62821-88-9Relevant articles and documents
A pyrazolylamine-phosphonate monoester chelator for the fac-[M(CO) 3]+ core (M = Re, 99mTc): Synthesis, coordination properties and biological assessment
Palma, Elisa,Oliveira, Bruno L.,Figueira, Flavio,Correia, Joao D. G.,Raposinho, Paula D.,Santos, Isabel
, p. 1176 - 1184 (2007)
Aiming to develop new strategies for the labeling of hydroxyl-containing biomolecules with the organometallic core fac-[99mTc(CO) 3]+, we have prepared a new model bifunctional chelator, L4 (ethyl hydrogen (2-{[2-(3,5-dimethyl-1H-pyrazol-l-yl)ethyl]amino}ethyl) phosphonate), combining a pyrazolyl-amine chelating group and a monophosphonate ethyl ester function (-P(O)OHOEt). The phosphonate group allows metal stabilization, and, simultaneously, can be considered as a potential attachment site for a biomolecule. Reaction of L4 with the precursor [ 99mTc(H2O)3(CO)3]+ gave the model radiocomplex [99mTc(CO)3(k3-L4)] (6a). This radiocomplex was identified by comparing its chromatographic profile with that of the corresponding Re analog (6) under the same conditions, also prepared and fully characterized by the usual analytical techniques. Radiocomplex 6a is moderately lipophilic (log Po/w = 1.07), presenting high stability in vitro without any measurable decomposition or ligand exchange, even in the presence of strong competing chelators such as histidine and cysteine (37°C, 24h). Biodistribution studies of the complex in CD-1 mice indicated a rapid blood clearance, and a rapid clearance from main organs, occurring primarily through the hepatobiliary pathway. Complex 6a presents also a high robustness in vivo, demonstrated by its resistance to metabolic degradation in blood, and intact excretion into the urine, after RP-HPLC analysis of blood and urine samples. Copyright
Copper (II) complexes with novel Schiff-based ligands: synthesis, crystal structure, thermal (TGA–DSC/FT-IR), spectroscopic (FT-IR, UV-Vis) and theoretical studies
Moreira, Jeniffer Meyer,Campos, Guilherme Fava,de Campos Pinto, Leandro Moreira,Martins, Gabriel Rodrigues,Tirloni, Bárbara,Schwalm, Cristiane Storck,de Carvalho, Cláudio Teodoro
, p. 4087 - 4098 (2021/05/10)
This study aimed to synthesize two novel Schiff-base ligands through the condensation between N-(2-aminoethyl)pyrazoles and 2-hydroxy-1-naphthaldehyde, which are: NaphPz ((E)-1-(((2-(1H-pyrazol-1-yl)ethyl)imino)methyl)naphthalen-2-ol)) and NaphDPz ((E)-1-(((2-(3,5-dimethyl-1H-pyrazol-1-yl)ethyl)imino)methyl)naphthalen-2-ol). These novel pyrazole-imines were synthesized, characterized and used as copper (II) ion complexing agents. Different synthetic routes have been adapted to obtain the [Cu(NaphPz)Cl], [Cu(NaphDPz)Cl] and [Cu(NaphPz)2] complexes in the solid state, the first two in the crystalline form and the latter as a powder. The minimum metal–ligand stoichiometry for the three complexes was defined by TGA–DSC thermoanalytical data and by single-crystal X-ray diffraction for the crystalline samples which belong to the P21/n space group. The products of the thermal decomposition of the material were also monitored by TGA–DSC/FT-IR in air and N2 atmospheres in order to suggest how thermal decomposition of the organic portion of the complex occurs. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations compared to experimental results (UV-Vis and FT-IR) show a high degree of correlation. From HOMO/LUMO orbitals, the main major charge distributions, responsible for the absorption bands of the complexes, were determined.
Synthesis of 1-(2-aminoethyl)pyrazoles under phase-transfer catalysis
Attaryan,Baltayan,Sagatelyan,Takmazyan
, p. 136 - 138 (2008/09/18)
Alkylation of pyrazoles with 2-chloroethylamine was performed under conditions of phasetransfer catalysis. Depending on the substrate acidity, the electrophilic substitution process may be accompanied by dehydrochlorination of the alkylating agent, so that 6 equiv of 2-chloroethylamine should be used in the alkylation of 3,5-dimethylpyrazole.
