Osmotic Regulation of Betaine Content in Leymus chinensis Under Saline-alkali Stress and Cloning and Expression of Betaine Aldehyde Dehydrogenase（BADH） Gene

The potted Leymus chinensis seedlings were treated with saline-alkali solution of six different（from Ⅰ to Ⅵ） concentrations. The results demonstrate that the betaine content and Betaine-aldehyde dehydrogenase（BADH： EC 1.2.1.8） activities have a direct relation with increased stressing time in the same treatment; both exhibit a single peak with increasing the concentration of saline-alkali solution, and number V shows the highest value. The BADH gene of Leyrnus chinensis was cloned by RT-PCR and RACE technology and was designated as LcBADH. The cDNA sequence of LcBADH was 1774bp including the open reading frame（ORF） of 1521bp（coding 506 amino acids）. The vector of prokaryotic expression was constructed by inserting the LcBADH gene fragmcnt into pET30a（＋） and transformed into E. coli BL21（DE3）. The result of SDS-PAGE shows that the idio-protein with a molecular mass of 56.78 kDa was effectively expressed in the recombinant bacteria induced by isopropyl fl-D-thiogalactoside（IPTG）.     

Partial Molar Volume,Ionization, Viscosity and Structure of Glycine Betaine in Aqueous Solutions

Densities, partial molar volumes, and viscosities of aqueous solutions of betaine have been measured at 5, 10, 15, 20, 25, 30, 37, and 45 °C over the concentration range 0.05 to 5.0 mol⋅L⁻¹. The partial molar volumes show that betaine exists partly as a monohydrate and partly in its anhydrous form. The proportion of the anhydrous form increases with increasing temperature. Also, an associated form of betaine appears in concentrated betaine solutions, possibly with water as a bridging group. The significance of the viscosity B-coefficient is discussed. The signs of B _st, the increment of the viscosity B-coefficients arising from structural changes of water, are negative and the signs of dB/dT, the temperature derivative of B, are positive. These results show that betaine is a water structure breaker especially at lower temperatures, and this effect decreases to insignificance at higher temperatures. The ionization equilibria of betaine were investigated in aqueous 0.5 mol⋅L⁻¹ and 1.0 mol⋅L⁻¹ NaNO₃ at 5, 15, 25, and 37 °C by a potentiometric method. Using the least-square computer program SUPERQUAD, the complex forms are deduced to be betanium BH, bis(betanium) BHB, and bis(betaine) B₂ or bis(betaine)hydrate BH₂OB.     

Syntheses and Crystal Structures of Two New Mercury（Ⅱ） Complexes with Double Betaine Ligands

Reaction of HgCl2 and double betaine ligands in water at about 80 ℃ yielded two new Hg(Ⅱ) complexes,[Hg(L1)Cl2]·H2O 1 and [Hg2(L2)Cl4]·3HgCl2 2(L1 = 1,3-bis(pyridinio-4-carboxylato)-propane,L2 = 1,4-bis(pyridinio-4-carboxylato)-1,4-dimenthylbenzene).Their struc-tures have been characterized by single-crystal X-ray diffraction techniques.The structure of 1 contains 1-D chains,in which the adjacent Hg(Ⅱ) atoms are bridged by L1 ligands in a syn-syn bis-monodentate mode.The chains are further connected through face-to-face π-π stacking interactions between pyridine rings to generate an infinite double-chain network.In 2,two Hg(Ⅱ) atoms are joined by L2 ligands in the same coordination mode as 1 to form an isolated dinuclear structure.The thermal stabilities of both complexes have also been investigated.     

Synthesis and Structural Characterization of a New Cadmium(II) Complex with a Double Betaine

1 INTRODUCTION The construction of supramolecular aggregates has received much attention due to their intriguing network topologies and potential functions as new classes of materials[1, 2]. Multiple noncovalent interac- tions, such as hydrogen bonds, π-π stacking and host- guest ionic interactions, play important roles in the supramolecular assembly of metal ions and organic ligands[3, 4]. In this context the multidentate ligands with conjugated groups are employed as building blocks in…     

Syntheses and Crystal Structure of Erbium(Ⅲ) Coordination Polymers with Two Flexible Double Betaine Ligands

1INTR0DUCTI0NLanthanidecarboxylatecomplexeshavebeenwidelystudiedt1iandm0starefoundtoexhibitavarietyofdimericorinfinitechainstructures.Recentstudiesinourlaboratoryhavedem0nstratedthattheprototypetertiaryaminebetaine(Me,N CHzC0z-)anditsderivativesareusefulinthegenerationoflanthanidecarb0xylate-likecomplexeswithnewstructuralfeaturesduetotheiroverallchargeneutralityandpossibleinclusionofvariouskindsofcounteranionsinthestructuret2~4i.Thelan-thanidecomplexesisolatedsofarhavebeenfoundtobemononu…     

Characterization and Crystal Structures of Two Copper（Ⅱ） Complexes Constructed by a Flexible Double Betaine Ligand

A flexible double betaine 1,4-bis(pyridinil-4-carboxylato)-1,4-dimethylbenzene L has been used to generate two Cu(II)-containing metal complexes that exhibit different polymeric structures: [Cu(H2O)2 L]·2NO3 1 and [Cu(H2O)3 L]·2Cl·H2O 2. The crystal structures of 1 and 2 have been determined by single-crystal X-ray diffraction method. Crystal data for 1: triclinic, space group P 1, a = 5.253(2), b = 7.406(3), c = 14.792(5) , α = 84.195(5), β = 80.014(5), γ = 78.053(5)°, V = 553.2(3) 3, Z = 1, F(000) = 293, Dc = 1.717 g/cm3, the final R = 0.0385 and wR = 0.1079 for 1883 observed reflections (I > 2σ(I)); and those for 2: monoclinic, space group P21/c, a = 10.222(3), b = 25.287(7), c = 9.277(3) , β = 93.572(5)°, V = 2393.2(12) 3, Z = 4, F(000) = 1140, Dc = 1.540 g/cm3, the final R = 0.0472 and wR = 0.0956 for 3204 observed reflections (I >2σ(I)).     

Characterization and Crystal Structures of Two Copper(Ⅱ) Complexes Constructed by a Flexible Double Betaine Ligand

A flexible double betaine 1,4-bis(pyridinil-4-carboxylato)-1,4-dimethylbenzene L has been used to generate two Cu(II)-containing metal complexes that exhibit different polymeric structures: [Cu(H2O)2 L]·2NO3 1 and [Cu(H2O)3 L]·2Cl·H2O 2. The crystal structures of 1 and 2 have been determined by single-crystal X-ray diffraction method. Crystal data for 1: triclinic, space group P 1, a = 5.253(2), b = 7.406(3), c = 14.792(5) , α = 84.195(5), β = 80.014(5), γ = 78.053(5)°, V = 553.2(3) 3, Z = 1, F(000) = 293, Dc = 1.717 g/cm3, the final R = 0.0385 and wR = 0.1079 for 1883 observed reflections (I > 2σ(I)); and those for 2: monoclinic, space group P21/c, a = 10.222(3), b = 25.287(7), c = 9.277(3) , β = 93.572(5)°, V = 2393.2(12) 3, Z = 4, F(000) = 1140, Dc = 1.540 g/cm3, the final R = 0.0472 and wR = 0.0956 for 3204 observed reflections (I >2σ(I)).     

Syntheses and Crystal Structures of Two New Ag(Ⅰ) Complexes with Betaine Derivative: Structure Changes via Metal-to-ligand Ratio

Two new Ag(I) complexes {Ag2(L)(NO3)(H2O)}n(1) and {Ag(L)}n·nH2O(2) have been synthesized via the reaction of silver nitrate and betaine derivative 1-carboxymethylpyridinium-3-carboxylate(L) by only changing the metal-to-ligand ratio. The results of X-ray crystallographic analysis indicate that complexes 1 and 2 both crystallize in the monoclinic space group P21/c with a = 5.0809(14), b = 17.390(5), c = 13.399(4), β = 91.677(5)o, V = 1183.4(6)3, Z = 4, Mr = 475.90, Dc = 2.671 g/cm3, F(000) = 912, μ = 3.352 mm-1, S = 1.259, the final R = 0.0320 and wR = 0.0831 for 2036 observed reflections with I 2σ(I) for 1 and a = 12.180(2), b = 5.0283(10), c = 14.396(3), β = 94.87(3)o, V = 878.5(3)3, Z = 4, Mr = 306.02, Dc = 2.314 g/cm3, F(000) = 600, μ = 2.294 mm-1, S = 1.053, the final R = 0.0283 and wR = 0.0684 for 2011 observed reflections with I 2σ(I) for 2. Complexes 1 and 2 both feature a unique 2D structure. For 1, the 2D undulated network consists of 1D infinite helical chains running parallel to the b axis, while for 2, the 2D network is made up of 1D tubes along the b axis. Moreover, the Ag…Ag interactions in complexes 1 and 2 are also discussed.     

Simple synthesis and separation of the diastereomers of α-thio analogs of ribo- and deoxyribo- di- and triphosphates

Nucleoside 5′-0-(1-thiodi-) and triphosphates can be obtained in yields of up to 45% directly from the nucleosides. Their diastereomers can be separated by preparative reversed phase chromatography.     

Interactions and influence of α-cyclodextrin on the aggregation and interfacial properties of mixtures of nonionic and zwitterionic surfactants

The interactions of α-cyclodextrin (α-CD) with the nonionic surfactant decanoyl-N-methyl-glucamide (Mega-10) and the zwitterionic surfactant dimethyldodecylammoniopropanesulfonate (DPS) in their mixed system have been studied using interfacial tension, fluorescence, and nuclear magnetic resonance measurements. From the plots of interfacial tension vs. log of total surfactant concentration, we have obtained values of the surface excess of surfactant, the critical micellar concentration (cmc), the standard free energy of micelle formation, and association constant of surfactant/α-CD inclusion complexes (assuming a 1:1 stoichiometry). A comparison of the K _a values obtained for the interaction between α-CD and DPS and Mega-10, respectively, shows that DPS interacts stronger with α-CD than Mega-10. The experimental mixed cmc was analyzed by the pseudophase separation model and regular solution theory for the evaluation of ideality or nonideality of the mixed micelle formation. The interaction parameters in the mixed micelle and the micelle composition at different mole fractions of DPS were also computed. The fluorescence anisotropy (r) values of rhodamine B decreases with the increase of α-CD concentrations.     

Synthesis and Spectroscopic Characteriration of Transition MetalComplexes of Maleionitriledithiolene and 1,10-Phenanthroline

Thedithiolenesanddiiminesandtheirmetalcomplexesareanimportantresearchfieldintheorganicandcoordinationchemistry'-'.Metalcomplexesofadithioleneandadiiminehaveexcellentelectronicfullctionsduetotheintramolecularchargetransferfromaligandtootherligand(LL'C...     

Synthesis and Structure of Tetraphenylglycolide

1 INTRODUCTION Polylactide usually synthesized by a con-densation reaction of glycolide is a kind of use-ful medical polymer. Several structures of gly-colide derivatives have been determined by X-ray diffraction[1], and their molecular struc-tures showed the significant influence of subs-tituents on the conformation of glycolide hete-rocycle. The title glycolide derivative has beenrecently synthesized in laboratory, and its X-ray structure is presented herein to compare themolecular stru…     

Synthesis and study of the cyclization pathways and reactivities of α-diazoimidolates

The reaction of unsymmetrical N,N-disubstituted malonamides with benzenesulfonyl azide in the presence of sodium ethoxide gives individual sodium 1,2,3-triazol-5-olates or mixtures of their isomers, from the relative amounts of which the effect of substituents in the amido groups on the cyclization pathways and reactivities of -diazoimidolates was ascertained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1521–1527, November, 1991.     

Synthesis and Characterization of ABBA Block Copolymer of Glycolide and ε-Caprolactone

A biodegradable ABBA block copolymer was synthesized via the ring-opening co-polymerization of ε-caprolactone(CL, B) and glycolide(A) by means of step polymerization in the presence of ethylene glycol as an initiator and stannous octanoate as a catalyst at 110 ℃ for 48 h. The molecular length of the PCL pre-polymer(BB) could be adjusted by controlling the molar ratio of the ethylene glycol initiator to ε-caprolactone monomer. The structure and the composition of the block copolymer were determined by the weight ratio of the monomer glycolide(A) to PCL pre-polymer(BB). The block copolymers were characterized by 1H NMR, GPC, DSC and X-ray. The results confirm the successful synthesis of an ABBA block copolymer.     

Donor-Acceptor Oligomers and Polymers Composed of Benzothiadiazole and 3-Hexylthiophene： Effect of Chain Length and Regioregularity

A series of donor-acceptor oligomer OBTThn （n = 1- 7） and polymer PBTThl and PBTTh2 composed of al- ternative 2,1,3-benzothiadiazole and 3-hexylthiophene have been designed and synthesized for the purpose of in- vestigation on the effect of chain length and side-chain regioregularity on their basic properties and photovoltaic performance. In the OBTThn oligomers and PBTThl polymer, all the hexyl side chains on thienyl units orient to- ward the same direction. Upon elongation of the chain length, the intramolecular charge transfer （ICT） absorption band in solution gradually redshifts from 398 nm for OBTThl to 505 nm for OBTThT, then to 512 nm for PBTThl polymer. Meanwhile, the HOMO energy level increases from -5.45 eV （OBTTh0 to -5.08 eV （OBTThT） and -5.09 eV （PBTThl）, and the LUMO energy level decreases from -3.11 eV （OBTTh0 to -3.30 eV （OBTThT） and -3.33 eV （PBTThl）, thus giving a smaller and smaller energy bandgap for higher oligomers and polymers. Theo- retical calculation suggests straight line-like backbone geometry for this series of oligomers and polymer. On the other hand, polymer PBTTh2 possesses a different side-chain regioregularity, in which every two neighbor hexyl side chains are arranged in different orienting direction. It is theoretically suggested to have curved line-like back- bone geometry. In solution, it shows similar photophysical and electrochemical properties as PBTThl. However in film state, it displays a less redshift in the ICT band as refer to that in solution than PBTThl. In combination with [6,6]-phenyl-C61-butyric acid methyl ester （PC61BM）, these oligomers and polymers were used as donor material to fabricate organic bulk heterojunction solar cells. Again, chain length-dependent device photovoltaic performance was observed. The device based on OBTTh4 showed a power conversion efficiency of 0.16%, while it increased to 0.36% and 0.49% for the devices based on OBTTh6 and PBTThb respectively. However, the side-chain regio- regularity has less influence on the device photovoltaic output since the device based on PBTTh~ displayed an effi- ciency of 0.52%, comparable to that of PBTThl.