Two Gd_(2)complexes,namely[Gd_(2)(dbm)_(2)(HL_(1))_(2)(CH_(3)OH)_(2)]·4CH_(3)OH(1)and[Gd_(2)(dbm)_(2)(L_(2))_(2)(CH_(3)OH)_(2)]·2CH_(3)OH(2),where H_(3)L_(1)=(Z)-N'-[4-(diethylamino)-2-hydroxybenzylidene...Two Gd_(2)complexes,namely[Gd_(2)(dbm)_(2)(HL_(1))_(2)(CH_(3)OH)_(2)]·4CH_(3)OH(1)and[Gd_(2)(dbm)_(2)(L_(2))_(2)(CH_(3)OH)_(2)]·2CH_(3)OH(2),where H_(3)L_(1)=(Z)-N'-[4-(diethylamino)-2-hydroxybenzylidene]-2-hydroxyacetohydrazide,H_(2)L_(2)=(E)-N'-(5-bromo-2-hydroxy-3-methoxybenzylidene)nicotinohydrazide,Hdbm=dibenzoylmethane,have been constructed by adopting the solvothermal method.Structural characterization unveils that both complexes 1 and 2 are constituted by two Gd^(3+)ions,two dbm-ions,two CH_(3)OH molecules,and two polydentate Schiff-base ligands(HL_(1)^(2-)or L_(2)^(2-)).In addition,complex 1 contains four free methanol molecules,whereas complex 2 harbors two free methanol molecules.By investigating the interactions between complexes 1 and 2 and four types of bacteria(Bacillus subtilis,Escherichia coli,Staphylococcus aureus,Candida albicans),it was found that both complexes 1 and 2 exhibited potent antibacte-rial activities.The interaction mechanisms between the ligands H_(3)L_(1),H_(2)L_(2),complexes 1 and 2,and calf thymus DNA(CT-DNA)were studied using ultraviolet-visible spectroscopy,fluorescence titration,and cyclic voltammetry.The results demonstrated that both complexes 1 and 2 can intercalate into CT-DNA molecules,thereby inhibiting bacterial proliferation to achieve the antibacterial effects.CCDC:2401116,1;2401117,2.展开更多
Two new complexes,[Zn_(2)(L1)(HL1)(NO_(3))]·CH_(3)OH(1)and[Zn_(3)(L2)(L3)_(3)Cl]·CH_(3)OH(2),were successfully synthesized by‘one-pot’method based on cinnoline-3-ylhydrazine ligand and zinc with 2-hydroxy-...Two new complexes,[Zn_(2)(L1)(HL1)(NO_(3))]·CH_(3)OH(1)and[Zn_(3)(L2)(L3)_(3)Cl]·CH_(3)OH(2),were successfully synthesized by‘one-pot’method based on cinnoline-3-ylhydrazine ligand and zinc with 2-hydroxy-4-methoxybenzaldehyde and 2-hydroxy-3-methoxybenzaldehyde ligands,respectively,where H_(2)L1=5-methoxy-2-(phthalazin-1-ylhydrazonomethyl)-phenol,H_(2)L2=2-methoxy-6-(phthalazin-1-yl-hydrazonomethyl)-phenol,HL3=2-(1,8-dihydro-[1,2,4]triazolo[3,4-α]phthalazin-3-yl)-6-methoxy-phenol.Complexes 1 and 2 were characterized by infrared spectroscopy,elemental analysis,single-crystal X-ray diffraction,powder X-ray diffraction,etc.It is worth noting that the cinnolin-3-yl-hydrazine ligand and 2-hydroxy-3-methoxybenzaldehyde form two types of Schiff bases(H_(2)L2 and HL3)when in situ reacting and coordinating with Zn(Ⅱ),and HL3 also has two coordination modes.In addition,the fluorescence performance showed that complex 1 can achieve selective and sensitive sensing of Al^(3+)in water with a detection limit of 6.37μmol·L^(-1).CCDC:2413978,1;2413979,2.展开更多
A tetranuclear Ln(Ⅲ)-based complex:[Dy_(4)(dbm)_(4)(L)_(6)(μ_(3)-OH)_(2)]·CH_(3)CN(1)(HL=5-[(4-methylbenzylidene)amino]quinolin-8-ol,Hdbm=dibenzoylmethane)was manufactured and its structure was characterized in...A tetranuclear Ln(Ⅲ)-based complex:[Dy_(4)(dbm)_(4)(L)_(6)(μ_(3)-OH)_(2)]·CH_(3)CN(1)(HL=5-[(4-methylbenzylidene)amino]quinolin-8-ol,Hdbm=dibenzoylmethane)was manufactured and its structure was characterized in detail.Xray diffraction analysis shows that complex 1 belongs to the monoclinic crystal system and its space group is P2_1/n,which contains a rhombic Dy_(4)core.Magnetic measurements of 1 suggest it possesses extraordinary single-molecule magnet(SMM)behavior.Its energy barrier U_(eff)/k_(B)was 116.7 K,and the pre-exponential coefficient τ_(0)=1.05×10~(-8)s.CCDC:2359322.展开更多
A[3+4]annulation of α-substituted allenes and Schiff bases is reported.This methodology serves as a conduit for the construction of a series of biologically important benzazepine derivatives in good to excellent yiel...A[3+4]annulation of α-substituted allenes and Schiff bases is reported.This methodology serves as a conduit for the construction of a series of biologically important benzazepine derivatives in good to excellent yields under mild conditions by an unprecedented mode involving β’-carbon of α-substituted allenes and the proposed mechanism is supported by capturing the intermediate.Moreover,this class of benzazepine derivatives exhibited potential ability of cytotoxicity toward cancer cells.展开更多
Since their discovery by Hugo Schiff in 1864,Schiff bases and their metal complexes have gained recognition for their catalytic and biological properties.These compounds exhibit diverse functionalities,serving as cata...Since their discovery by Hugo Schiff in 1864,Schiff bases and their metal complexes have gained recognition for their catalytic and biological properties.These compounds exhibit diverse functionalities,serving as catalysts in synthetic processes and displaying notable biological activities such as antifungal,antibacterial,anti-malarial,and antiviral effects.In various applications,Schiff bases serve as versatile tools,particularly in sensing appli-cations.Through coordination with various metal ions,they form stable complexes.They are utilized as fluo-rescent turn-on/turn-off sensors for detecting a wide range of analytes.The coordination ability makes them valuable as chemosensor for detecting environmentally and biologically important analytes.This review provides a thorough overview of Schiff base chemosensors designed for the detection of environmental and biological significance including metal cations,anions,and neutral analytes.It is structured into four focused sections.The first section addresses the use of Schiff base chemosensor for the selective detection of various metal cations,including Ca^(2+),Al^(3+),Cr^(3+),Mn^(2+),Fe^(3+),Ni^(2+),Cu^(2+),Zn^(2+),Cd^(2+),Hg^(2+),and Pb^(2+);The second section examines the application of fluorescent Schiff base sensors in detecting diverse anions such as F^(-),CN^(-),I^(-),and HSO_(4)^(-);The third section investigates the use of Schiff base fluorescent probes for accurate pH detection and determination;and the fourth section explores the utilization of Schiff base sensors for detecting environmentally and biolog-ically important neutral analytes,including insecticides,pesticides,and others.Additionally,the Schiff base chemosensors for metal cations and anions section are concluded with a table,summarizing the reviewed fluorescent Schiff base sensors for enhanced clarity.展开更多
Luminescent nanoclusters(NCs)have attracted much attention because of their superior photophysical properties;however,the design of dynamic NCs with reversible structural change is highly challenging.Herein,we synthes...Luminescent nanoclusters(NCs)have attracted much attention because of their superior photophysical properties;however,the design of dynamic NCs with reversible structural change is highly challenging.Herein,we synthesize a kind of dynamic luminescent NCs through Schiff base crosslinking between triethylenetetramine(TETA)and tannic acid at room temperature.The proposed NCs have an excitation-independent blue emission,and the maximum emission is available at about 458 nm with two excitation centers.Furthermore,the crosslinking degree of the NCs can be effectively adjusted by TETA and their formation is a kineticcontrol process.Most importantly,the proposed NCs show a property of pHcontrolled reversible depolymerization and polymerization,accompanied by a cyclic“on-off-on”photoswitching,which is directly attributed to pH-stimulated reversible C=N bond cleavage and re-formation.Because of the reversible structure change properties,the dynamic NCs have been well used in reversible information encryption.This new finding provides not only us with a powerful strategy to study the structure–properties relationship of luminescent NCs but also a design idea for constructing smart optical nanomaterials.展开更多
Twelve new Schiff bases of thiadiazole have been synthesized for the first time. Their physical constants, UV, IR, 1H NMR and elementary analysis were originally characterized, biological activity were originally stud...Twelve new Schiff bases of thiadiazole have been synthesized for the first time. Their physical constants, UV, IR, 1H NMR and elementary analysis were originally characterized, biological activity were originally studied. It is found from the results of biological activity tests that some compounds have a remarkable activity on plant growth hormone. Compounds Ⅲa and Ⅲk have a good activity on cytokinin, compounds Ⅲe and Ⅲj and Ⅲl have an excellent activity on auxin.展开更多
文摘Two Gd_(2)complexes,namely[Gd_(2)(dbm)_(2)(HL_(1))_(2)(CH_(3)OH)_(2)]·4CH_(3)OH(1)and[Gd_(2)(dbm)_(2)(L_(2))_(2)(CH_(3)OH)_(2)]·2CH_(3)OH(2),where H_(3)L_(1)=(Z)-N'-[4-(diethylamino)-2-hydroxybenzylidene]-2-hydroxyacetohydrazide,H_(2)L_(2)=(E)-N'-(5-bromo-2-hydroxy-3-methoxybenzylidene)nicotinohydrazide,Hdbm=dibenzoylmethane,have been constructed by adopting the solvothermal method.Structural characterization unveils that both complexes 1 and 2 are constituted by two Gd^(3+)ions,two dbm-ions,two CH_(3)OH molecules,and two polydentate Schiff-base ligands(HL_(1)^(2-)or L_(2)^(2-)).In addition,complex 1 contains four free methanol molecules,whereas complex 2 harbors two free methanol molecules.By investigating the interactions between complexes 1 and 2 and four types of bacteria(Bacillus subtilis,Escherichia coli,Staphylococcus aureus,Candida albicans),it was found that both complexes 1 and 2 exhibited potent antibacte-rial activities.The interaction mechanisms between the ligands H_(3)L_(1),H_(2)L_(2),complexes 1 and 2,and calf thymus DNA(CT-DNA)were studied using ultraviolet-visible spectroscopy,fluorescence titration,and cyclic voltammetry.The results demonstrated that both complexes 1 and 2 can intercalate into CT-DNA molecules,thereby inhibiting bacterial proliferation to achieve the antibacterial effects.CCDC:2401116,1;2401117,2.
文摘Two new complexes,[Zn_(2)(L1)(HL1)(NO_(3))]·CH_(3)OH(1)and[Zn_(3)(L2)(L3)_(3)Cl]·CH_(3)OH(2),were successfully synthesized by‘one-pot’method based on cinnoline-3-ylhydrazine ligand and zinc with 2-hydroxy-4-methoxybenzaldehyde and 2-hydroxy-3-methoxybenzaldehyde ligands,respectively,where H_(2)L1=5-methoxy-2-(phthalazin-1-ylhydrazonomethyl)-phenol,H_(2)L2=2-methoxy-6-(phthalazin-1-yl-hydrazonomethyl)-phenol,HL3=2-(1,8-dihydro-[1,2,4]triazolo[3,4-α]phthalazin-3-yl)-6-methoxy-phenol.Complexes 1 and 2 were characterized by infrared spectroscopy,elemental analysis,single-crystal X-ray diffraction,powder X-ray diffraction,etc.It is worth noting that the cinnolin-3-yl-hydrazine ligand and 2-hydroxy-3-methoxybenzaldehyde form two types of Schiff bases(H_(2)L2 and HL3)when in situ reacting and coordinating with Zn(Ⅱ),and HL3 also has two coordination modes.In addition,the fluorescence performance showed that complex 1 can achieve selective and sensitive sensing of Al^(3+)in water with a detection limit of 6.37μmol·L^(-1).CCDC:2413978,1;2413979,2.
文摘A tetranuclear Ln(Ⅲ)-based complex:[Dy_(4)(dbm)_(4)(L)_(6)(μ_(3)-OH)_(2)]·CH_(3)CN(1)(HL=5-[(4-methylbenzylidene)amino]quinolin-8-ol,Hdbm=dibenzoylmethane)was manufactured and its structure was characterized in detail.Xray diffraction analysis shows that complex 1 belongs to the monoclinic crystal system and its space group is P2_1/n,which contains a rhombic Dy_(4)core.Magnetic measurements of 1 suggest it possesses extraordinary single-molecule magnet(SMM)behavior.Its energy barrier U_(eff)/k_(B)was 116.7 K,and the pre-exponential coefficient τ_(0)=1.05×10~(-8)s.CCDC:2359322.
基金financially supported by the National Natural Science Foundation of China(No.21572271).
文摘A[3+4]annulation of α-substituted allenes and Schiff bases is reported.This methodology serves as a conduit for the construction of a series of biologically important benzazepine derivatives in good to excellent yields under mild conditions by an unprecedented mode involving β’-carbon of α-substituted allenes and the proposed mechanism is supported by capturing the intermediate.Moreover,this class of benzazepine derivatives exhibited potential ability of cytotoxicity toward cancer cells.
文摘Since their discovery by Hugo Schiff in 1864,Schiff bases and their metal complexes have gained recognition for their catalytic and biological properties.These compounds exhibit diverse functionalities,serving as catalysts in synthetic processes and displaying notable biological activities such as antifungal,antibacterial,anti-malarial,and antiviral effects.In various applications,Schiff bases serve as versatile tools,particularly in sensing appli-cations.Through coordination with various metal ions,they form stable complexes.They are utilized as fluo-rescent turn-on/turn-off sensors for detecting a wide range of analytes.The coordination ability makes them valuable as chemosensor for detecting environmentally and biologically important analytes.This review provides a thorough overview of Schiff base chemosensors designed for the detection of environmental and biological significance including metal cations,anions,and neutral analytes.It is structured into four focused sections.The first section addresses the use of Schiff base chemosensor for the selective detection of various metal cations,including Ca^(2+),Al^(3+),Cr^(3+),Mn^(2+),Fe^(3+),Ni^(2+),Cu^(2+),Zn^(2+),Cd^(2+),Hg^(2+),and Pb^(2+);The second section examines the application of fluorescent Schiff base sensors in detecting diverse anions such as F^(-),CN^(-),I^(-),and HSO_(4)^(-);The third section investigates the use of Schiff base fluorescent probes for accurate pH detection and determination;and the fourth section explores the utilization of Schiff base sensors for detecting environmentally and biolog-ically important neutral analytes,including insecticides,pesticides,and others.Additionally,the Schiff base chemosensors for metal cations and anions section are concluded with a table,summarizing the reviewed fluorescent Schiff base sensors for enhanced clarity.
基金supported by the National Natural Science Foundation of China(52273197 and 52333007)Shenzhen Key Laboratory of Functional Aggregate Materials(ZDSYS20211021111400001)+2 种基金the Science and Technology Plan of Shenzhen(JCYJ2021324134613038,JCYJ20220818103007014,KQTD20210811090142053,GJHZ20210705141810031)the Innovation and Technology Commission(ITC-CNERC14SC01)Tianjin Key Medical Discipline(Specialty)Construction Project.
文摘Luminescent nanoclusters(NCs)have attracted much attention because of their superior photophysical properties;however,the design of dynamic NCs with reversible structural change is highly challenging.Herein,we synthesize a kind of dynamic luminescent NCs through Schiff base crosslinking between triethylenetetramine(TETA)and tannic acid at room temperature.The proposed NCs have an excitation-independent blue emission,and the maximum emission is available at about 458 nm with two excitation centers.Furthermore,the crosslinking degree of the NCs can be effectively adjusted by TETA and their formation is a kineticcontrol process.Most importantly,the proposed NCs show a property of pHcontrolled reversible depolymerization and polymerization,accompanied by a cyclic“on-off-on”photoswitching,which is directly attributed to pH-stimulated reversible C=N bond cleavage and re-formation.Because of the reversible structure change properties,the dynamic NCs have been well used in reversible information encryption.This new finding provides not only us with a powerful strategy to study the structure–properties relationship of luminescent NCs but also a design idea for constructing smart optical nanomaterials.
文摘Twelve new Schiff bases of thiadiazole have been synthesized for the first time. Their physical constants, UV, IR, 1H NMR and elementary analysis were originally characterized, biological activity were originally studied. It is found from the results of biological activity tests that some compounds have a remarkable activity on plant growth hormone. Compounds Ⅲa and Ⅲk have a good activity on cytokinin, compounds Ⅲe and Ⅲj and Ⅲl have an excellent activity on auxin.
