-1,1＇-biphenyl,was developed to determine the chirality of the silica nanotubes.The chirality of the surfaces and the bulky walls of the silica nanotubes were understood from the twist of the biphenylene rings.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22002138,22372144,22272146,21922202)the Chinese Postdoctoral Science Foundation(No.2021M692714)the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Chirality,ubiquitous in living matter,plays vital roles in a series of physiological processes.The clarification of the multiple functions of chirality in bioapplications may provide innovative methodologies for engineering anti-tumor agents.Nevertheless,the related research has been rarely explored.In this study,the chiral supramolecular l/d-cysteine(Cys)-Zn^(2+)-indocyanine green(ICG)nanoparticles were constructed through the coordination interaction between l/d-Cys and Zn^(2+),followed by the encapsulation of ICG.Experimental findings revealed that the d-Cys-Zn^(2+)-ICG exhibited 17.31 times higher binding affinity toward phospholipid-composed liposomes compared to l-Cys-Zn^(2+)-ICG.Furthermore,driven by chiralityspecific interaction,a 2.07 folds greater cellular internalization of d-Cys-Zn^(2+)-ICG than l-Cys-Zn^(2+)-ICG was demonstrated.Additionally,the triple-level chirality-dependent photothermal,photodynamic and Zn^(2+)releasing anti-tumor effects of l/d Cys-Zn^(2+)-ICG in vitro were verified.As a result,the d-formed nanoparticles achieved 1.93 times higher anti-tumor efficiency than the l-formed ones.The triple-level chirality-mediated anti-tumor effect highlighted in this study underscores the enormous potential of chirality in biomedicine and holds substantial significance in improving cancer therapeutic efficacy.
基金National Natural Science Foundation of China(Nos.22072050,22372066 and 22301090)the Open Research Fund(No.2024JYBKF05)of Key Laboratory of Material Chemistry for Energy Conversion and Storage(HUST)Ministry of Educationthe China Postdoctoral Science Foundation(No.2023M731189)for financial support,and thank the Analytical and Testing Centre at Huazhong University of Science and Technology for measurement.
文摘To get large dissymmetric factor(g_(lum))of organic circularly polarized luminescence(CPL)materials is still a great challenge.Although helical chirality and planar chirality are usual efficient access to enhancement of CPL,they are not combined together to boost CPL.Here,a new tetraphenylethylene(TPE)tetracycle acid helicate bearing both helical chirality and planar chirality was designed and synthesized.Uniquely,synergy of the helical chirality and planar chirality was used to boost CPL signals both in solution and in helical self-assemblies.In the presence of octadecylamine,the TPE helicate could form helical nanofibers that emitted strong CPL signals with an absolute g_(lum)value up to 0.237.Exceptionally,followed by addition of para-phenylenediamine,the g_(lum)value was successively increased to 0.387 due to formation of bigger helical nanofibers.Compared with that of TPE helicate itself,the CPL signal of the self-assemblies was not only magnified by 104-fold but also inversed,which was very rare result for CPL-active materials.Surprisingly,the interaction of TPE helicate with xylylenediamine even gave a gel,which was transformed into suspension by shaking.Unexpectedly,the suspension showed 40-fold stronger CPL signals than the gel with signal direction inversion each other.Using synergy of the helical chirality and planar chirality to significantly boost CPL intensity provides a new strategy in preparation of organic CPL materials having very large g_(lum)value.
文摘In light of the double helix structure hypothesis for photon,we attempt to elucidate the generation mechanism underlying TF(Torsion Field)from both wave and particle perspectives and the enigma surrounding chiral life on Earth by proposing a neutrino-propagation model for TF,which will serve as a crucial key in unraveling the enigma of life’s origins and is promising to trigger a paradigm transformation in future medical and healthcare technologies.
基金financially supported by the POSCO-POSTECH-RIST Convergence Research Center program funded by POSCOthe National Research Foundation (NRF) grant (RS-2024-00462912) funded by the Ministry of Science and ICT (MSIT) of the Korean government+4 种基金partially supported by National Natural Science Foundation of China (Nos. 12274074, 12134013)Natural Science Foundation of Jiangsu Province (BK20242024)China Scholarship Council (202406090137)Postgraduate Research & Practice Innovation Program of Jiangsu Province (KYCX24_0379)the NRF Ph.D. fellowship (RS-202525437554) funded by the Ministry of Education (MOE) of the Korean government
文摘The scale mismatch between nanoscale biomolecules and sub-wavelength light hinders circular dichroism(CD)spectroscopy for chiral small molecule sensing.In this study,we propose a high quality-factor(Q-factor)optical cavity that offers a breakthrough solution to the intrinsic trade-off between optical chirality density and mode loss.A spin-preserving chiral metasurface utilizes bound states in the continuum(BIC)-guided mode resonance(GMR)degenerate modes to achieve a high Q-factor,while ensuring the preservation of chirality purity for circularly polarized light propagating within the cavity via spin-locking mechanism.Experimental results demonstrate that the BIC-GMR degenerate state enables near-perfect transmission CD up to 0.99,without requiring symmetry breaking.Full-wave simulations further predict that this synergistically enhanced system can achieve a Q-factor as high as 10037 and generate a localized field in the molecular interaction region with an optical chirality density enhancement of up to 400-fold,leading to 5025-fold amplification of the CD signal.This study establishes a foundation for detecting low-concentration chiral molecules,reveals high-Q enhancement,and advances chiral toward single-molecule sensitivity,opening new research avenues in chiral biosensing.
基金Supported by the CAS Special Grant for Postgraduate Research,Innovation and Practice~~
文摘Phylogenetic relations of twining chirality of Dioscorea sp.in China were analyzed based on the genes matK,rbcL and trnL;phylogenetic character of higher-level phylogeny of twining plants was analyzed at a high taxon level based on matK gene.A significant phylogenetic framework of chirality was found:(i)based on matK analysis,right-handed Dioscorea species in China congregate completely to form a monophyly;(ii)rbcL and trnL data sets also supported Chinese right-handed Dioscorea a monophyly,although with ex...
基金financial support from the National Natural Science Foundation of China(Nos.21971180 and 92056111)Nature Science Key Basic Research of Jiangsu Province for Higher Education(No.19KJA360006)+3 种基金Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX20_2655)College Students’Innovation and Entrepreneurship Program(No.201910285021Z)the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutionsthe Program of Innovative Research Team of Soochow University。
文摘Chirality,commonly found in organisms,biomolecules and nature such as L-amino acids and D-sugars,has been extensively studied in chemistry and biomedical science.Hence,the demand for simple and efficient construction of chiral structures,especially chiral polymers,has been rapidly growing due to their potential applications in chemosensors,asymmetric catalysis and biological materials.However,most chiral polymers reported are prepared directly from chiral monomers/chiral catalysts,the corresponding strategies usually involve tedious and expensive design and synthesis.Fortunately,chirality induction strategies(such as circularly polarized light,chiral solvation and chiral gelation etc.)have been known to be highly versatile and efficient in producing chirality from achiral polymers.In this feature article,the current research on chirality induction,transfer and application in achiral polymer systems is summarized.Furthermore,this article discusses some basic concepts,seminal studies,recent advances,the structural design principles,as well as perspectives in the construction and applications of chiral polymers derived from achiral monomers,with the hope to attract more interest from researchers and further advance the development of chiral chemistry.
基金the National Natural Science Foundation of China(No.6 0 1710 0 8) and Shanghai Science and TechnologyCom mittee(No.0 2 14 nm0 0 5 )
文摘The crystal structure of tetrakis[(pyrrol-1-yl)methyl]methane was determined by X-ray diffraction measurement, and the result shows that it belongs to monoclinic crystal system, space group is P2 1/n, with a=0.9284(3) nm, b=1.0950(6) nm, c=1.8749(8) nm; α=γ= 90.00(4)°, β=103.63(3)°, V=1.8523(14) nm 3, Z=4, ρ calcd. =1.192 kg/m 3, μ=0.072 nm -1 , F(000)=712, R 1=0.0854, wR 2=0.1884. It has been found that the molecules exist in two enantiomeric states. Enantioselective self-assemblies such as one-dimensional molecular stacks in a single handedness, homochiral monolayers and a chiral superlattice are specified in this racemic crystal. In addition, a simple technique is advocated to distinguish chiral states from tetrahedral molecules in the solid state. The present R/S nomenclature of the tetracooradinated carbon centers is used solely for its convenience to distinguish the two enantiomeric states, but not used to determine the absolute configurations.
基金supported by the 973 Program (Grants 2013CB932604, 2012CB933403)a project funded by the Priority Academic Program Development of Jiangsu Higher Education InstitutionsJiangsu Innovation Program for Graduate Education (Grant CXZZ12_0140)
文摘Analytical solutions for the elastic properties of a variety of binary nanotubes with arbitrary chirality are obtained through the study of systematic molecular mechanics. This molecular mechanics model is first extended to chiral binary nanotubes by introducing an additional out-of-plane inversion term into the so-called stick-spiral model, which results from the polar bonds and the buckling of binary graphitic crystals. The closed-form expressions for the longitudinal and circumferential Young's modulus and Poisson's ratio of chiral binary nanotubes are derived as functions of the tube diameter. The obtained inversion force constants are negative for all types of binary nanotubes, and the predicted tube stiffness is lower than that by the former stick-spiral model without consideration of the inversion term, reflecting the softening effect of the buckling on the elastic properties of binary nanotubes. The obtained properties are shown to be comparable to available density functional theory calculated results and to be chirality and size sensitive. The developed model and explicit solutions provide a systematic understanding of the mechanical performance of binary nanotubes consisting of III-V and II-VI group elements.
基金Supported by the National Natural Science Foundation of China(No.60171008)Shanghai Science and Technology Commit-tee(No.0452nm087).
文摘Introduction Chirality is defined as the absence of inversion symmetry,however,it is actually a pseudo-scalar of objects or figures,and does not depend for its definition on any connection to the physical world[1-5]. Logically,chiral molecules may possess other inherent physical quantity that guarantees the connection to the physical world[6,7].
基金supported by the National Natural Science Foundation of China(Nos.21672053 and 21672054)Innovation Scientists and Technicians Troop Construction Projects of Henan Province(C20150011)。
文摘Both racemate and enantiomer of a novel double helix,binaphthylcyclooctaterthiophene(BN-COTh),which is a DNA-like molecule constructed by two single helices intertwined with each other via covalent bonds,have been synthesized with two building blocks,cycloocta-tetrathiophene(COTh) and cyclooctadinaphthyldithiophene(CONT) fused together via Negishi coupling reaction.Another homologue,dinaphthylcyclooctaterthiophene(DN-COTh) has been employed together as a model compound.Besides the synthetic work,BN-COTh and DN-COTh have been investigated by studying their crystal structures,spectroscopic behaviors,chiral resolution and chiral characteristics,including circular dichroism(CD) spectra and optical rotations.In addition,the novel crystal of enantiomer of(R,R,R)-BN-COTh has been explored.The enantiomer molecules packing along b-axis to form a larger and extended assembly packing due to intermolecular interactions between the enantiomer molecules and chloroform molecules in crystal.
基金financially supported by the National Natural Science Foundation of China(Nos.21922110 and 21871245)the Fundamental Research Funds for the Central Universities(No.WK3450000005)the Starry Night Science Fund at Shanghai Institute for Advanced Study,Zhejiang University(No.SNZJU-SIAS-006)。
文摘A novel type of host-vip recognition systems have been developed on the basis of a Au(Ⅲ) molecular tweezer receptor and chiral Pt(Ⅱ) vips. The complementary host-vip motifs display high non-covalent binding affinity (Ka: ∼10^(4) L/mol) due to the participation of two-fold intermolecular π-π stacking interactions. Both phosphorescence and chirality signals of the Pt(Ⅱ) vips strengthen in the resulting host-vip complexes, because of the cooperative rigidifying and shielding effects rendered by the tweezer receptor. Their intensities can be reversibly switched toward pH changes, by taking advantage of the electronic repulsion effect between the protonated form of tweezer receptor and the positive-charged vips in acidic environments. Overall, the current study demonstrates the feasibility to enhance and modulate phosphorescence and chirality signals simultaneously via molecular tweezer-based host-vip recognition.
基金supported by the Qilu Young Scholarship Funding of Shandong Universitysupported by the National Natural Science Foundation of China(Nos.21872087,21901145)Natural Science Foundation of Jiangsu Province(No.BK20190209)the financial support from Youth cross-scientific innovation group of Shandong University(No.2020QNQT003)。
文摘Helix structures at atomic/molecular level have not been found in self-assembled peptide seque nce with less than three residues.Asβ-sheet supramolecular secondary structures have been discovered in solidstate amino acids,we here report the conjugation of simple N-terminal aryl protecting group could give rise to helical supramolecular secondary structures in solid-state,which determines the optical activities of the adjacent aryl groups.The carboxylic acid-involved asymmetric H-bonds in N-te rminal aryl amino acids induce the emergence of super-helical structures of amino acid residues and aryl groups.In most cases,supramolecular tilted chirality of aryl groups is opposite to that of amino acid sequences,of which handedness and helical pitch are determined by the H-bond modalities.Determining correlation between supramolecular tilted chirality of aryl segments and their chiroptical activities is firstly unveiled,which was verified by the computational results based on density functional theory.Most aryl amino acids self-assembled by nanoprecipitation method via crystallization induced self-assembly into rigid one-dimensional microstructures with ultra-high Young's modulus.This study reveals the generic existence of chiral supramolecular structure s in aggregated amino acid derivatives and gives an in-depth investigation into the structural-property relationships,which could guide the rational design and screening of chiroptical supramolecular materials.
基金financial support from the National Natural Science Foundation of China(Nos.92056111 and 21971180)Nature Science Key Basic Research of Jiangsu Province for Higher Education(No.19KJA360006)+1 种基金Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX202655)the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions supported this work。
文摘Polymerization-induced chiral self-assembly(PICSA)is an efficient strategy that not only allows the construction of the supramolecular chiral assemblies in a controlled manner but also can regulate the morphology in situ.Herein,a series of azobenzene-containing block copolymer(Azo-BCP)assemblies with tunable morphologies and supramolecular chirality were obtained through the PICSA strategy.The supramolecular chirality of Azo-BCP assemblies could be regulated by carbon dioxide(CO_(2))stimulus,and completely recovered by bubbling with Ar.A reversible morphology transformation and chiroptical switching process could also be achieved by the alternative 365 nm UV light irradiation and heatingcooling treatment.Moreover,the supramolecular chirality is thermo-responsive and a reversible chiral-achiral switching was successfully realized,which can be reversibly repeated for at least five times.This work provides a feasible strategy for constructing triple stimuli-responsive supramolecular chiral nano-objects in situ.
基金supported by the Major State Basic Research Development Program (2007CB815000)National Natural Science Foundation of China (Nos. 10775184, 10675171, 10575133, 10575092, 10375092)
文摘The level lifetimes in partner bands of 130Cs have been measured using the Doppler Shift Attenuation method （DSAM）. The high-spin states of 130Cs were populated via fusion evap- oration reaction 124Sn（11B; 5n）130Cs at a beam energy of 65 MeV. The absolute M1 and E2 transition probabilities have been deduced. The results indicate that the partner bands of 130Cs indeed manifest chiral properties.
基金supported by the Major State Basic Research Development Program (2007CB815000)by National Natural Science Foundation of China (Nos. 11175259, 10775098, 10775184, 11075214, 10927507, 10975191, 10675171, 10105015, 10375092, 10575133)Science and Technology Foundation of Shenzhen, China (Nos. 200705 and SY200806270144A)
文摘High spin states in 107Ag have been studied via the 100Mo （11B, 4n） 107Ag reaction at a beam energy of 60 MeV on the HI-13 tandem accelerator at the China Institute of Atomic Energy. By analyzing the gamma-gamma coincidence and their DCO ratios, a new level scheme of 107Ag is presented. The structures for the newly constructed bands are briefly discussed and tentatively assigned to be chiral doublet bands.
基金financially supported by the National Basic Research Program(No.2014CB931900)the National Natural Science Foundation of China(No.21090352)
文摘Chirality is a key factor in the biological activity of many biomolecules. Poly（L-lysine）（PLL）, a polypeptide synthesized from L-lysine, is one of the mostly used cationic polymers for gene delivery. The effect of chirality of polylysine（PL） on its gene delivery remains unknown. Herein, we prepared three polylysines（PLs） with the similar molecular weight but different backbone chiralities including poly（L-lysine）（PLL）, poly（D-lysine）（PDL） and poly（DL-lysine）（PDLL）. The side chains of each PL were modified with propylene oxide（PO） of different chiralities including（R）PO,（S）PO and（R,S）PO. These PL-POs with distinct chirality in main and side chains could condense p DNA into polyplexes. The polyplexes had approximately the same size, zeta potential and binding ability, but showed distinct gene transfection efficiency. We found that the PLs of L-configuration in the main chain had higher transfection efficiency than that of D or DL configuration due to their faster cellular uptake, while the side chain chirality had no effect on transfection efficiency.
基金supports from NSFC(30873141)973 Program(2009CB522300)Hebei University and the State Key Laboratory of Phytochemistry and Plant Resources in West China.
文摘A novel chirality pairing recognition was found between D-and L-amino acid derivatives.Novel spiral alkaloids formed in the recognition reaction.Possible mechanism was proposed for the stereoselective and chemoselective reactions.
基金supported by National Natural Science foundation of China(Nos.21374060 and 21574081)
文摘Chiral supramolecules prepared by the additive-driven self-assembly of block copolymers provide a facile method to construct helical nanostructures. In this study, we investigated the chiral transfer from chiral tartaric acid to poly（styrene）-b-poly（ethylene oxide） using small-angle X-ray scattering,transmission electron microscopy, circular dichroism, and vibrational circular dichroism. The results showed that the chirality was transferred to both the segments of block copolymer irrespective of the interaction with the chiral additives and formation of helical phase structure. However, the chirality transfer was carried out using different methods： for poly（ethylene oxide） segments, the chirality transfer was carried out via direct hydrogen bond formation; for polystyrene segments, the chirality transfer was carried out via the cooperative motion of block copolymers during the thermal annealing.
基金supported by the Natural Science Foundation of Jiangsu Province(No.BK2011354)the Priority Academic Program Development of Jiangsu High Education Institutions(PAPD)the National Natural Science Foundation of China(Nos.21071103 and 21074086)
文摘Single-handed helical silica nanotubes were prepared according to the literature procedures,using the self-assemblies of a pair of chiral cationic low-molecular-weight gelators as the templates.A chirality indicator,4,4＇-bis（triethoxysilyl）-1,1＇-biphenyl,was developed to determine the chirality of the silica nanotubes.The chirality of the surfaces and the bulky walls of the silica nanotubes were understood from the twist of the biphenylene rings.
