RESUMEN
Two Mn(II)-bridged Silverton-type {UMo12O42}-based polyoxomolybdates with different three-dimensional structures, Na6(H2O)12[Mn(UMo12O42)] (NaMn) and (NH4)2[K2Na6(µ4-O)2(H2O)1.2Mn(UMo12O42)]·4.6H2O (KMn), were hydrothermally synthesized and further characterized, demonstrating a feasible strategy for the assembly of Silverton-type polyoxomolybdates. Additionally, NaMn is demonstrated to be a good heterogeneous catalyst in the condensation cyclization reaction of hydrazines and 1,3-diketones, and a range of valuable pyrazoles were produced in up to 99% yield.
RESUMEN
Multicistronic vectors can increase transgene expression and decrease the imbalance of gene expression in the Chinese hamster ovary (CHO) cell expression system. Small, self-cleaving 2A peptides have a high cleavage efficiency and are essential for constructing high-expression multicistronic vectors. In this study, we investigated the effects of two different 2A peptides on transgene expression in CHO cells via their mediating action on tricistronic vectors. The enhanced green fluorescent protein (eGFP) and red fluorescent protein (RFP) genes were linked by the porcine teschovirus-1 (P2A) and Thosea asigna virus (T2A) peptides in a multicistronic vector. We transfected CHO cells with these vectors and screened for the presence of blasticidin-resistant colonies. Flow cytometry and real-time quantitative PCR (qPCR) were used to detect the expression levels of eGFP and RFP and the copy numbers of stably transfected cells. The results showed that P2A could enhance eGFP and RFP expression by 1.48- and 1.47-fold, respectively, compared to T2A. The expression levels of the genes were not proportional to their copy numbers. In conclusion, we found that P2A can effectively drive transgene expression in CHO cells and a potent 2A peptide can be used for recombinant protein production in the CHO cell system.
Asunto(s)
Vectores Genéticos/genética , Péptidos/genética , Proteínas Recombinantes/genética , Transgenes/genética , Animales , Células CHO , Cricetinae , Cricetulus , Dosificación de Gen , Proteínas Luminiscentes/química , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Péptidos/química , Péptidos/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Transfección , Proteínas Virales/química , Proteínas Virales/genética , Proteínas Virales/metabolismoRESUMEN
A novel n-type organic semiconductor, Et-TITC, was synthesized by Knoevenagel condensation of truxenone and ethyl cyanoacetate. Ultrasonication improved the yield of Et-TITC by more than 10 times. The molecular structure of Et-TITC was determined by X-ray analysis. Et-TITC possesses a large electron affinity and excellent solubility in many organic solvents. A positively charged xerographic photoreceptor with an excellent photosensitivity (E 1/2) of 0.32 microJ cm(-2) was prepared using Et-TITC as the charge-transport material. [structure: see text]
RESUMEN
In the presence of a carbodiimine, i.e. DCC, a series of organoimido derivatives of polyoxometalates have been synthesized via the reaction of [alpha-Mo8O26]4- with aromatic amines and its hydrochloride salt. Elemental analysis, IR, 1H-NMR and UV-Vis spectra were used to characterize those hybrids, in particular their UV-Vis spectra have been studied. The results show that typical metal-ligand charge transfer (MLCT) transitions occur in the organic-inorganic hybrid molecules. There is a good linear relationship between the shift of UV-Vis absorptions (delta lamda max) and conjugation effect of the p-substituted group (sigmaR).
Asunto(s)
Compuestos Organometálicos/química , Espectrofotometría Ultravioleta , Espectrofotometría , Compuestos de Tungsteno/química , Carbodiimidas/química , Transferencia de Energía , Espectroscopía de Resonancia Magnética , Modelos Químicos , Estructura Molecular , Compuestos Organometálicos/síntesis químicaRESUMEN
Two sandwich-type complexes Na9n(Cu(im)4(H2O)2)1.5n(Cu(im)4(H2O))n[{Cu(im)4}{Na(H2O)2}3{Cu3(im)2(H2O)}(XW9O33)2]2n .(xH2O)n (im=imidazole, X=Bi (1), Sb(2), x=42.5 (1), 40 (2)) have been synthesized and structurally characterized. Basic frameworks of 1 and 2 are built from sandwich-type [{Na(H2O) 2} 3{Cu3(im)2(H2O)}(XW9O33)2](9-) (X=Bi or Sb) anions and [Cu(im) 4](2+) cations. The Cu(2+) and Na(+) ions in the central belt are coordinated by alpha-[XW9O33](9-) units, im, and water molecules to form {CuO4(im)}, {CuO4(H2O)}, and {NaO4(H2O)2} groups in which Cu (2+) ions are partially modified with im ligands. These groups connect alternately forming a six-membered ring including six alpha-[XW9O 33](9-) units. Neighboring anions are further linked by [Cu(im) 4](2+) cations to display an unprecedented anionic chain, which is first observed in sandwich-type tungsto-bismuthate (-antimonite) system. Two kinds of isolated copper complexes and sodium ions are located as counterions, which cause three-dimensional packings of 1 and 2 to present interesting cage structures. The magnetic properties for 1 and 2 both indicate dominant antiferromagnetic interactions among trinuclear Cu(II) clusters.
RESUMEN
An organic-inorganic hybrid compound, poly[bis[(pyridine-4-carboxylato)zinc(II)]-di-mu3-phosphato], [Zn2(C6H5NO2)2(HPO4)2], has been hydrothermally synthesized and structurally characterized. The crystal structure consists of two types of two-dimensional layers of zinc hydrogenphosphate templated by protonated isonicotinate (ina) (or 4-pyridinecarboxylic acid), which contain two crystallographically independent centrosymmetric [Zn2(ina)2(HPO4)2] dimers as basic building units. The layers are interconnected via hydrogen-bonding and heterocyclic ring interactions.