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1.
Ida Vang Andersen Rocío García-Vzquez Umberto Maria Battisti Matthias M. Herth 《Molecules (Basel, Switzerland)》2022,27(13)
Radiolabeling of tetrazines has gained increasing attention due to their important role in pretargeted imaging or therapy. The most commonly used radionuclide in PET imaging is fluorine-18. For this reason, we have recently developed a method which enables the direct aromatic 18F-fluorination of tetrazines using stannane precursors through copper-mediated fluorinations. Herein, we further optimized this labeling procedure. 3-(3-fluorophenyl)-1,2,4,5-tetrazine was chosen for this purpose because of its high reactivity and respective limited stability during the labeling process. By optimizing parameters such as elution conditions, precursor amount, catalyst, time or temperature, the radiochemical yield (RCY) could be increased by approximately 30%. These conditions were then applied to optimize the RCY of a recently successfully developed and promising pretargeting imaging agent. This agent could be isolated in a decay corrected RCY of 14 ± 3% and Am of 201 ± 30 GBq/µmol in a synthesis time of 70 min. Consequently, the RCY increased by 27%. 相似文献
2.
Alice K. Hui Chun‐Hsing Chen Adam M. Terwilliger Richard L. Lord Kenneth G. Caulton 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(3):250-255
Reaction of a bis‐tetrazinyl pyridine pincer ligand, btzp, with a vanadium(III) reagent gives not a simple adduct but dichlorido{3‐methyl‐6‐[6‐(6‐methyl‐1,2,4,5‐tetrazin‐3‐yl‐κN2)pyridin‐2‐yl‐κN]‐1,4‐dihydro‐1,2,4,5‐tetrazin‐1‐yl‐κN1}oxidovanadium(IV) acetonitrile 2.5‐solvate, [V(C11H10N9)Cl2O]·2.5CH3CN, a species which X‐ray diffraction reveals to have one H atom added to one of the two tetrazinyl rings. This H atom was first revealed by a short intermolecular N...Cl contact in the unit cell and subsequently established, from difference maps, to be associated with a hydrogen bond. One chloride ligand has also been replaced by an oxide ligand in this synthetic reaction. This formula for the complex, [V(Hbtzp)Cl2O], leaves open the question of both ligand oxidation state and spin state. A computational study of all isomeric locations of the H atom shows the similarity of their energies, which is subject to perturbation by intermolecular hydrogen bonding found in X‐ray work on the solid state. These density functional calculations reveal that the isomer with the H atom located as found in the solid state contains a neutral radical Hbtzp ligand and tetravalent d1 V center, but that these two unpaired electrons are more stable as an open‐shell singlet and hence antiferromagnetically coupled. 相似文献
3.
Greta Linden Prof. Dr. Olalla Vázquez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(44):10014-10023
Photodynamic therapy (PDT) leads to cancer remission via the production of cytotoxic species under photosensitizer (PS) irradiation. However, concomitant damage and dark toxicity can both hinder its use. With this in mind, we have implemented a versatile peptide-based platform of bioorthogonally activatable BODIPY-tetrazine PSs. Confocal microscopy and phototoxicity studies demonstrated that the incorporation of the PS, as a bifunctional module, into a peptide enabled spatial and conditional control of singlet oxygen (1O2) generation. Comparing subcellular distribution, PS confined in the cytoplasmic membrane achieved the highest toxicities (IC50=0.096±0.003 μm ) after activation and without apparent dark toxicity. Our tunable approach will inspire novel probes towards smart PDT. 相似文献
4.
Synthesis,Characterization, and Energetic Properties of 6‐Amino‐tetrazolo[1,5‐b]‐1,2,4,5‐tetrazine‐7‐N‐oxide: A Nitrogen‐Rich Material with High Density
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The synthesis and energetic properties of a novel N‐oxide high‐nitrogen compound, 6‐amino‐tetrazolo[1,5‐b]‐1,2,4,5‐tetrazine‐7‐N‐oxide, are described. Resulting from the N‐oxide and fused rings system, this molecule exhibits high density, excellent detonation properties, and acceptable impact and friction sensitivities, which suggests potential applications as an energetic material. Compared to known high‐nitrogen compounds, such as 3,6‐diazido‐1,2,4,5‐tetrazine (DiAT), 2,4,6‐tri(azido)‐1,3,5‐triazine (TAT), and 4,4′,6,6′‐tetra(azido)azo‐1,3,5‐triazine (TAAT), a marked performance and stability increase is seen. This supports the superior qualities of this new compound and the advantage of design strategy. 相似文献
5.
Strong Direct Magnetic Coupling in a Dinuclear CoII Tetrazine Radical Single‐Molecule Magnet
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Toby J. Woods Dr. Maria Fernanda Ballesteros‐Rivas Sergei M. Ostrovsky Andrew V. Palii Oleg S. Reu Sophia I. Klokishner Dr. Kim R. Dunbar 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(29):10302-10305
The ligand‐centered radical complex [(CoTPMA)2‐μ‐bmtz.?](O3SCF3)3 ? CH3CN (bmtz=3,6‐bis(2′‐pyrimidyl)‐1,2,4,5‐tetrazine, TPMA=tris‐(2‐pyridylmethyl)amine) has been synthesized from the neutral bmtz precursor. Single‐crystal X‐ray diffraction studies have confirmed the presence of the ligand‐centered radical. The CoII complex exhibits slow paramagnetic relaxation in an applied DC field with a barrier to spin reversal of 39 K. This behavior is a result of strong antiferromagnetic metal–radical coupling combined with positive axial and strong rhombic anisotropic contributions from the CoII ions. 相似文献
6.
The pretargeting strategy has recently emerged in order to overcome the limitations of direct targeting, mainly in the field of radioimmunotherapy (RIT). This strategy is directly dependent on chemical reactions, namely bioorthogonal reactions, which have been developed for their ability to occur under physiological conditions. The Staudinger ligation, the copper catalyzed azide-alkyne cycloaddition (CuAAC) and the strain-promoted [3 + 2] azide–alkyne cycloaddition (SPAAC) were the first bioorthogonal reactions introduced in the literature. However, due to their incomplete biocompatibility and slow kinetics, the inverse-electron demand Diels-Alder (IEDDA) reaction was advanced in 2008 by Blackman et al. as an optimal bioorthogonal reaction. The IEDDA is the fastest bioorthogonal reaction known so far. Its biocompatibility and ideal kinetics are very appealing for pretargeting applications. The use of a trans-cyclooctene (TCO) and a tetrazine (Tz) in the reaction encouraged researchers to study them deeply. It was found that both reagents are sensitive to acidic or basic conditions. Furthermore, TCO is photosensitive and can be isomerized to its cis-conformation via a radical catalyzed reaction. Unfortunately, the cis-conformer is significantly less reactive toward tetrazine than the trans-conformation. Therefore, extensive research has been carried out to optimize both click reagents and to employ the IEDDA bioorthogonal reaction in biomedical applications. 相似文献
7.
Romain Plais Guy Gouarin Dr. Anne Gaucher Violette Haldys Arnaud Brosseau Dr. Gilles Clavier Dr. Jean-Yves Salpin Prof. Dr. Damien Prim 《Chemphyschem》2020,21(12):1249-1257
The intrinsic properties of tetrazine as a π-anion receptor and as an on/off recognition probe merged with H-bond ability of an urea motif into a single architecture constitutes a new generation of well-defined anion receptors. Complexation properties directly benefit from the dual and synergistic contribution of tetrazine and urea. In this study, we report on the synthesis and assessment of binding properties to anions of diverse geometries. Association constants have been predicted by theoretical calculations and evaluated by multiple and complementary experimental techniques including electrospray-mass tandem spectroscopy, NMR, UV-visible, steady state fluorescence spectroscopies and time resolved fluorescence. These results provide the basis for a better understanding of both the complexation and the anion-dependent quenching mechanism. 相似文献
8.
A. E. Frumkin A. M. Churakov Yu. A. Strelenko V. A. Tartakovsky 《Russian Chemical Bulletin》2000,49(3):482-486
A new approach to the synthesis of benzo[e][1,2,3,4]tetrazine 1,3-dioxides involves the treatment ofN-nitroanilines containing anortho-(tert-butyl-NNO-azoxy) group with phosphoric anhydride or phosphorus pentachloride. The reaction is supposed to proceed through an intermediate
diazonium oxide cation.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya. No. 3, pp. 480–484, March, 2000. 相似文献
9.
Various bioorthogonal chemistries have been used for fluorescent imaging owing to the advantageous reactions they employ. Recent advances in bioorthogonal chemistry have revolutionized labeling strategies for fluorescence imaging, with inverse electron demand Diels–Alder (iEDDA) reactions in particular attracting recent attention owing to their fast kinetics and excellent specificity. One of the most interesting features of the iEDDA labeling strategy is that tetrazine-functionalized dyes are known to act as fluorogenic probes. In this review, we will focus on the synthesis, molecular-design strategies, and bioimaging applications of tetrazine-functionalized fluorogenic probes. Traditional Pinner reaction and “Pinner-like” reactions for tetrazine synthesis are discussed here, as well as metal-catalyzed C–C bond formations with convenient tetrazine intermediates and the fabrication of tetrazine-conjugated fluorophores. In addition, four different quenching mechanisms for tetrazine-modified fluorophores are presented. 相似文献
10.
《无机化学与普通化学杂志》2018,644(11):512-517
Five energetic salts of 3,6‐bishydrazino‐1,2,4,5‐tetrazine (BHT), namely (BHT)2(NTO)3 ( 3 ), (BHT)(BTT) · 2H2O ( 4 ), (BHT)(DNP)2 ( 5 ), (BHT)(NATr)2 ( 6 ), and (BHT)(FOX‐7)2 ( 7 ), were synthesized and fully characterized by elemental analysis, FT‐IR, and mass spectra. The crystal structures of salts 3 and 4 were obtained and determined. Sensitivities towards outside stimuli and thermal behaviors of all the compounds were investigated, besides, thermodynamics of both 3 and 4 were calculated as well. The compounds 3 – 7 exhibit splendid thermal stabilities and satisfactory sensitivities simultaneously. Notably, unlike the previously known layered packing, compound 4 was found to adopt an unusual layered crystal packing with arch layers alternately arranged upward or downward. It may play an important role in contributing to its superior thermal stability (350 °C), providing an enlightening thinking to design new highly thermal stable energetic materials. 相似文献