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The discovery of novel tetrahydropyrrolo[1,2-c]pyrimidines derivatives from Bay41_4109 as hepatitis B virus (HBV) inhibitors is herein reported. The structure–activity relationship optimization led to one highly efficacious compound 28a (IC50 = 10 nM) with good PK profiles and the favorite L/P ratio. The hydrodynamic injection model in mice clearly demonstrated the efficacy of 28a against HBV replication.

The study of iron chelators as cancer chemotherapeutic agents is still in its infancy. Accordingly, there is a need to optimize new chelating molecules for iron chelation therapy and cancer treatment. Previous studies have demonstrated that the ligand tris(1-pyrazolyl) borohydride and its derivates were able to chelate ferrous iron, but very little research focused on their biological properties and applications in cancer treatment. So, in this study, several boron-pyrazole derivatives were chosen for the examination of their effects on the proliferation of human hepatocellular carcinoma (HCC) cell lines. The results suggested that potassium tris(4-methyl-1-pyrazolyl) borohydride (KTp(4-Me)) exhibited the most potent anti-tumor activities among the candidates. Hence, the antiproliferative activity and the iron chelating capacity of the iron chelator KTp(4-Me) in HCC cell lines HepG2 and Hep3B were characterized. KTp(4-Me) could disrupt cell iron uptake and affect signaling pathways of iron regulation in HCC cell lines and induced the expression of TfR1 and HIF-1α in a concentration-dependent manner, which was a typical cell response to iron deficiency. Moreover, KTp(4-Me) arrested cell cycle in S phase and induced cell apoptosis in both Hep3B and HepG2 cells. Overall, our results provide a promising starting point and the possibility of the future development and applications of KTp(4-Me) in HCC therapy.

Poly (N-ethyl-4-vinylpyridiniumbromide) (PEVP) was synthesized by the reaction between poly (4-vinylpyridine) (P4VP) and ethyl bromide, and polyelectrolyte complexes (PECs) based on PEVP and sodium carboxymethyl cellulose (CMCNa) were prepared in HCl aqueous solutions. The ionic complexation degrees (ICD) of PECs can be effectively controlled by tuning either quaternization degree (QD) of PEVP polycation or carboxylate group (–COO–) content on CMCNa polyanion, which was characterized by elemental analysis (EA) and Fourier transform infrared (FT-IR). The dilute solution viscosity behavior of PECs was investigated by Ubbelohde viscometer. The hydrophilicity and surface morphologies of polyelectrolyte complex membranes (PECMs) were examined by contact angle meter and field emission scanning electron microscopy (FESEM), respectively. The PECMs were subjected to dehydration of ethanol and showed very high separation performance. Interestingly, the permeation flux of PECMs increased while water content in permeate decreased with increasing ICD. The performance was discussed in terms of the unique structural characteristics of PEVP, PECs and PECMs.

Soluble polyelectrolyte complexes (PECs) between chitosan (CS) and sodium carboxymethyl cellulose (CMCNa) were synthesized in aqueous hydrochloric acid (HCl) and obtained in their solid form. FT-IR, elemental analysis (EA), thermal gravity analysis (TGA), wide-angle X-ray diffraction (WAXD), and viscometry were used to characterize the chemical structure, composition, thermal stability, crystallinity and solution property of PECs, respectively. These PECs could be dissolved in aqueous NaOH and their homogeneous polyelectrolyte complex membranes (HPECMs) were made by solution casting method. Both the surface morphology of HPECMs and the morphology of single PEC aggregate were examined by field emission scanning electron microscope (FESEM), and atomic force microscopy (AFM). Effects of the water content in aqueous ethanol and temperature on the swelling behavior and pervaporation dehydration of HPECM were examined. A good performance of J = 1.14 kg/m2 h, α = 1062 was obtained with HPECM0.25 in dehydrating 10 wt.% water–ethanol at 70 °C. The swelling behavior and pervaporation performance were interpreted in terms of structure characteristics of both PECs and HPECMs.

Polyelectrolyte complexes (PECs) between poly(diallyldimethylammonium chloride) (PDDA) and sodium carboxymethyl cellulose (CMCNa) with four ionic complexation degrees (ICD) were synthesized and their homogeneous polyelectrolyte complex membranes (HPECMs) were fabricated. Elemental analysis and FT-IR were used to determine the composition and chemical structure of PECs. Thermogravimetric analysis (TGA), wide-angle X-ray diffraction (WAXD) and viscometry were used to characterize the thermal stability, crystallinity and solution properties of PECs, respectively. Field emission scanning electron microscope (FESEM) was used to examine the surface morphology of HPECMs, which were subjected to the pervaporation dehydration of isopropanol. Effects of membrane fabrication methods, cycling of feed temperature and ICD of PECs on pervaporation performance of HPECMs are discussed. Meanwhile, HPECMs were also subjected to dehydration of three other organics and showed very good performance. All these performances are explained in terms of the unique structural characteristics of PECs and HPECMs.

Polyethylenimine/poly(acrylic acid sodium salt) (PEI/PAA) ultrathin polyelectrolyte multilayer membranes were fabricated by an electric field enhanced method and were used for isopropanol/water pervaporation. Surface properties of the electric field enhanced multilayer polyelectrolyte membranes (EPEMs) prepared under different conditions were investigated by atomic force microscopy (AFM) and contact angle (CA) measurements. It was found that surface properties (roughness and hydrophilicity) of EPEMs strongly depend on the direction of the electric field, dipping time, applied voltage, number of bilayers, which, in turn, affect their pervaporation performance. The (PEI/PAA)4PEI EPEMs fabricated with a dipping time of 15 min and an applied voltage of 5 V for separating 10 wt% water–isopropanol mixtures exhibited high separation factor and large flux. Meanwhile, the performance of the EPEMs displays good storage stability within 60 days.