A 3-D metal-organic framework constructed with manganese(ΙΙ), 4,4'-oxybis(benzoic acid) and 2,2'-biphenyl: synthesis, crystal structure and photoelectric property characterization.

Assembly of 4,4'-oxybis(benzoic acid) (H(2)L) with manganese chloride in the presence of 2,2'-biphenyl (2,2'-bpy) affords a new coordination polymer [Mn(3)L(3)(2,2'-bpy)(2)](n) (1), in which the [MnL(2)]n layers are extended by L bridges resulting in a three-dimensional (3-D) coordination framework. The network structure of 1 has unusual (2,6)-connectivity and represents a new type of (8(12) · 12(3))(8)(3) topology. These identical and complementary networks are entangled to generate a self-penetrating supramolecular lattice. Moreover, the fluorescence spectrum of 1 exhibits fluorescent emission in the solution of methanol at room temperature. Electrochemical investigation illustrates the electrochemical properties of the title compound. The structure (C(62)H(40)Mn(3)N(4)O(15))(n) is monoclinic with a = 14.2304(18), b = 17.019(2), c = 25.805(3) Å, α = γ = 90, ß = 92.932(2)° and space group C2/c.

Bis{µ-2-[3-carboxyl-atometh-yl-4-(phenyl-sulfan-yl)phen-yl]propano-ato-κ(4)O,O':O'',O'''}bis-[(2,2'-bipyridine-κ(2)N,N')cadmium].

In the title complex, [Cd(2)(C(17)H(14)O(4)S)(2)(C(10)H(8)N(2))(2)], which was hydro-thermally synthesized, the Cd(II) cation is hexa-coordinated in a distorted octa-hedral geometry by two N atoms from a 2,2'-bipyridine ligand and by four O atoms from two different 2-[3-carboxyl-atometh-yl-4-(phenyl-sulfan-yl)phen-yl]propano-ate ligands, forming a cyclic dimetallic complex.

Dichlorido(ethanol-κO)[2-(1,3-thia-zol-4-yl-κN)-1H-benzimidazole-κN(3)]copper(II).

In the title complex, [CuCl(2)(C(10)H(7)N(3)S)(C(2)H(5)OH)], the Cu(II) ion is five-coordinated in a distorted square-pyramidal geometry by two N atoms from a 2-(1,3-thia-zol-4-yl)-1H-benzimidazole ligand, one O atom from an ethanol mol-ecule and two Cl atoms. In the crystal, O-H⋯Cl and N-H⋯Cl hydrogen bonds link the complex mol-ecules into a layer parallel to (100). π-π inter-actions between the thia-zole rings are observed [centroid-centroid distance = 3.749 (3) Å].

Ab initio theoretical study of the interactions between CFCl3 and SO2.

Ab initio calculations have been performed on complexes of CFCl3 with SO2. Ten complexes were found stable, the interaction energies that reflect their stability were corrected by the basis set superposition error and the correction of zero-point energy. The natures of these interactions were investigated by the analysis of natural bond orbital and the atoms in molecules. The results from theoretical calculation indicated that there were the interactions of Cl...O, F...O, Cl...S and F...S between CFCl3 and SO2, furthermore, the non-covalent bonds of Cl...O and Cl...S were the major interaction forces, which provided some data and information for studying the environment problem such as greenhouse effect relevant to CFCl3 and SO2.

Improving the Solubility and Bioavailability of Pemafibrate via a New Polymorph Form II.

Pemafibrate is a new generation of anti-hyperlipidemia drugs. However, its poor solubility in water (0.410 mg/mL at 25 °C) has limited its oral bioavailability. In this study, we aimed to improve the solubility and consequently the oral bioavailability of pemafibrate via a new polymorph. A new polymorph Form II was successfully obtained by controlling the crystallization temperature and characterized by multiple analysis methods. The thermodynamic properties of Form I and Form II are almost the same, the melting points of crystal Form I [differential scanning calorimetry (DSC) onset: 97.5 °C, melting entropy: -76 J/g] and crystal Form II (DSC onset: 96.6 °C, melting entropy: -80 J/g) are very close, and the crystallinity of both is very high. In pure water, Form II is about 1.9 times that of Form I in terms of the intrinsic dissolution rate (IDR) and powder solubility. In medium, the IDR characterization was performed in a pH 6.8 buffer. The solubility of this Form II in 0.1 M HCl (pH 1.0) and phosphate buffers (pH 6.8) was investigated, and the results showed that the solubility of Form II was 2.1 and 2.0 times that of Form I, respectively. The crystal structure of Form II shows that the hydrophilic carboxyl groups of the compound are arranged outside the unit cell, which may be the reason for the increased solubility. We also studied the pharmacokinetics of beagle dogs. The mean AUC0-24h of Form II is about 2.6 times that of Form I, indicating that the solubility and bioavailability of pemafibrate can indeed be improved by forming the new polymorph Form II. It may become an ideal solid form of active pharmaceutically ingredient suitable for pharmaceutical preparations, and it can be further studied in the later period.

Improving the solubility and bioavailability of anti-hepatitis B drug PEC via PEC-fumaric acid cocrystal.

PEC is a new generation of phosphamide ester anti-hepatitis B virus drug. It is a prodrug of tenofovir and can be rapidly metabolized to tenofovir. However, its poor solubility in water (0.219 mg mL-1 at 25 °C) has limited its oral bioavailability. In this study, we aimed to improve the solubility and consequently the oral bioavailability of PEC via a cocrystal. A cocrystal of PEC with fumaric acid (FUA) (PEC-FUA, 1 : 1) was successfully obtained and characterized. The crystal structure of this cocrystal was tested using a single crystal X-ray diffraction method. The intrinsic dissolution rate (IDR) characterization was performed in a pH 6.8 buffer. The solubility of this cocrystal in 0.1 M HCl (pH 1.0) and pH 6.8 phosphate buffers was investigated, and the results showed that the solubility of the cocrystal was 3.8 and 4.0 times that of free PEC, respectively. We also studied the pharmacokinetics of beagle dogs. The mean AUC0-24 h of the cocrystal is about 4.2 times that of free PEC, indicating that the solubility and bioavailability of PEC can indeed be improved by forming the cocrystal. It may become an ideal solid form of an active pharmaceutical ingredient suitable for pharmaceutical preparations, and it can be further studied later.

[Evaluation of Performance of an Aminated Rosin-based Resin for Adsorption of Norfloxacin from Aqueous Solutions].

An aminated rosin-based resin (ARBR) was synthesized as a novel environmentally-friendly adsorbent for removal of Norfloxacin (NOR) from aqueous solutions. Its features were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and surface area measurements (BET). The effects of resin dosage, pH, and ionic strength on the ARBR adsorption properties of NOR were investigated by batch experiments. Results showed that the NOR adsorption amounts increased with pH in the range from 2.0 to 6.0, but decreased at higher pH (8-10). The adsorption process of NOR followed a pseudo-second rate model and could be fitted to the Langmuir isotherm, with calculated maximum monolayer adsorption capacity of 30.29 mg·g-1 at pH 6.0 and 20℃. Thermodynamic calculations showed that the adsorption of NOR was a spontaneous and endothermic process and could be attributed to a combination of electrostatic interactions and hydrogen bonding. Furthermore, the adsorbed NOR on ARBR could be efficiently desorbed by 0.1 mol·L-1 HCl to regenerate the resin. After five adsorption-desorption recycles, ARBR had a stable adsorption performance and could be recycled. The adsorption performance is better than that of various commercial resins, and these research results contribute to the development of applications of rosin derivatives and their utilization in the environmental control of micro pollutants.