Pub Date : 2022-12-21DOI: 10.28954/2022.csq.12.001
Ana B. Caballero, P. Gamez, Guglielmo Spinelli
Photodynamic therapy (PDT) uses a combination of molecular oxygen, light and a photosensitizer (PS) to generate singlet oxygen or reactive oxygen species (ROS), which can eradicate tumoral cells. All currently approved PSs for cancer treatment are molecular PSs. To date, no nanoparticlebased PSs are used clinically although it has widely been shown that nanotechnology may help to improve the properties of molecular PSs; for instance, molecular PSs suffer from some intrinsic limitations that undermine their therapeutic efficacy. In the present minireview, the most critical weaknesses exhibited by molecular PSs are described, and the potential use of nanoparticles (NPs) to address them and to reach the clinics is discussed.
{"title":"Nanotechnological approaches to address photosensitizers’ limitations: towards improved clinical applicability of photodynamic therapy","authors":"Ana B. Caballero, P. Gamez, Guglielmo Spinelli","doi":"10.28954/2022.csq.12.001","DOIUrl":"https://doi.org/10.28954/2022.csq.12.001","url":null,"abstract":"Photodynamic therapy (PDT) uses a combination of molecular oxygen, light and a photosensitizer (PS) to generate singlet oxygen or reactive oxygen species (ROS), which can eradicate tumoral cells. All currently approved PSs for cancer treatment are molecular PSs. To date, no nanoparticlebased PSs are used clinically although it has widely been shown that nanotechnology may help to improve the properties of molecular PSs; for instance, molecular PSs suffer from some intrinsic limitations that undermine their therapeutic efficacy. In the present minireview, the most critical weaknesses exhibited by molecular PSs are described, and the potential use of nanoparticles (NPs) to address them and to reach the clinics is discussed.","PeriodicalId":92762,"journal":{"name":"Chemistry squared","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47735392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-06-02DOI: 10.28954/2022.csq.06.001
Fabrice Pointillart, Pierre‐Antoine Bouit, F. Riobé, Carlo Andrea Mattei, Thomas Delouche, B. Lefeuvre, Marie Dallon-Cordier, C. Lalli, O. Cador, Laura Abad Galán, O. Maury
The association of the [Ln(hfac)3(H2O)2] metallic building blocks with the new ligand [1,1’-binaphthalene]-8,8’-diylbis(diphenylphosphine oxide) (L) led to the formation of three mononuclear complexes of formula [Ln(hfac)3(L)] (LnIII = Eu (1), Dy (2) and Yb (3)). The mononuclear character of the compounds is due to the bidentate coordination mode adopted by L to link the metal. L allows the observation of the characteristic visible 5D0 7FJ (J = 0-4) EuIII- and near infrared 2F5/2 2F7/2 YbIII- emissions while 2 is only weakly emissive due to the mismatch between the energy positions of the triplet excited state of the ligand and DyIII emissive state. The magnetic data reveal a field-induced Single-Molecule Magnet (SMM) behavior for 2 and 3 with an efficient suppression of the Quantum Tunneling of the Magnetization (QTM). The slow magnetic relaxation occurs through a Raman process while the Orbach contribution is discarded as confirmed by the correlation with the MJ states energy splitting provided by the luminescence spectrum of 3.
{"title":"Luminescent and Sublimable Binaphthyl-Based Field-Induced Lanthanide Single-Molecule Magnets","authors":"Fabrice Pointillart, Pierre‐Antoine Bouit, F. Riobé, Carlo Andrea Mattei, Thomas Delouche, B. Lefeuvre, Marie Dallon-Cordier, C. Lalli, O. Cador, Laura Abad Galán, O. Maury","doi":"10.28954/2022.csq.06.001","DOIUrl":"https://doi.org/10.28954/2022.csq.06.001","url":null,"abstract":"The association of the [Ln(hfac)3(H2O)2] metallic building blocks with the new ligand [1,1’-binaphthalene]-8,8’-diylbis(diphenylphosphine oxide) (L) led to the formation of three mononuclear complexes of formula [Ln(hfac)3(L)] (LnIII = Eu (1), Dy (2) and Yb (3)). The mononuclear character of the compounds is due to the bidentate coordination mode adopted by L to link the metal. L allows the observation of the characteristic visible 5D0 7FJ (J = 0-4) EuIII- and near infrared 2F5/2 2F7/2 YbIII- emissions while 2 is only weakly emissive due to the mismatch between the energy positions of the triplet excited state of the ligand and DyIII emissive state. The magnetic data reveal a field-induced Single-Molecule Magnet (SMM) behavior for 2 and 3 with an efficient suppression of the Quantum Tunneling of the Magnetization (QTM). The slow magnetic relaxation occurs through a Raman process while the Orbach contribution is discarded as confirmed by the correlation with the MJ states energy splitting provided by the luminescence spectrum of 3.","PeriodicalId":92762,"journal":{"name":"Chemistry squared","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44718850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.28954/2021.csq.09.001
Rosa Diego, O. Roubeau, G. Aromí
Spin crossover (SCO) active solid solutions with formula [FexZn1-x(Me1,3bpp)2](ClO4)2 (x = 0.10, 0.15, 0.22, 0.33, 0.41, 0.48, 0.56 and 0.64, Me1,3bpp is a bis-pyrazolylpyridine) and the complex [Zn(Me1,3bpp)2](ClO4)2 have been prepared and characterized by single crystal X-ray diffraction. The structural data and the powder diffraction patterns of all the compounds have been compared with the reported isostructural molecular crystal [Fe(Me1,3bpp)2](ClO4)2. Increasing amounts of Zn diminishes monotonically the cooperativity of the SCO of the parent Fe(II) complex (T1/2=183 K) and cause a decrease of T1/2 in line with the negative chemical pressure exerted by the Zn(II) complexes on the Fe(II) lattice. The gradual variation of the magnetic properties as the composition changes are paralleled by the evolution of the structural parameters at the molecular, intermolecular and crystal lattice scales. Thermal trapping of a portion of the Fe(II) centers of these alloys by quenching the crystals to 2 K unveils that, upon warming, the temperature of relaxation of the metastable states is almost constant for all compositions.
{"title":"Variations to Spin Crossover in [FexZn(1−x)(Me1,3bpp)2(ClO4)2] molecular alloys examined by Magnetometry and Single Crystal X-Ray Diffraction","authors":"Rosa Diego, O. Roubeau, G. Aromí","doi":"10.28954/2021.csq.09.001","DOIUrl":"https://doi.org/10.28954/2021.csq.09.001","url":null,"abstract":"Spin crossover (SCO) active solid solutions with formula [FexZn1-x(Me1,3bpp)2](ClO4)2 (x = 0.10, 0.15, 0.22, 0.33, 0.41, 0.48, 0.56 and 0.64, Me1,3bpp is a bis-pyrazolylpyridine) and the complex [Zn(Me1,3bpp)2](ClO4)2 have been prepared and characterized by single crystal X-ray diffraction. The structural data and the powder diffraction patterns of all the compounds have been compared with the reported isostructural molecular crystal [Fe(Me1,3bpp)2](ClO4)2. Increasing amounts of Zn diminishes monotonically the cooperativity of the SCO of the parent Fe(II) complex (T1/2=183 K) and cause a decrease of T1/2 in line with the negative chemical pressure exerted by the Zn(II) complexes on the Fe(II) lattice. The gradual variation of the magnetic properties as the composition changes are paralleled by the evolution of the structural parameters at the molecular, intermolecular and crystal lattice scales. Thermal trapping of a portion of the Fe(II) centers of these alloys by quenching the crystals to 2 K unveils that, upon warming, the temperature of relaxation of the metastable states is almost constant for all compositions.","PeriodicalId":92762,"journal":{"name":"Chemistry squared","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69316818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-30DOI: 10.28954/2020.csq.10.001
Basharat Ali, F. Gendron, Xiao-Lei Li, B. L. Guennic, Jinkui Tang
Two C3-symmetric guanidine-based copper triangles bridged by acetates in a cis manner and by chloride anions in a trans manner, respectively gave rise to two antiferromagnetically coupled hexanuclear CuII compounds, namely [Cu6L2Cl(μ-OAc)(DMF)3]·DMF (Cu6) and [Cu6L2(μ-Cl)2(DMF)4] (Cu6Cl)(where L stands for fully deprotonated tris (2-hydroxybenzylidene) triaminoguanidinium chloride, H5L). The experimental magnetic data of the two compounds were analyzed theoretically. A relatively good agreement with the experimental data was obtained when using the wavefunction theory (CASSCF) in combination with DFT (B3LYP) calculations for the very strong antiferromagnetic coupling within the Cu3 triangles (Javg = − 300 cm−1 for Cu6 and Javg = − 250 cm−1 for Cu6Cl), leading to spin-frustrated systems. It is worth mentioning that the electronic structure of each CuII center remains very similar in each complex with a Kramers ground state well separated from the first excited state (over 12000 cm−1) and weakly anisotropic (g∥ ≈ 2.40 and g⊥ ≈ 2.10).
{"title":"Cis and trans linkage of spin frustrated copper triangles creating Cu6 clusters","authors":"Basharat Ali, F. Gendron, Xiao-Lei Li, B. L. Guennic, Jinkui Tang","doi":"10.28954/2020.csq.10.001","DOIUrl":"https://doi.org/10.28954/2020.csq.10.001","url":null,"abstract":"Two C3-symmetric guanidine-based copper triangles bridged by acetates in a cis manner and by chloride anions in a trans manner, respectively gave rise to two antiferromagnetically coupled hexanuclear CuII compounds, namely [Cu6L2Cl(μ-OAc)(DMF)3]·DMF (Cu6) and [Cu6L2(μ-Cl)2(DMF)4] (Cu6Cl)(where L stands for fully deprotonated tris (2-hydroxybenzylidene) triaminoguanidinium chloride, H5L). The experimental magnetic data of the two compounds were analyzed theoretically. A relatively good agreement with the experimental data was obtained when using the wavefunction theory (CASSCF) in combination with DFT (B3LYP) calculations for the very strong antiferromagnetic coupling within the Cu3 triangles (Javg = − 300 cm−1 for Cu6 and Javg = − 250 cm−1 for Cu6Cl), leading to spin-frustrated systems. It is worth mentioning that the electronic structure of each CuII center remains very similar in each complex with a Kramers ground state well separated from the first excited state (over 12000 cm−1) and weakly anisotropic (g∥ ≈ 2.40 and g⊥ ≈ 2.10).","PeriodicalId":92762,"journal":{"name":"Chemistry squared","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49348694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-01-01DOI: 10.28954/2019.csq.06.001
Arnaud Jaoul, Maxime Tricoire, Jules Moutet, Marie Cordier, Carine Clavaguéra, Grégory Nocton
This article relates the synthesis and characterization of novel heterobimetallic complexes containing a low-valent lanthanide, a tetradentate redox non-innocent ligand, viz. the 4,5,9,10-tetraazaphenanthrene, taphen ligand and transition metal fragments of PdMe2 and PtMe2. The experimental results are supported by a theoretical study. Investigation of their reduction properties allowed the formation of isostructural original heterotrimetallic complexes containing two Cp*2Yb fragments and the (taphen)MMe2 (M = Pd and Pt) motifs. These complexes are stable in non-coordinating solvent such as toluene but decompose in coordinating solvents such as thf. Investigation of the internal electron transfer shows that the taphen ligand behaves as a two-electrons reservoir but is capable of transferring back only one electron in thf. This reversible electron(s) transfer is rare in organolanthanide chemistry and show the potential interest of these complexes in reductive chemistry. Additionally, the trinuclear complexes feature odd X-ray crystal structures in which a deviation of symmetry is observed. The latter observation was studied in depth using quantum chemistry calculations highlighting the role of non-covalent weak interactions.
{"title":"Reversible electron transfer in organolanthanide chemistry.","authors":"Arnaud Jaoul, Maxime Tricoire, Jules Moutet, Marie Cordier, Carine Clavaguéra, Grégory Nocton","doi":"10.28954/2019.csq.06.001","DOIUrl":"10.28954/2019.csq.06.001","url":null,"abstract":"<p><p>This article relates the synthesis and characterization of novel heterobimetallic complexes containing a low-valent lanthanide, a tetradentate redox non-innocent ligand, <i>viz.</i> the 4,5,9,10-tetraazaphenanthrene, taphen ligand and transition metal fragments of PdMe<sub>2</sub> and PtMe<sub>2</sub>. The experimental results are supported by a theoretical study. Investigation of their reduction properties allowed the formation of isostructural original heterotrimetallic complexes containing two Cp*<sub>2</sub>Yb fragments and the (taphen)MMe<sub>2</sub> (M = Pd and Pt) motifs. These complexes are stable in non-coordinating solvent such as toluene but decompose in coordinating solvents such as thf. Investigation of the internal electron transfer shows that the taphen ligand behaves as a two-electrons reservoir but is capable of transferring back only one electron in thf. This reversible electron(s) transfer is rare in organolanthanide chemistry and show the potential interest of these complexes in reductive chemistry. Additionally, the trinuclear complexes feature odd X-ray crystal structures in which a deviation of symmetry is observed. The latter observation was studied in depth using quantum chemistry calculations highlighting the role of non-covalent weak interactions.</p>","PeriodicalId":92762,"journal":{"name":"Chemistry squared","volume":"3 1","pages":"1"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6713560/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44842459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-11-20DOI: 10.28954/2018.CSQ.11.001
Rosa F. Brissos, L. Korrodi-Gregório, R. Pérez-Tomás, O. Roubeau, P. Gamez
The use of metallohelicates as potential antiproliferative agents is mostly exemplified by one sole family of supramolecular compounds that is based on bis-iminopyridine ligands. In the present investigation, two other types of metallocylinders have been selected and their potential DNA-binding and cytotoxic properties have been investigated. Hence, two new neutral iron(III) metallosupramolecular compounds have been prepared from bis-β-diketone ligands, and a known cationic iron(II) helicate from bis-pyrazole ligands has been used for comparison purposes. DNA-interaction experiments and cell studies reveal remarkable biological properties for one of the neutral iron cylinders and the positively charged, pyrazole-based helicate, as illustrated by their antiproliferative behaviours, which are far better than those of two well-known compounds, i.e. the most studied metallohelicate in the field and cisplatin.
{"title":"Antiproliferative properties of iron supramolecular cylinders","authors":"Rosa F. Brissos, L. Korrodi-Gregório, R. Pérez-Tomás, O. Roubeau, P. Gamez","doi":"10.28954/2018.CSQ.11.001","DOIUrl":"https://doi.org/10.28954/2018.CSQ.11.001","url":null,"abstract":"The use of metallohelicates as potential antiproliferative agents is mostly exemplified by one sole family of supramolecular compounds that is based on bis-iminopyridine ligands. In the present investigation, two other types of metallocylinders have been selected and their potential DNA-binding and cytotoxic properties have been investigated. Hence, two new neutral iron(III) metallosupramolecular compounds have been prepared from bis-β-diketone ligands, and a known cationic iron(II) helicate from bis-pyrazole ligands has been used for comparison purposes. DNA-interaction experiments and cell studies reveal remarkable biological properties for one of the neutral iron cylinders and the positively charged, pyrazole-based helicate, as illustrated by their antiproliferative behaviours, which are far better than those of two well-known compounds, i.e. the most studied metallohelicate in the field and cisplatin.","PeriodicalId":92762,"journal":{"name":"Chemistry squared","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41597773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-10-31DOI: 10.28954/2018.CSQ.10.001
Antoine Labrunie, G. Londi, S. Dayneko, Martine Blais, S. Dabos-Seignon, G. Welch, D. Beljonne, P. Blanchard, C. Cabanetos
The synthesis, characterization and use of a new donor-acceptor molecular dyad in single component organic solar cells are reported. The dyad, composed of a triazatruxene-based push-pull 'donor' unit linked to a C60 'acceptor' unit through a non-conjugated σ connector, led to promising power conversion efficiencies of 0.6% when embedded in simple devices exhibiting the architecture: indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene): polystyrene sulfonic acid (PEDOT:PSS)/dyad/Al.
{"title":"A triazatruxene-based molecular dyad for single-component organic solar cells","authors":"Antoine Labrunie, G. Londi, S. Dayneko, Martine Blais, S. Dabos-Seignon, G. Welch, D. Beljonne, P. Blanchard, C. Cabanetos","doi":"10.28954/2018.CSQ.10.001","DOIUrl":"https://doi.org/10.28954/2018.CSQ.10.001","url":null,"abstract":"The synthesis, characterization and use of a new donor-acceptor molecular dyad in single component organic solar cells are reported. The dyad, composed of a triazatruxene-based push-pull 'donor' unit linked to a C60 'acceptor' unit through a non-conjugated σ connector, led to promising power conversion efficiencies of 0.6% when embedded in simple devices exhibiting the architecture: indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene): polystyrene sulfonic acid (PEDOT:PSS)/dyad/Al.","PeriodicalId":92762,"journal":{"name":"Chemistry squared","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42144980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-07-17DOI: 10.28954/2018.CSQ.07.001
G. Chastanet, C. Desplanches, C. Baldé, P. Rosa, M. Marchivie, P. Guionneau
Light-Induced Excited Spin-State Trapping has been studied since 1982 in solution and 1984 in solid state as it offers a reversible way of photoswitching the electronic configuration of spin crossover systems. Since then, the lifetime of the photo-induced state was deeply investigated through kinetics measurements. In 1998, a fast and easy way to record the limit temperature above which the photo-induced state is erased, denoted T(LIESST), was introduced. This procedure has been widely used in the spin crossover community due to its easiness and its efficiency to provide detailed information on the photo-induced state. Correlations between T(LIESST) and structural parameters have been proposed for instance. However, it intrinsically contains drawbacks that can lead to misinterpretation of behaviours and can lead to an over estimation of its scope. This review aims to present and discuss not only the correct way to measure T(LIESST) but also the essential contributions it has brought and the limits not to be exceeded in its interpretation.
{"title":"A critical review of the T(LIESST) temperature in spin crossover materials − What it is and what it is not","authors":"G. Chastanet, C. Desplanches, C. Baldé, P. Rosa, M. Marchivie, P. Guionneau","doi":"10.28954/2018.CSQ.07.001","DOIUrl":"https://doi.org/10.28954/2018.CSQ.07.001","url":null,"abstract":"Light-Induced Excited Spin-State Trapping has been studied since 1982 in solution and 1984 in solid state as it offers a reversible way of photoswitching the electronic configuration of spin crossover systems. Since then, the lifetime of the photo-induced state was deeply investigated through kinetics measurements. In 1998, a fast and easy way to record the limit temperature above which the photo-induced state is erased, denoted T(LIESST), was introduced. This procedure has been widely used in the spin crossover community due to its easiness and its efficiency to provide detailed information on the photo-induced state. Correlations between T(LIESST) and structural parameters have been proposed for instance. However, it intrinsically contains drawbacks that can lead to misinterpretation of behaviours and can lead to an over estimation of its scope. This review aims to present and discuss not only the correct way to measure T(LIESST) but also the essential contributions it has brought and the limits not to be exceeded in its interpretation.","PeriodicalId":92762,"journal":{"name":"Chemistry squared","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46834568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：