Crystal structure of (S)-5-chloro-N-({2-oxo-3-[4-(3-oxomorpholin-4-yl)phen-yl]oxazolidin-5-yl}meth-yl)thio-phene-2-carboxamide.

The asymmetric unit of the crystal of the title compound (common name rivaroxaban), C19H18ClN3O5, contains two rivaroxaban mol-ecules with different conformations; the C-C-N-C torsion angles between the oxazolidine and thio-phene rings are -171.1 (7) and -106.8 (9)° in the two independent mol-ecules. In the crystal, classical N-H⋯O hydrogen bonds and weak C-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional supra-molecular architecture.

Crystal structure of canagliflozin hemihydrate.

There are two canagliflozin mol-ecules (A and B) and one water mol-ecule in the asymmetric unit of the title compound, C24H25FO5S·0.5H2O [systematic name: (2S,3R,4R,5S,6R)-2-(3-{[5-(4-fluoro-phen-yl)thio-phen-2-yl]meth-yl}-4-methylphen-yl)-6-(hy-droxy-meth-yl)-3,4,5,6-tetra-hydro-2H-pyran-3,4,5-triol hemihydrate]. The dihedral angles between the methyl-benzene and thio-phene rings are 115.7 (4) and 111.7 (4)°, while the dihedral angles between the fluoro-benzene and thio-phene rings are 24.2 (6) and 20.5 (9)° in mol-ecules A and B, respectively. The hydro-pyran ring exhibits a chair conformation in both canagliflozin mol-ecules. In the crystal, the canagliflozin mol-ecules and lattice water mol-ecules are connected via O-H⋯O hydrogen bonds into a three-dimensional supra-molecular architecture.

Crystal structure of febuxostat-acetic acid (1/1).

The asymmetric unit of the title compound [systematic name: 2-(3-cyano-4-iso-butyl-oxyphen-yl)-4-methyl-thia-zole-5-carb-oxy-lic acid-acetic acid (1/1)], C16H16N2O3S·CH3COOH, contains a febuxostat mol-ecule and an acetic acid mol-ecule. In the febuxostat mol-ecule, the thia-zole ring is nearly coplanar with the benzene ring [dihedral angle = 3.24 (2)°]. In the crystal, the febuxostat and acetic acid mol-ecules are linked by O-H⋯O, O-H⋯N hydrogen bonds and weak C-H⋯O hydrogen bonds, forming supra-molecular chains propagating along the b-axis direction. π-π stacking is observed between nearly parallel thia-zole and benzene rings of adjacent mol-ecules; the centroid-to-centroid distances are 3.8064 (17) and 3.9296 (17) Å.

Cyclodextrin-based host-guest supramolecular nanoparticles for delivery: from design to applications.

CONSPECTUS: Efficient assembly in host-guest interactions is crucial to supramolecular nanotechnology. Cyclodextrins (CDs), which possess a hydrophilic exterior surface and hydrophobic interior cavity on the truncated cone, improve the biocompatibility of nanodelivery systems, and hence, supramolecular approaches utilizing CDs can improve and expand the design and applications of functional delivery systems. Owing to good inclusion ability, αCD and ßCD are commonly used in the design and construction of supramolecular structures. In this Account, we describe the design strategies to adopt CDs in host-guest delivery systems. Modification of CDs with polymers is popular in current research due to the potential benefits rendered by cationic protection and improved capability. While the process has only minor influence on the host characteristics of the CD cavity, the interaction between the CD and the guest moiety imparts new attributes to the nanosystems with guest-decorated functional groups such as adamantyl poly(ethylene glycol) (PEG) for coating protection, hybrid guests for conformational flexibility, and adamantyl prodrugs for drug delivery. Some specific agents form inclusion complexes with the polymerized ßCDs directly and core-shell nanoparticles with hydrophobic cores and are usually created to carry insoluble drugs while the hydrophilic shells offer protection. These unique designs provide the means to practically adapt special characteristics for additional functions or co-delivery. In order to be accepted clinically, delivery systems need to possess extra functions such as controlled particle size, biodegradability, controlled release, and targeted delivery to overcome the hurdles in delivery. These features can be added to biomaterials by self-assembly of functional groups facilitated by the host-guest interactions. Size control by hybridization of switchable polymer compartments in supramolecular structures contributes to the biodistribution utility and biodegradability by incorporating the moieties with hydrolyzable connections and enhancing intracellular degradation and clearance. Controlled release by application of responsive structures like molecular gatings eased by the host-guest interaction can be triggered by the tumor microenvironment at extreme pH and temperature or by external stimuli such as light. Along with the binding selectivity and controlled release, the host-guest nanoparticles show enhanced efficacy in delivery especially to tumors. Recent developments in supramolecular co-delivery systems are described in this Account. Nanoparticles can be designed to carry adamantyl prodrugs and therapeutic nucleotides to tumors so that the released drugs and gene expression synergistically inhibit malignant tissue growth. Optimization of nanoparticle delivery systems by multifunctional transitions yields better biocompatibility and controlled response, and such novel designs will expedite in vivo applications. Hence, multifunctional CD-based host-guest supramolecular nanoparticles with co-delivery ability are expected to have many potential clinical applications.

Macrophage mannose receptor-specific gene delivery vehicle for macrophage engineering.

Macrophages are the most plastic cells in the hematopoietic system and they exhibit great functional diversity. They have been extensively applied in anti-inflammatory, anti-fibrotic and anti-cancer therapies. However, the application of macrophages is limited by the efficiency of their engineering. The macrophage mannose receptor (MMR, CD206), a C-type lectin receptor, is ubiquitously expressed on macrophages and has a high affinity for mannose oligosaccharides. In the present study, we developed a novel non-viral vehicle with specific affinity for MMR. Mannan was cationized with spermine at a grafted ratio of ∼12% to deliver DNA and was characterized as a stable system for delivery. This spermine-mannan (SM)-based delivery system was evaluated as a biocompatible vehicle with superior transfection efficiency on murine macrophages, up to 28.5-fold higher than spermine-pullulan, 11.5-fold higher than polyethylenimine and 3.0-fold higher than Lipofectamine™ 2000. We confirmed that the SM-based delivery system for macrophages transfection was MMR-specific and we described the intracellular transport of the delivery system. To our knowledge, this is the first study using SM to demonstrate a mannose receptor-specific gene delivery system, thereby highlighting the potential of a novel specific non-viral delivery vehicle for macrophage engineering.

Efficient poly(N-3-hydroxypropyl)aspartamide-based carriers via ATRP for gene delivery.

High-molecular-weight comb-shaped cationic copolymers have been of interest and importance as nonviral gene delivery carriers. Poly(DL-aspartamide)-based biomaterials with good degradability and excellent biocompatibility could be used as the potential backbones of gene vectors. In this work, atom transfer radical polymerization (ATRP) was proposed to prepare the biocleavable and biodegradable comb-shaped poly(N-3-hydroxypropyl)aspartamide (PHPA)-based gene carriers. The bioreducible ATRP initiation sites were first introduced onto PHPA backbones. Then, the well-defined comb-shaped vectors (SS-PHPDs) consisting of degradable PHPD backbones and disulfide-linked cationic P(DMAEMA) side chains were produced for gene delivery. The P(DMAEMA) side chains were readily cleavable from the backbones under reducible conditions. The degradability of PHPA backbones would benefit the final removal of the gene carriers from the body.

[Synthesis of a supermolecular nanoparticle γ-hy-PC/Ada-Dox and its antitumor activity].

OBJECTIVE: To synthesize a (2-Hydroxypropyl)-γ-cyclodextrin-polyethylenimine/adamantane-conjugated doxorubicin (γ-hy-PC/Ada-Dox) based supramolecular nanoparticle with host-guest interaction and to identify its physicochemical characterizations and antitumor effect. METHODS: A novel non-viral gene delivery vector γ-hy-PC/Ada-Dox was synthesized based on host-guest interaction. 1H-NMR, NOESY, UV-Vis, XRD and TGA were used to confirm the structure of the vector. The DNA condensing ability of complexes was investigated by particle size, zeta potential and gel retardation assay. Cytotoxicity of complexes was determined by MTT assay in BEL-7402 and SMMC-7721 cells. Cell wound healing assay was performed in HEK293 and BEL-7404 cells. The transfection efficiency was investigated in HEK293 cells. H/E staining and cell uptake assay was performed in BEL-7402 cells. RESULTS: The structure of γ-hy-PC/Ada-Dox was characterized by 1H-NMR, NOESY, UV-Vis, XRD, TGA. The drug loading was 0.5% and 5.5%. Gel retardation assay showed that γ-hy-PC was able to completely condense DNA at N/P ratio of 2; 0.5% and 5.5% γ-hy-PC/Ada-Dox was able to completely condense DNA at N/P ratio of 3 and 4,respectively. The cytotoxicity of polymers was lower than that of PEI25KDa. The transfection efficiency of γ-hy-PC was higher than that of γ-hy-PC/Ada-Dox at N/P ratio of 30 in HEK293 cells; and the transfection efficiency was decreasing when Ada-Dox loading was increasing. Cell uptake assay showed that γ-hy-PC/Ada-Dox was able to carry drug and FAM-siRNA into cells. CONCLUSION: The novel vector γ-hy-PC/Ada-Dox has been developed successfully, which has certain transfection efficiency and antitumor activity.

[Anticancer effect of triptolide-polyethylenimine-cyclodextrin in vitro].

OBJECTIVE: To develop a drug delivery system triptolide-polyethylenimine-cyclodextrin and to evaluate its anticancer activity in vitro. METHODS: Triptolide was conjugated to polyethylenimine-cyclodextrin by N, N'-carbonyldiimidazole to form triptolide-polyethylenimine-cyclodextrin. (1)H-NMR, FT-IR and XRD were used to confirm its structure. The anticancer effect of the polymer was assessed by MTT assay, erasion trace test and hematoxylin-eosin staining. The potential to condense siRNA and to delivery siRNA into cytoplasm was demonstrated by gel retardation assay, zeta-potential determination and fluorescence staining. RESULTS: Triptolide was successfully conjugated to polyethylenimine-cyclodextrin and the conjugation rate of triptolide was 10% (w/w). siRNA was effectively condensed by the polymer at the N/P ratio of 5, and its particle size was 300 ±15 nm and zeta potential was 8 ±2.5 mV. MTT assay, erasion trace test and hematoxylin-eosin staining revealed that triptolide-polyethylenimine-cyclodextrin had anticancer effect and low cytotoxicity to normal cells. The polymer was able to deliver siRNA to the cytoplasm effectively as demonstrated by fluorescence staining. CONCLUSION: Triptolide-polyethylenimine-cyclodextrin is able to inhibit the growth and migration of cancer cells in vitro and to carry siRNA into cells effectively. It is potential to be used as a novel prodrug for co-delivery of gene and drug in cancer treatment.

[Characteristics of cationic polymers PEI-CyD, PEI-PHPA, PEE-PHPA and PEI25kD in vitro and in vivo].

OBJECTIVE: To study the characteristics of cationic polymers polyethylenimine-ß-cyclodextrin (PEI-CyD), polyethylenimine-poly-(3-hydroxypropyl)-aspartamide (PEI-PHPA), N,N-Dimethyldipropylenetriamine-Bis(3-aminopropyl)amine-aspartamide (PEE-PHPA) in vitro and in vivo. METHODS: PEI-PHPA, PEI-CyD and PEE-PHPA were synthesized and the chemistry structure of PEI-PHPA, PEI-CyD and PEE-PHPA was confirmed by (1)H-NMR. The particle size and zeta potential of these polymers were measured, and capacity of plasmid DNA condensation was tested. The inhibition of COS-7, A549, HEK293 and C6 cells was measured by MTT assay. The transfection efficiency was determined in HEK293 cell lines. The toxicity, tissue distribution and transfection efficiency of cationic polymers were tested in vivo. RESULTS: When the N/P of polymers/DNA at 30, the particle sizes were close 250 nm and the zeta-potential were near 35 mv. They were able to condense DNA at N/P ratio < 5. The MTT assay showed that the IC(50) of PEE-PHPA was 21.5, 20.2, 7.30 and 37.1 µg/ml, and that of PEI25kD was 15.8, 18.3, 11.4 and 36.7 µg/ml in C6, COS-7, A549 and HEK293cell lines, respectively. The cell viability of PEI-CyD and PEI-PHPA in above cell lines was over 60%. They had high transfection efficiency in HEK293 cell lines. The LD(50) of PEI25Kd, PEI-CyD, PEI-PHPA and PEE-PHPA in vivo was 19.50, 100.4, 521.2 and 630.0, respectively by intraperitoneal (ip) injection. The contractions of these polymers were higher in kidney than in other organs and tissues.PEE-PHPA had slight effect on kidney and liver function. CONCLUSION: PEE and PEI25kD have higher transfection efficiency and higher toxicity; while PC and PHPA-PEI have lower toxicity and higher transfection efficiency to be used as non-viral gene vector.

[Modified montmorillonite as multifunction gene and drug delivery system].

OBJECTIVE: To develop polyethylenimine-Doxorubicin-montmorillonite (PEI-Dox-MTT) as a novel multifunction delivery system. METHODS: Dox was intercalated into montmorillonite, PEI covered to the surface of Dox/MMT to make the nano-particle. XRD, FT-IR and TGA were used to confirm chemical property of the nano-particle. SEM was used to observe the morphology. The capability of drug release was investigated by PBS buffer solution (pH 7.4). The DNA binding ability of nano-particle was detected by gel electrophoresis retardation assay. The cell viability in COS-7 and SKOV3 cell lines was tested using MTT assay. The gastric mucosa protection was evaluated in vitro. RESULTS: XRD image showed that Dox was intercalated into montmorillonite, inter space of which increased to 31.3Å; the FT-IR spectra showed the vibration bands of PEI at 1 560 cm(-1) and 2 850 cm(-1), the vibration band of Dox at 1 350 cm(-1). Size analysis and SEM revealed that the size of nano-particle was 600 nm, and the zeta-potential was 30 mV. Drug release experiment explored that the nano-particle stably released drug in range of 6 X10(-4) ≊ 8 X10(-4) mg/ml within 72 h. MTT assay showed that the cell viability was over 80% in experiment condition in COS-7 and SKOV3 cell lines. 0.3 mg PEI-MMT nano-particle was able to protect gastric mucosa from alcohol. CONCLUSION: Multifunction system of PEI/Dox/MMT has been prepared successfully.

[Preparation and characterization of Forms A and B of benazepril hydrochloride].

OBJECTIVE: To prepare Form A and Form B of benazepril hydrochloride and to compare the differences in spectrums, thermodynamics and crystal structure between two polymorphic forms. METHODS: Form A and Form B of benazepril hydrochloride were characterized by Fourier transform infrared spectroscopy (IR), thermal gravimetric analysis (TG), differential scanning calorimetry (DSC), powder x-ray diffraction (PXRD) and single crystal x-ray diffraction (SCXRD). RESULTS: Preparation method, crystal structure and polymorphic stability of Form A and Form B of benazepril hydrochloride were obtained. Based on the analysis of crystal structure of both polymorphs, Form A belonged to monoclone space group P2(1) with a=7.8655(4)Å, b= 11.7700(6)Å, c= 13.5560(7)Å, ß= 102.9470(10)°, V=1223.07 (11)Å(3) and Z=2, while Form B belonged to orthorhombic space group P212121, with a=7.9353(8)Å, b=11.6654(11)Å, c=26.6453(16)Å, V=2466.5(4)Å(3) and Z=4. From the DSC and XRD results, Form B of benazepril hydrochloride could be transformed into Form A after heating treatment. CONCLUSION: Form A and Form B of benazepril hydrochloride are both anhydrous and displayed different polymorphs due to different molecular configuration. Furthermore, Form A exhibits more stable than Form B at high temperatures.

Mesenchymal stem cells as a novel carrier for targeted delivery of gene in cancer therapy based on nonviral transfection.

The success of gene therapy relies largely on an effective targeted gene delivery system. Till recently, more and more targeted delivery carriers, such as liposome, nanoparticles, microbubbles, etc., have been developed. However, the clinical applications of these systems were limited for their several disadvantages. Therefore, design and development of novel drug/gene delivery vehicles became a hot topic. Cell-based delivery systems are emerging as an alternative for the targeted delivery system as we described previously. Mesenchymal stem cells (MSCs) are an attractive cell therapy carrier for the delivery of therapeutic agents into tumor sites mainly for their tumor-targeting capacities. In the present study, a nonviral vector, PEI(600)-Cyd, prepared by linking low molecular weight polyethylenimine (PEI) and ß-cyclodextrin (ß-CD), was used to introduce the therapeutical gene, tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), to MSCs. Meanwhile, the characterization, transfection efficiency, cytotoxicity, cellular internalization, and its mechanism of this nonviral vector were evaluated. The in vitro expression of TRAIL from MSCs-TRAIL was demonstrated by both enzyme-linked immunosorbent assay and Western blot analysis. The lung tumor homing ability of MSCs was further confirmed by the in vitro and in vivo model. Moreover, the therapeutic effects as well as the safety of MSCs-TRAIL on lung metastases bearing C57BL/6 mice and normal C57BL/6 mice were also demonstrated. Our results supported both the effectiveness of nonviral vectors in transferring the therapeutic gene to MSCs and the feasibility of using MSCs as a targeted gene delivery carrier, indicating that MSCs could be a promising tumor target delivery vehicle in cancer gene therapy based on nonviral gene recombination.

Gene-carried hepatoma targeting complex induced high gene transfection efficiency with low toxicity and significant antitumor activity.

BACKGROUND: The success of gene transfection is largely dependent on the development of a vehicle or vector that can efficiently deliver a gene to cells with minimal toxicity. METHODS: A liver cancer-targeted specific peptide (FQHPSF sequence) was successfully synthesized and linked with chitosan-linked polyethylenimine (CP) to form a new targeted gene delivery vector called CPT (CP/peptide). The structure of CPT was confirmed by (1)H nuclear magnetic resonance spectroscopy and ultraviolet spectrophotometry. The particle size of CPT/ DNA complexes was measured using laser diffraction spectrometry and the cytotoxicity of the copolymer was evaluated by methylthiazol tetrazolium method. The transfection efficiency evaluation of the CP copolymer was performed using luciferase activity assay. Cellular internalization of the CP/DNA complex was observed under confocal laser scanning microscopy. The targeting specificity of the polymer coupled to peptide was measured by competitive inhibition transfection study. The liver targeting specificity of the CPT copolymer in vivo was demonstrated by combining the copolymer with a therapeutic gene, interleukin-12, and assessed by its abilities in suppressing the growth of ascites tumor in mouse model. RESULTS: The results showed that the liver cancer-targeted specific peptide was successfully synthesized and linked with CP to form a new targeted gene delivery vector called CPT. The composition of CPT was confirmed and the vector showed low cytotoxicity and strong targeting specificity to liver tumors in vitro. The in vivo study results showed that interleukin-12 delivered by the new gene vector CPT/DNA significantly enhanced the antitumor effect on ascites tumor-bearing imprinting control region mice as compared with polyethylenimine (25 kDa), CP, and other controls, which further demonstrate the targeting specificity of the new synthesized polymer. CONCLUSION: The synthesized CPT copolymer was proven to be an effective liver cancer-targeted vector for therapeutic gene delivery, which could be a potential candidate for targeted cancer gene therapy.

In vivo treatment of tumors using host-guest conjugated nanoparticles functionalized with doxorubicin and therapeutic gene pTRAIL.

The combination of gene therapy and chemotherapy may increase the therapeutic efficacy in the treatment of patients. In this work, the anti-cancer drug Dox and therapeutic gene pTRAIL-loaded host-guest co-delivery system was assayed for the possibility of in vivo synergistically treating tumors. The introduced Dox could act as an auxiliary component to human tumor necrosis factor-related apoptosis-inducing ligand-encoding plasmid gene pTRAIL. Such delivery system possessed the good ability of in vivo retention of chemotherapeutic drugs, achieved good therapeutic effects in the inhibition of tumor growth and significantly prolonged the survival time of tumor-bearing mice. With the efficient ability to co-deliver drug and gene, such host-guest assembly should have great potential applications in cancer therapy.

Gene-carried chitosan-linked polyethylenimine induced high gene transfection efficiency on dendritic cells.

A dendritic cell (DC) networking system has become an attractive approach in cancer immunotherapy. Successful DC gene engineering depends on the development of transgene vectors. A cationic polymer, chitosan-linked polyethylenimine (PEI) (CP), possessing the advantages of both PEI and chitosan, has been applied in nonviral transfection of DCs. Physicochemical evaluation showed that CP/DNA complexes could form cationic nanoparticles. Compared with DCs transfected with commercial reagent, Lipofectamine2000, it showed higher transfection efficiency and lower cytotoxicity when DCs were transfected with CP/DNA complexes. A nuclear trafficking observation of CP/DNA complexes by a confocal laser scanning microscope further revealed that the CP could help DNA enter into the cytoplasm and finally into the nucleus of a DC. Finally, vaccination of DCs transfected with CP/DNA encoding gp100 slightly improved resistance to the B16BL6 melanoma challenge. This is the first report that CP polymer is used as a nonviral vector for DC gene delivery and DC vaccine. Essentially, these results might be helpful to design a promising nonviral vector for DC gene delivery.

Bupropion hydro-bromide propanol hemisolvate.

The title compound {systematic name: N-[1-(3-chloro-phen-yl)-1-oxopropan-2-yl]-tert-butanaminium bromide propanol hemisolvate}, C(13)H(19)ClNO(+)·Br(-)·0.5C(3)H(8)O, crystallizes with two independent bupropion hydro-bromide ion pairs and a solvent 1-propanol mol-ecule in the asymmetric unit. In both mol-ecules, the expected proton transfer from HBr to the amino group of the bupropion mol-ecule is observed, and intra- and inter-molecular N-H⋯Br hydrogen-bond inter-actions are formed. These inter-actions link the mol-ecules into hydrogen-bond dimers. The side chains of the two cations have slightly different orientations. The 1-propanol solvent mol-ecule is linked to a bromide ion by an O-H⋯Br hydrogen bond.

Polyethylenimine-cyclodextrin-tegafur conjugate shows anti-cancer activity and a potential for gene delivery.

Polyethylenimine-cyclodextrin-tegafur (PEI-CyD-tegafur) conjugate was synthesized as a novel multifunctional prodrug of tegafur for co-delivery of chemotherapeutic agent tegafur and enhanced green fluorescent protein (EGFP) reporter plasmid DNA. Conjugation of tegafur to PEI-CyD via chemical linkage was characterized by (1)H NMR spectrometry and ultraviolet (UV) spectrometry. PEI-CyD-tegafur was able to condense plasmid DNA into complexes of around 150 nm with positive charge at the N/P ratio of 25, in accordance with electron microscopy observation of compact and monodisperse nanoparticles. The results of in vitro experiments showed enhanced cytotoxicity and considerable transfection efficiency in B16F10 cell line. Therefore, PEI-CyD-tegafur may have great potential as a co-delivery system with anti-cancer activity and potential for gene delivery.

Febuxostat methanol solvate.

In the title compound {systematic name: [2-(3-cyano-4-isobutyl-oxyphen-yl)-4-methyl-1,3-thia-zole-5-carb-oxy-lic acid (febuxostat) methanol monosolvate}, C(16)H(16)N(2)O(3)S·CH(4)O, the benzene and thia-zole rings in the febuxostat mol-ecule are twisted at 5.3 (1)°. In the crystal structure, inter-molecular O-H⋯O and O-H⋯N hydrogen bonds link the febuxostat and methanol mol-ecules into helical chains along the 2(1) screw axis.

Gene delivery to tumor cells by cationic polymeric nanovectors coupled to folic acid and the cell-penetrating peptide octaarginine.

Target ligand folic acid (FA) and cell-penetrating peptide octaarginine (R8) were coupled with the gene vectors (PEI(600)-CyD, PC) composed of ß-cyclodextrin (ß-CyD) and low-molecular-weight polyethylenimine (PEI, Mw 600) to form nanovectors for highly efficient gene delivery to tumor cells. The resultant ternary nanocomplexes of FA-PC/R8-PC/pDNA produced excellent gene transfaction abilities in the folate receptor (FR)-positive tumor cells in vitro and in vivo. The FR-mediated endocytosis and the R8-mediated transmembrane functionality together contributed to the high transfection levels. This study provides a promising means to produce gene nanovectors for in vivo applications.