ABSTRACT
Aim: Obtain radioimages of amyloid-ß fibers using 99mTc-complexes. Methodology: Tridentate thiosemicarbazone and thiocarbonohydrazone ligands containing fragments (stilbene, azobenzene, benzothiazole or benzoxazole) with affinity for amyloid-ß fibers and its Re(I) complexes have been prepared. The molecular structures of several ligands and complexes were determined by x-ray diffraction. Binding affinity studies toward Aß1-42 fibers were performed for the ligands and Re(I) complexes. The ability of formation of some 99mTc(I) complexes, their biodistribution and in vivo stability have been established. Results & conclusion: Complexes of stilbene and benzothiazole thiosemicarbazonates show similar affinity for amyloid-ß fibers to the free ligand. These 99mTc complexes present a reasonable in vivo stability and a low capability to cross the blood-brain barrier although not sufficient to brain amyloid imaging.
Subject(s)
Amyloid beta-Peptides/chemistry , Brain/diagnostic imaging , Radiopharmaceuticals/chemistry , Thiosemicarbazones/chemistry , Amyloid beta-Peptides/metabolism , Brain/metabolism , Humans , Ligands , Molecular Structure , Radiopharmaceuticals/analysis , Radiopharmaceuticals/chemical synthesis , Thiosemicarbazones/analysis , Thiosemicarbazones/chemical synthesisABSTRACT
A series of new zinc compounds has been prepared easily under mild synthetic conditions with the drug ibuprofen incorporated as a ligand to form different coordination polymers. The host materials have a high drug content and exhibit high stability, low cytotoxicity, good biodegradability and high biocompatibility. The ion exchange mechanism involved in the ibuprofen release process and the pH-controlled drug release have been studied.
Subject(s)
Ibuprofen/chemistry , Organometallic Compounds/pharmacology , Polymers/pharmacology , Zinc/pharmacology , Cell Proliferation/drug effects , Crystallography, X-Ray , Dose-Response Relationship, Drug , Drug Stability , Humans , Hydrogen-Ion Concentration , Models, Molecular , Organometallic Compounds/chemical synthesis , Organometallic Compounds/chemistry , Particle Size , Polymers/chemical synthesis , Polymers/chemistry , Structure-Activity Relationship , Surface Properties , Zinc/chemistryABSTRACT
Materials based on the cationic copper(II) hexanuclear 18-membered metallacrown [18-MCCuII-N(2ph)-6](6+) (2phH=2-piconyl hydrazide) and tetrafluoroborate, perchlorate, nitrate, sulfate, and perrhenate anions were prepared by an easy method in aqueous medium. Single-crystal X-ray characterization of six members of this new family of complexes showed that the anions are attached to the metallacrown by direct coordination to a copper cation or by hydrogen-bonding interaction with the center of the hexamer. The stable cationic nature of the complexes and their ability to bind different anions allows them to adsorb and immobilize environmentally relevant anions such as MO4(-) (M=Tc, Re). The MO4(-) trapping capacities suggest that these materials would be useful in the treatment of oxoanionic contaminants in water.
ABSTRACT
The structure of the title compound, C10H11N3OS, comprises an approximately planar mol-ecule, with the r.m.s. deviation for the 15 non-H atoms being 0.089â Å. The conformation about the imine bond is E and an intra-molecular N-Hâ¯N hydrogen bond is evident. Mol-ecules are linked into a supra-molecular chain along the b axis by N-Hâ¯S hydrogen bonds.
ABSTRACT
The asymmetric unit of the title compound, C9H9N3OS, contains two approximately planar mol-ecules (r.m.s. deviations for 14 non-H atoms = 0.094 and 0.045â Å), with different conformations. In one of them, the C=O group is syn to the S atom and in the other it is anti. Each mol-ecule features an intra-molecular N-Hâ¯N hydrogen bond, which generates an S(5) ring. In the crystal, mol-ecules are linked by N-Hâ¯O and N-Hâ¯S hydrogen bonds, generating discrete networks; the syn mol-ecules form [010] chains and the anti mol-ecules form (100) sheets.
