Molecular recognition in water,the biological solvent,always receives significant research focus in supramolecular chemistry.The mechanisms of molecular recognition in water is key to comprehending biological processe...Molecular recognition in water,the biological solvent,always receives significant research focus in supramolecular chemistry.The mechanisms of molecular recognition in water is key to comprehending biological processes at the molecular level.Over the past five decades,supramolecular chemists have developed a vast array of synthetic receptors with highly diverse structures and recognition properties.Among them,cyclophanes represent an important family of macrocyclic receptors that have been extensively explored.The aromatic moieties in cyclophanes not only facilitate chemical modifications to impart water solubility but also enable forming hydrophobic cavities for guest inclusion in aqueous environments.Pioneered 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 solutions.This review provides an overview of cyclophane receptors designed to bind organic guests in water.We 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 selectivity.This review aims to inspire the development of novel synthetic receptors with intriguing properties and foster practical applications of cyclophanes.展开更多
Three-residue cyclophane-forming enzymes(3-Cy FEs) are a group of radical S-adenosylmethionine(SAM)enzymes involved in the biosynthesis of ribosomally synthesized and posttranslationally modified peptides(Ri PPs). 3-C...Three-residue cyclophane-forming enzymes(3-Cy FEs) are a group of radical S-adenosylmethionine(SAM)enzymes involved in the biosynthesis of ribosomally synthesized and posttranslationally modified peptides(Ri PPs). 3-Cy FE catalyzes the crosslinking between an aromatic residue(Ω1) and a non-aromatic residue(X3) in a Ω1-X2-X3 motif to produce a cyclophane ring, a key step in the biosynthesis of the Ri PP natural product triceptide. In this study, we perform a genome-wide search for the Xye-type triceptides, showing these Ri PPs are likely class-specific and only present in gamma-proteobacteria. The 3-Cy FE Pau B from Photorhabdus australis exhibits a relaxed substrate specificity on the X3 position, but glycine in this position is not suitable for cyclophane formation. We also reconstituted the activity of Pau B in vitro,showing it produces the N-terminal cyclophane firstly, and then the C-terminal ring, whereas the middle cyclophane is produced in the last step.展开更多
Anion can be identified by pyromellitic imide-azacyclophane which is one of the host compounds.This article investigated the interaction between the host and organic pollution compounds.The host and other eight compou...Anion can be identified by pyromellitic imide-azacyclophane which is one of the host compounds.This article investigated the interaction between the host and organic pollution compounds.The host and other eight compounds were optimized by DFT（density functional theory） B3LYP/6-31G level and the energy of compounds was corrected using Boys-Bemardi method.On the basis of B3LYP/6-31G optimized geometries,the RDG function and sign（λ2（r））ρ（r） function values of space points were calculated,and color RDG isosurface map was drawn.3He chemical shift was calculated by the B3LYP/6-31G method.The results showed that the eight organic pollution molecules with the host one shaped stable configurations by hydrogen bonds,respectively.The stabilization energy of complexes 4 and 7 showed repulsion（steric effects） of cyclophane cage observably affecting the stability of the complexes.The location,intensity and the type of interaction in complex 1 were analyzed through color-filled RDG isosurface map.Aromaticity calculations showed that the weak interaction reduced the transverse induction ring current in the host rings,and deteriorated the aromaticity of compounds.展开更多
Stimuli-responsive macrocycles are of importance for synthetic chemistry and smart materials. In this manuscript, we report two novel organoborane cyclophanes, which were successfully synthesized by ruthenium-catalyze...Stimuli-responsive macrocycles are of importance for synthetic chemistry and smart materials. In this manuscript, we report two novel organoborane cyclophanes, which were successfully synthesized by ruthenium-catalyzed olefin metathesis. They are composed of one/two boron-doped helicene π-skeletons and flexible alkyl chain linkers, thus representing a new kind of non-conjugated organoborane macrocycles. Their cyclic structures and photophysical properties, as well as Lewis acidity were theoretically and experimentally investigated. Notably, two enantiomers in one single crystal are observed for one organoborane cyclophane, owning to the presence of helical π-framework in its cyclic structure. Moreover, their Lewis acid-base adducts may dissociate in the excited state and thus display intriguing photo-responsive fluorescence properties, which can be further modulated by temperature. This study thus provides a novel design strategy for non-conjugated organoborane macrocycles, which may promote the development of stimuli-responsive macrocyclic materials with fascinating properties.展开更多
Benefiting from its bent molecular structure,3,6-pyridazinyl contained tetracationic cyclophane（1） is synthesized by template-directed method with high isolated yield up to 92%.This template-directed strategy is fur...Benefiting from its bent molecular structure,3,6-pyridazinyl contained tetracationic cyclophane（1） is synthesized by template-directed method with high isolated yield up to 92%.This template-directed strategy is further utilized to efficiently construct [2]rotaxane.展开更多
A cationic branch-type cyclophane tetramer (1a) was synthesized by introducing three Boc-protected cyclophane derivatives into a N-acetylated tetraaza[6.1.6.1]paracy-clophane derivative as a core skeleton through DCC ...A cationic branch-type cyclophane tetramer (1a) was synthesized by introducing three Boc-protected cyclophane derivatives into a N-acetylated tetraaza[6.1.6.1]paracy-clophane derivative as a core skeleton through DCC condensation, followed by removal of the external Boc-protecting groups. Cationic cyclophane tetramer 1a exhibited a high affinity toward an anionic and hydrophobic fluorescent guest, TNS, with binding constant of 4.8 × 105 M-1. This value of 1a was about 80-fold larger than that of the corresponding monomeric cyclophane for the identical guest, reflecting multivalent effect on the guest binding. As for electrostatic recognition, the obtained binding constant of 1a was one order of magnitude larger than that of an analogous anionic cyclophane tetramer (1b) for the identical guest. These enhanced guest-binding abilities of 1a were easily evaluated by fluorescence titration experiments.展开更多
Two novel dithia[3.3]metacyclophanes substituted with ethynyl groups were synthesized as small-sized metacyclophanes from the corresponding brominated dithia-metacyclophanes via C-C bond formation reaction. These comp...Two novel dithia[3.3]metacyclophanes substituted with ethynyl groups were synthesized as small-sized metacyclophanes from the corresponding brominated dithia-metacyclophanes via C-C bond formation reaction. These compounds were characterized by using 1H NMR, mass spectrometry and elemental analyses. The exact structures were determined by using X-ray diffraction analyses. X-ray diffraction analysis results revealed that these compounds have anti conformations because of existence of intermolecular π-π interaction and some short contacts in the crystal. The long wavelength fluorescence was observed for one of the compound having a pyrene moiety in solid state because of the existence of the intermolecular π-π interaction between two pyrene units.展开更多
Dendritic cyclophane tetramer and octamer were prepared by aminolysis of succinimidyl ester derivative of tetraaza [6.1.6.1] paracyclophane with the corresponding poly(amidoamine) dendrimers as a scaffold, followed by...Dendritic cyclophane tetramer and octamer were prepared by aminolysis of succinimidyl ester derivative of tetraaza [6.1.6.1] paracyclophane with the corresponding poly(amidoamine) dendrimers as a scaffold, followed by removal of the protecting groups. The present cyclophane tetramer and octamer showed enhanced guest-binding affinities toward fluorescent guests such as 6-p-toluidinonaphthalene-2-sulfonate and 6-anilinonaphthalene-2-sulfonate, in comparison with those of monocyclic cyclophane, reflecting multivalency effects in macrocycles.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22271164,U20A20259)the Fundamental Research Funds for the Central Universitiesthe NCC Fund(No.NCC2020FH04).
文摘Molecular recognition in water,the biological solvent,always receives significant research focus in supramolecular chemistry.The mechanisms of molecular recognition in water is key to comprehending biological processes at the molecular level.Over the past five decades,supramolecular chemists have developed a vast array of synthetic receptors with highly diverse structures and recognition properties.Among them,cyclophanes represent an important family of macrocyclic receptors that have been extensively explored.The aromatic moieties in cyclophanes not only facilitate chemical modifications to impart water solubility but also enable forming hydrophobic cavities for guest inclusion in aqueous environments.Pioneered 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 solutions.This review provides an overview of cyclophane receptors designed to bind organic guests in water.We 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 selectivity.This review aims to inspire the development of novel synthetic receptors with intriguing properties and foster practical applications of cyclophanes.
基金supported by grants from the National Key Research and Development Program (Nos. 2018YFA0900402 and 2021YFA0910501)the National Natural Science Foundation of China (Nos. 21822703, 21921003, and 32070050)+2 种基金the funding of Innovative research team of high-level local universities in Shanghaia key laboratory program of the Education Commission of Shanghai Municipality (No. ZDSYS14005)West Light Foundation of the Chinese Academy of Sciences (No. xbzgzdsys-202105)。
文摘Three-residue cyclophane-forming enzymes(3-Cy FEs) are a group of radical S-adenosylmethionine(SAM)enzymes involved in the biosynthesis of ribosomally synthesized and posttranslationally modified peptides(Ri PPs). 3-Cy FE catalyzes the crosslinking between an aromatic residue(Ω1) and a non-aromatic residue(X3) in a Ω1-X2-X3 motif to produce a cyclophane ring, a key step in the biosynthesis of the Ri PP natural product triceptide. In this study, we perform a genome-wide search for the Xye-type triceptides, showing these Ri PPs are likely class-specific and only present in gamma-proteobacteria. The 3-Cy FE Pau B from Photorhabdus australis exhibits a relaxed substrate specificity on the X3 position, but glycine in this position is not suitable for cyclophane formation. We also reconstituted the activity of Pau B in vitro,showing it produces the N-terminal cyclophane firstly, and then the C-terminal ring, whereas the middle cyclophane is produced in the last step.
文摘Anion can be identified by pyromellitic imide-azacyclophane which is one of the host compounds.This article investigated the interaction between the host and organic pollution compounds.The host and other eight compounds were optimized by DFT（density functional theory） B3LYP/6-31G level and the energy of compounds was corrected using Boys-Bemardi method.On the basis of B3LYP/6-31G optimized geometries,the RDG function and sign（λ2（r））ρ（r） function values of space points were calculated,and color RDG isosurface map was drawn.3He chemical shift was calculated by the B3LYP/6-31G method.The results showed that the eight organic pollution molecules with the host one shaped stable configurations by hydrogen bonds,respectively.The stabilization energy of complexes 4 and 7 showed repulsion（steric effects） of cyclophane cage observably affecting the stability of the complexes.The location,intensity and the type of interaction in complex 1 were analyzed through color-filled RDG isosurface map.Aromaticity calculations showed that the weak interaction reduced the transverse induction ring current in the host rings,and deteriorated the aromaticity of compounds.
基金supported by the National Natural Science Foundation of China (Nos. 22175074, 21822507)。
文摘Stimuli-responsive macrocycles are of importance for synthetic chemistry and smart materials. In this manuscript, we report two novel organoborane cyclophanes, which were successfully synthesized by ruthenium-catalyzed olefin metathesis. They are composed of one/two boron-doped helicene π-skeletons and flexible alkyl chain linkers, thus representing a new kind of non-conjugated organoborane macrocycles. Their cyclic structures and photophysical properties, as well as Lewis acidity were theoretically and experimentally investigated. Notably, two enantiomers in one single crystal are observed for one organoborane cyclophane, owning to the presence of helical π-framework in its cyclic structure. Moreover, their Lewis acid-base adducts may dissociate in the excited state and thus display intriguing photo-responsive fluorescence properties, which can be further modulated by temperature. This study thus provides a novel design strategy for non-conjugated organoborane macrocycles, which may promote the development of stimuli-responsive macrocyclic materials with fascinating properties.
基金the financial support of NNSF of China(Nos.21402069 and 21361011)the Project of Jiangxi Provincial Education Department(No.GJJ14264)
文摘Benefiting from its bent molecular structure,3,6-pyridazinyl contained tetracationic cyclophane（1） is synthesized by template-directed method with high isolated yield up to 92%.This template-directed strategy is further utilized to efficiently construct [2]rotaxane.
文摘A cationic branch-type cyclophane tetramer (1a) was synthesized by introducing three Boc-protected cyclophane derivatives into a N-acetylated tetraaza[6.1.6.1]paracy-clophane derivative as a core skeleton through DCC condensation, followed by removal of the external Boc-protecting groups. Cationic cyclophane tetramer 1a exhibited a high affinity toward an anionic and hydrophobic fluorescent guest, TNS, with binding constant of 4.8 × 105 M-1. This value of 1a was about 80-fold larger than that of the corresponding monomeric cyclophane for the identical guest, reflecting multivalent effect on the guest binding. As for electrostatic recognition, the obtained binding constant of 1a was one order of magnitude larger than that of an analogous anionic cyclophane tetramer (1b) for the identical guest. These enhanced guest-binding abilities of 1a were easily evaluated by fluorescence titration experiments.
文摘Two novel dithia[3.3]metacyclophanes substituted with ethynyl groups were synthesized as small-sized metacyclophanes from the corresponding brominated dithia-metacyclophanes via C-C bond formation reaction. These compounds were characterized by using 1H NMR, mass spectrometry and elemental analyses. The exact structures were determined by using X-ray diffraction analyses. X-ray diffraction analysis results revealed that these compounds have anti conformations because of existence of intermolecular π-π interaction and some short contacts in the crystal. The long wavelength fluorescence was observed for one of the compound having a pyrene moiety in solid state because of the existence of the intermolecular π-π interaction between two pyrene units.
文摘Dendritic cyclophane tetramer and octamer were prepared by aminolysis of succinimidyl ester derivative of tetraaza [6.1.6.1] paracyclophane with the corresponding poly(amidoamine) dendrimers as a scaffold, followed by removal of the protecting groups. The present cyclophane tetramer and octamer showed enhanced guest-binding affinities toward fluorescent guests such as 6-p-toluidinonaphthalene-2-sulfonate and 6-anilinonaphthalene-2-sulfonate, in comparison with those of monocyclic cyclophane, reflecting multivalency effects in macrocycles.
