Dextran Fluorescent Probes Containing Sulfadiazine and Rhodamine B Groups.

Fluorescent imaging has been expanded, as a non-invasive diagnostic modality for cancers, in recent years. Fluorescent probes in the near-infrared window can provide high sensitivity, resolution, and signal-to-noise ratio, without the use of ionizing radiation. Some fluorescent compounds with low molecular weight, such as rhodamine B (RhB) and indocyanine green (ICG), have been used in fluorescent imaging to improve imaging contrast and sensitivity; however, since these probes are excreted from the body quickly, they possess significant restrictions for imaging. To find a potential solution to this, this work investigated the synthesis and properties of novel macromolecular fluorescent compounds. Herein, water-soluble dextran fluorescent compounds (SD-Dextran-RhB) were prepared by the attachment of RhB and sulfadiazine (SD) derivatives to dextran carrier. These fluorescent compounds were then characterized through IR, 1H NMR, 13C NMR, UV, GPC, and other methods. Assays of their cellular uptake and cell cytotoxicity and fluorescent imaging were also performed. Through this study, it was found that SD-Dextran-RhB is sensitive to acidic conditions and possesses low cell cytotoxicities compared to normal 293 cells and HepG2 and HeLa tumor cells. Moreover, SD-Dextran-RhB demonstrated good fluorescent imaging in HepG2 and HeLa cells. Therefore, SD-Dextran-RhB is suitable to be potentially applied as a probe in the fluorescent imaging of tumors.

Auxiliary ligand-directed structural variation from 2D→3D polythreaded net to 3-fold interpenetrating 3D pillar-layered framework: syntheses, crystal structures and magnetic properties.

By auxiliary N-donor ligand-directed assembled, two entangled Co(II)-coordination nets have been constructed from 3,3',5,5'-azobenzenetetracarboxylic acid (H(4)abtc), which present a rare 2D→3D polythreading motif constructed from 2-fold (6,3) polymeric layers with thickness being 10.2 Šand a 3-fold interpenetrating pillar-layered framework based on linear trinuclear Co(II)-SBUs. In addition, two Co(II)-complexes both show an antiferromagnetic coupling by long organic spacers and H(2)O bridges, respectively.

4,4'-(Ethene-1,2-diyl)dipyridinium bis-[4-(2-carboxy-benzo-yl)benzoate].

In the crystal structure of the title compound, C(12)H(12)N(2) (2+)·2C(15)H(9)O(5) (-), the cation has site symmetry with the mid-point of C=C bond located on an inversion center. The two benzene rings of the anion are oriented at a dihedral angle 85.87 (6)°. In the crystal, inter-molecular O-H⋯O and N-H⋯O hydrogen bonds link the cations and anions into supra-molecular double chains, which are further connected into a three-dimensional network through inter-molecular C-H⋯O and π-π stacking between parallel pyridine rings [centroid-centroid distance = 3.4413 (12)Å] and between parallel benzene rings [centroid-centroid distance = 3.6116 (14)Å].

Aqua-bis(2-amino-1,3-thia-zole-4-acetato-κO,N)nickel(II).

In the crystal structure of the title compound, [Ni(C(5)H(5)N(2)O(2)S)(2)(H(2)O)], the Ni(II) cation is located on a twofold rotation axis and chelated by two 2-amino-1,3-thia-zole-4-acetate (ata) anions in the basal coordination plane; a water mol-ecule located on the same twofold rotation axis completes the distorted square-pyramidal coordination geometry. Inter-molecular O-H⋯O and N-H⋯O hydrogen bonding, as well as π-π stacking between parallel thia-zole rings [centroid-centroid distance 3.531 (8) Å], helps to stabilize the crystal structure.

Aqua-(2,2'-bipyrimidine-κN,N')(succin-ato-κO,O)copper(II) dihydrate.

In the crystal structure of the title compound, [Cu(C(4)H(4)O(4))(C(8)H(6)N(4))(H(2)O)]·2H(2)O, the Cu(II) atom is chelated by a 2,2'-bipyrimidine (bpm) ligand and a succinate anion in the basal plane; a water mol-ecule in the apical position completes the slightly distorted square-pyramidal coordination geometry. Another carboxyl-ate O atom from an adjacent complex is located in the opposite apical direction, with a Cu⋯O distance of 2.706 (3) Å, and is not considered as a bridging atom. Extensive O-H⋯O and O-H⋯N hydrogen bonding is present in the crystal structure.

catena-Poly[[(1,10-phenanthroline-κN,N')copper(I)]-µ-thiocyanato-κN:S-[(1,10-phenanthroline-κN,N')copper(I)]-µ-cyanido-κN:C].

In the title complex, [Cu(2)(CN)(NCS)(C(12)H(8)N(2))(2)], which was synthesized under hydro-thermal conditions, both Cu(I) atoms have a slightly distorted tetra-hedral geometry. They are coordinated by two N atoms of one 1,10-phenanthroline ligand, one bridging thio-cyanate anion and one bridging cyanide anion. In the crystal structure, infinite helical {Cu-CN-Cu-SCN}(n) chains are formed along [01].