bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparative separation of factors B (virginiamycins S) from commercial feed additive formulations
Authors: Sharma N. K. , Anteunis M. J. O. 
Published: September 2010

AbstractMixtures of VS1 and VS4 (1) can be preparatively separated by adsorption chromatography on SiO2 with benzene: isobutanol: acetic acid (90: 30: 5) as the eluent system. The purity of the separated congeners was checked by HPLC and H NMR. Although analytically highly efficient eluent systems have been found for similar separations by reverse phase HPLC, this method suffers from difficulties that are big enough as to render this approach less practical for preparative purposes.
α‐Silyl trimethylsilyl esters from aliphatic carboxylic Acid Dianions
Authors: Bellassoued M. , Dubois J. E. , Bertounesque E. 
Published: September 2010

AbstractThe synthesis of α‐silyl trimethylsilyl esters from aliphatic carboxylic acid dianions is reported. The results indicate kinetic and thermodynamic control of silylation of acid dianions.
α‐Cyano‐β‐styrenyl esters for amide bond formation
Authors: Roose B. , Anteunis M. J. O. , Tavernier D. 
Published: September 2010

AbstractP‐X‐α‐cyano‐β‐styrenyl esters (X = H, Cl, CF3, NO2) of N‐benzyloxycarbonyl valine were prepared. The rate constant for amide formation with methyl valinate was assayed; it increases with increasing electron attracting power of the para substituent. The N‐hydroxysuccinimidoyl ester and the p‐H‐α‐cyano‐β‐styrenyl ester of valine have comparable reactivities.
Structure of 4‐ (N'‐Pivaloyl)‐D‐Phenylalanyl‐L‐Perhydro‐4H‐1,4‐Thiazine‐3‐ (N‐Methyl) Carboxamide in the Crystalline State
Authors: Wu S. , Tinant B. , Declercq J. P. , van Meerssche M. , Borremans F. A. M. , Anteunis M. J. O. 
Published: September 2010

AbstractC20H29N3O3S, tetragonal, Mr = 391.53, P43212, a = b = 11.688 (1), c = 31.017 (4) Å, Z = 8, Dx = 1.23 g. cm−3, CuKα, λ = 1.5418 Å, μ = 15.17 cm−1, F (000) = 1680, T = 291K, R = 0.055 and RW = 0.061 for 3913 reflections with I ≥ 2.5σ (I) out of 4264 Independent measurements. The peptide chain adopts a conformation of the type II'β turn (ϕ1 = 56°, Ψ1 = −127°, ϕ2 = −93°, Ψ2 = 21°) which is stabilised by an intramolecular H‐bond between the NH of the methylcarboxamide group and the C=O of the pivaloyl moiety. The 4‐thiapipecolic ring has a chair conformation. The torsion angles of the side chain of the Phe residue are χ1 = −179°, χ21 = −80°. The central amide bond is substantially distorted mainly by out‐of‐plane bending of the imino nitrogen (χN = +14°) Thus, conflicting constraints are relaxed, that are imposed by the geometric requirements of the chair form (χ6 = −54°) and of the type II'β turn (ϕ2 ∼ 90°).
Benzylation of Virginiamycin S1
Authors: Sharma N. K. , Anteunis M. J. O. 
Published: September 2010

AbstractTreatment of Virginiamycin S1 (VS1) with benzyl bromide in the presence of potassium fluoride in DMF at r. t. resulted in quantitative formation of 1′‐N‐Bzl‐VS1 (1) exempt of 1′‐O‐Bzl‐VS1 (2). A 27% conversion of VS1 into 2 however could be achieved by treatment of VS1 with benzyl bromide in DMF at r. t. in the presence of 1, 8‐bis (dimethylamino) naphthalene as the base. The structure of 1 was confirmed by 1D and 2D NMR spectroscopy.
Synthèse Des Pyrazolo [2, 3‐b] Benzotriazepines‐1, 3, 5 A Partir Des Alkyl‐1 Benzodiazepine 1, 5 Ones‐2
Authors: Essassi E. M. , Salem M. 
Published: September 2010

AbstractThe addition of hydrazine to 1‐alkyl 1,5‐benzodiazepine‐2‐thiones yields 1‐(N‐alkyl N‐amino pyrazolyl)‐2‐amino‐benzenes. These compounds react with orthoesters and phosgene to give new heterocycles : pyrazolo 2, 3‐b 1, 3, 5 benzotriazepines.
Quantification of phospholipid phosphorus in sub‐micromolar concentrations
Authors: van Der Meeren P. , Vanderdeelen J. , Baert L. 
Published: September 2010

AbstractA safe, simple, rapid and very sensitive technique is described for the quantitative estimation of phospholipid phosphorus. In comparison with other procedures, our method is shown to be particularly advantageous for very diluted phospholipid solutions.The main feature of the method was the acid digestion of large volumes in Kjeldahl flasks. After neutralization, the inorganic phosphate was determined spectrophotometrically.Using soybean lecithins, both the precision and accuracy of the method were elaborated. The coefficient of variation amounted to at most 1.5% and the sensitivity was reduced to 500 nM of phospholipids.
Simultaneous Use of N‐Fmoc and OTmse Protective Groups in the Synthesis of Peptolytic Sensitive Peptides
Authors: Vanfleteren L. , Anteunis M. J. O. 
Published: September 2010

AbstractThe combined use of Fmoc (fluorenylmethoxycarbonyl) as N‐protection and Tmse (trimethylsilylethyl) as O‐protection during demanding fragment condensation mediated by Bop‐Cl (N, N′‐bis(3‐oxo‐2‐oxazolidinyl)phosphinyl chloride) has been explored in the preparation of useful synthons that are sensitive to acidic and even basic hydrolyses. Stepwise deprotection by morfoline (Fmoc‐deprotection) followed by F⊖‐mediated removal of Tmse results in a very effective peptide synthesis strategy, as exemplified by the preparation of i. a. Phg‐MePhe‐Thz. Similarly, combinations of N‐Bc, O‐Tmse peptide esters are also possible that allow the preparation of ⊕H2‐MePhe‐Thz‐OTmse (via Boc‐MePhe‐Thz‐OTmse) without competitive DKP formation.
α,α‐Dichloroaldehydes and α,α‐Dichlorocarboxylic Acids from Long Chain 1‐Alkanols. Improved Chlorination in the System DMF‐CHCl3‐MgCl21
Authors: De Buyck L. , Casaert F. , De Lepeleire C. , Schamp N. 
Published: September 2010

AbstractProduction of α,α‐dichloroaldehydes by direct chlorination of 1‐alkanols with chlorine gas, catalyzed by DMF and DMF. HCl, was extended to long chain compounds (CnH2n+1OH; n = 5,6,8,10,12,14,16,18). Two problems specific to the longer chains were solved to obtain isolated yields in the range 70‐85%; a) parasitic radical chlorination was largely controlled by shielding from light; b) alkyl alkanoate side product (8% for n=8 but ˜ 25% for n=16 or 18) was decreased to 0‐2% in the presence of MgCl2.H2O. Homogeneity of the reaction medium was improved with chloroform as a cosolvent.Oxidation of the aldehydes to dichlorocarboxylic acids proceeded smoothly with aqueous KMnO4up to the tetradecanal. For the longer chains 30% hydrogen peroxide‐NaHCO3in acetone (overnight at 48‐52°C) was the preferred oxidant.
Complexation of neutral guest molecules by synthetic macroheterocyclic hosts
Authors: Reinhoudt David N. , Den Hertog Herman J. 
Published: September 2010

AbstractMacroheterocyclic molecules can be used to organize the binding sites required for selective molecular recognition and/or molecular catalysis. Although most work in the literature deals with recognition of ionic species, there is an increasing interest in the selective complexation of neutral molecules. Based on X‐ray analysis of solid complexes and NMR in solution, hydrogen bonding of host to guest and/or vice versa determines the structure, and very likely also the stability of these complexes between neutral host and guests. This paper describes an NMR method to determine the (weak) association constants of such complexes. Subsequently, two strategies are described for the enhancement of the thermodynamic stability, viz. the introduction of (intraannular) acidic groups in the molecular cavity and the use of metallomacrocyclic hosts in which a ‘soft’ cavity is combined with a ‘hard’ macrocyclic moiety. For both approaches novel synthetic methodology has been designed and for the first approach, the pKa values of acidic groups present in molecular cavities have been studied. Finally we have used the novel metallomacrocycles to organize two (or more) different metal centres in molecular cavities.
Large scale preparation of versatile chiral auxiliaries derived from (S)‐proline1
Authors: Enders Dieter , Kipphardt Helmut , Gerdes Peter , Breña‐Valle Leonardo J. , Bhushan Vidya 
Published: September 2010

AbstractThe synthesis of a variety of enantiomerically pure chiral auxiliaries based on (S)‐proline and bearing sterically demanding side chains at the pyrrolidine moiety, such as the secondary amines (S)‐3,5 and 7 and the hydrazines (S)‐6, is described on a molar scale. As key step, the Grignard or RLi addition to the N‐benzylated proline ester (S)‐1 is used.
Ring opening of 2,2,4,6,6‐pentachloro‐4‐fenyldimedone affording an α,α‐dichloro‐γ‐butyrolactone
Authors: De Buyck L. , De Pooter H. , Schamp N. 
Published: September 2010

AbstractAn α, α‐Dichloro‐γ‐butyrolactone 4 was formed after ring opening of 2,2,4,6,6‐pentachloro‐4‐fenyldimedone with NaOAc‐HOAc in aqueous dioxane. The ring opening in methanol gave a δ‐ketoester 5 which was cyclised with Na2CO3 to afford the cyclic enol ether 6.
Fundamental questions about entropy IV. The hydrophobicity of alkanes: A nearly pure entropic effect
Authors: Huyskens P. L. , Siegel G. G. 
Published: September 2010

AbstractThe low solubility of low‐molecular weight alkanes in water is not due to the necessity of breaking H‐bonds in water upon introducing the solute. It is also not due to the breaking of a special kind of cohesion forces “hydrophobic interactions” in the organic liquid. Experimental evidences are given demonstrating that the hydrophobic effect of water and alcohols with respect to liquid alkanes is nearly purely entropic. The introduction of the alkane has practically no influence on the fraction γ but extends the standardized domain <DomA> of one molecule of the hydrogen bonded liquid. The hydrophobic effect is essentially due to this extension of the territory of the mobile order. To a good approximation the increase of the chemical potential of the alkane caused by this effect is given by μHB = ‐nAT(∂ΔS̄A mobile order/∂nB). On the other hand, contrary to the assumptions of multicomponent theories, the combinatorial entropy of the mixture is practically not affected by the presence of the H‐bonds. From the value of the combinatorial entropy derived in part two, and neglecting all enthalpic effects one derives an equation predicting the solubilities of alkanes in water (in volume fractions) ϕB = exp (0.5(V̄B/18‐1) + 0.5lnV̄B/18 ‐ 2V̄B/18). This equation, that does not contain any adjustable parameter, predicts the solubility of all the alkanes within 50% error in a domain which varies from 10−4 to 10−7 volume fraction.
Molecular orbital calculations on oxygen deficient YBa2Cu3O7−x clusters
Authors: D'Heer J. , Hoste S. , van Der Kelen G. P. 
Published: September 2010

AbstractWe have carried out semiempirical molecular orbital calculations (charge iterative EHMO) on different clusters representing YBa2CU3O7‐x. (O < x <1). Charges on the various atoms suggest transport of charge occurs in the CuO2−planes, rather than in the CuO‐chains. The Fermi level energy is found to increase with x. Strong d‐states about 10 eV above the Fermi level are found. Analysis of the highest occupied orbitals shows the importance of Cu 3dx2 ‐ y2 and O 2px, 2py orbitals.
Synthesis, characterization and antitumour activity of a series of diorganotin(IV) compounds of the type Bu2Sn(O‐X‐Y‐O)
Authors: Gieien Marcel , Vanbellinghen Christel , Gelan Jan , Willem Rudolph 
Published: September 2010

AbstractThe synthesis and characterization of a series of diorganotin(IV) derivatives of bifunctional phenol‐alcohols, hydroxyacids and acid‐phenols are described. They exhibitin vitrocytostatic properties against P388 and L1210 leukemiae.
Structure Géométrique Et Électronique De Trois Dérivés Analogues Du Butanedinitrile‐1,4
Authors: Tinant B. , Parfonry A. , Declercq J. P. 
Published: September 2010

AbstractFrom X‐ray measurements at 155K, the electronic deformation densities for 1,1,2,2‐ethanetetracarbonitrile(1) and meso 2,3‐dimethyl‐2,3‐bis(p‐cyanophenyl)‐1,4‐butanedinitrile(2) have been obtained by multipolar refinement. Comparison of the maps does not show any indication of substitution effects. The X‐X deformation maps obtained for 2,3‐dimethyl‐2,3‐diphenyl‐1,4‐butanedinitrile(3) show an orientational disorder with a very weak occupation of the second orientation. This explains the abnormal bond lengths that were observed at room temperature.
A five parameter factorial analysis for copper deposition on a platinum rotating disc electrode in galvanic solutions
Authors: Mertens M. , Temmerman E. , Verbeek F. 
Published: September 2010

AbstractA cyclic voltammetric stripping technique is used to analyse the influence of five parameters on the copper deposition at a rotating platinum ring‐disc electrode. The impact of two pretreatment methods, carbon and electrolytic, and the concentration variations of sulphuric acid, copper sulphate and chloride ions are evaluated in a factorial analysis using the Yates algorithm. Extra information is gathered by electrogravimetric and X‐ray diffraction techniques. The most significant single factors are the copper sulphate and chloride ion concentrations. Carbon treatment with sulphuric acid concentration and electrolytic pretreatment with copper sulphate concentration are important hybrid factors, i. e. with mutual influence.
Synthèse D'α‐(Arylamino)Benzylphosphonates De Bis‐β'‐Chloréthyle
Authors: Smolders Robert René , Brunin Dominique , Sarto Frédéric 
Published: September 2010

AbstractBis‐(β′‐chlorethyl)‐α‐(arylamino)benzylphosphonates, potential antitumor agents, have been synthetised by reaction between bis‐(β‐chlorethyl)phosphonate and four N‐benzylidenenaphtylamines or the 4‐[γ‐(methoxycarbonyl)propyl]‐N‐{ p‐[bis‐(β′‐chlorethyl)amino]}benzylideneaniline.
1,4,5,8‐Tetra‐Azaphenanthrene Complexes of Copper(I) and Silver(I)
Authors: Nasielski J. , Nasielski‐Hinkens R. , Heilporn S. , Rypens C. , Declercq J. P. 
Published: September 2010

AbstractCu(l) and Ag(l) complexes of 1,4,5,8‐tetra‐azaphenanthrene (TAP) and of two of its methylated derivatives (3,6‐dimethyl‐ and 2,3,6,7‐tetramethyl‐) have been made and characterized. Their HNMR spectra are discussed. The structure of the complex Ag(TAP)2(NO3), as determined by X‐Ray crystallography, is that of a strongly folded and twisted square planar arrangement of the chelating ligands around the silver atom; the four Ag‐N bonds are not equal: they are shorter (2.36 Å) in one pair oftransbonds than in the other (2.56 Å). 3,6‐Dimethyl‐1,4,5,8‐tetra‐azaphenanthrene (3,6dmTAP), a new TAP derivative, has been synthesized starting from 2‐hydroxy‐3‐methylquinoxaline which was nitrated, then treated with POCl3, the resulting 2‐chloro‐3‐methyl‐6‐nitroquinoxaline reacted with hydrazine and the hydrazino group oxidized to give 3‐methyl‐6‐nitroquinoxaline. This was aminated with hydroxylamine, reduced to the diamine and finally condensed with glyoxal to give 2,6‐dimethyl‐ and 3,6‐dimethyl‐1,4,5,8‐tetra‐azaphenanthrene.
The effect of anchoring substitution on the course of a cation olefin bicyclization. Crystal structure of (±)‐(2R, 3′R,5′S)‐2‐(3′‐tert‐Butyl‐5‐Isopropl‐5′‐Methyl‐1′‐Cyclopentenyl)‐1‐Cyclopentanone
Authors: Missiaen Patrick , De Clercq Pierre J. , van Meervelt Luc , King Geoffrey S. D. 
Published: September 2010

AbstractThe SnCl4−induced cyclization of aldehyde (Z)‐1 gives rise to a bicyclic alcohol in high yield, the rearranged structure of which was assigned via X‐ray diffraction of its oxidation product 2. The structure (C18H30O, P21/c, a = 11.253(1), b = 6.990(1), c = 22.260(4)Å, β = 78.17(2)°; Dm = 1.02(1) g. cm3, Dc (Z=4) = 1.017 g. cm−3) has been solved by direct methods and refined to a final R value of 0.086 for 1014 observed reflections.
Comparaison de L'Action Inhibitrice de Certains Halogènométhanes Sur la Propagation des Flammes
Authors: Da Cruz F. N. , Vandooren J. , van Tiggelen P. 
Published: September 2010

AbstractThis systematic study is focused on the influence of the addition of several halogenated fluorocarbon compounds (CF4, CF3H, CF3Cl, CF3Br, CF2Cl2, CFCl3) on the burning velocities and final temperatures of stoichiometric CO/O2/Ar/H2 flames. The inhibiting strength decreases along the sequence CF3Br > CFCl3 > CF2Cl2 > CF3Cl > CF3H > CF4 Moreover, the inhibition effect is more pronounced for CO/O2/Ar flames either containing low quantities of H2, or in lean mixtures.The competition between the reaction of the inhibitor scavenging hydrogen atoms and the branching reaction (H + O2 → OH + O) is the main process for inhibition. The rate constants and the activation energy of the individual trapping reactions of the inhibitor must be in between specified limits. The efficiency of the inhibitor is closely related to the rate constants and the activation energy of the primary trapping process. Nevertheless, the occurrence of Br or Cl atoms in the inhibition molecule enhanced the inhibition effect by subsequent scavenging reactions.
Lead tetraacetate oxidation of (Z)‐ and (E)‐5, 10‐Secocholest‐1 (10)‐ENE‐3β,5α−Diol 3‐acetate1
Authors: Mihailović Mihailo Lj. , Kruščić Natalija , Pavlović Vladimir , Lorenc Ljubinka 
Published: September 2010

AbstractThe lead tetraacetate oxidation of (Z)‐5, 10‐secocholest‐1(10)‐ene‐3β,5α−diol 3‐acetate (1) gave products arising from: (i) conversion of the 5α−hydroxy group to the ketone function (2), (ii) intramolecular cyclization (to the 2α,5α−tetrahydrofurane‐type ether 3), and (iii) allylic acetoxylation at the C(9) position (3 and 4), while similar oxidation of (E)‐5, 10‐secocholest‐1 (10)‐ene‐3β,5α−diol 3‐acetate (5) afforded mainly the product formed by conversion of 5α−OH to the keto‐carbonyl group (6).
1‐Organo‐4,4‐Dimethyl‐1,4‐Phosphastanninanes
Authors: Weichmann H. , Rensch B. , Dargatz M. , Meunier‐Piret J. 
Published: September 2010

AbstractThe title compounds Me2Sn(CH2‐CH2)2PR (1:R=Ph;2:R=t‐Bu) were prepared by hydrostannation of (CH2=CH)2PR with Me2SnH2. Oxidation with chalcogenes and reaction with Mel yields the corresponding P‐derivatives Me2Sn(CH2‐CH2)2P(X)R (3 ‐ 7:X=O, S, Se) and Me2Sn(CH2‐CH2®2Pr̀ MePh I−(8). NMR data (1H, 13C, 119Sn, 31P) suggest for 1 ‐ 8 a rigid chair conformation with the P‐substituent R being equatorially orientated. This conclusion was confirmed by the X‐ray analysis of 3 which revealed that the chair is flattened at the tin segment and puckered at the phosphorus part of the ring.
Isocyanates Bloques: Etude Cinetique Et Thermodynamique
Authors: De Aguirre I. , Collot J. 
Published: September 2010

AbstractA kinetic and thermodynamic study of the deblocking of urethanes is presented; the blocking agents are phenols, aliphatic alcohols and a polyether. The deblocking occurs via the elimination‐addition mechanism. In the transamination reaction, the rate determining step is the amine catalyzed dissociation of the blocked isocyanate. The equilibrium constants of these reactions give the relative stability of blocked isocyanates. The dissociation equilibrium of several urethanes were also determined; temperature higher than 170°C are required to obtain a significant dissociation in the case of usual urethanes.
Enantioselective Catalysis, 471Rhodium(II)‐Carboxylate Complexes and Their Use In the Enantioselective Cyclopropanation
Authors: Brunner H. , Kluschanzoff H. , Wutz K. 
Published: September 2010

Abstract13 optically active complexes of the type Rh2(OOCR*)4were synthesised, derived from optically active carboxylic acids R* COOH. The new rhodium(II) complexes were used as homogeneous catalysts for the cyclopropanation of styrene with ethyl diazoacetate. The product ethyl cis/trans‐2‐phenylcyclopropanecarboxylate was obtained with an optical induction up to 12 %ee.
Calculation of the Protonation Constants of Secondary N‐Chloramines
Authors: Antelo Juan M. , Arce Florencio , Franco Julia , Sanchez María , Varela Angel 
Published: September 2010

AbstractSpectrophotometric determinations of the pK of six secondary N‐chloramines have been used to obtain an empirical equation relating the pK of secondary N‐chloramines to those of the corresponding amines.
1H NMR and 13C NMR Study of Two Vincristine Derivatives at 300 Mhz
Authors: Bhushana Rao K. S. P. , De Bruyn André , Trouet André , Verzele Maurice , Hannart Jean 
Published: September 2010

Abstract13C, 1H heteronuclear shift correlated experiments allow to assign for the first time the 1H and 13C NMR parameters of 2 vincristine derivatives.
Oxidation of 2‐[2‐(3,4‐Dimethoxybenzylhydroxymethyl)‐4,5‐Dimethoxyphenyl]Ethanol Using Chromium (VI) Reagents
Authors: Domínguez E. , Iriondo C. , Laborra C. , Linaza A. , Martínez J. 
Published: September 2010

AbstractThe oxidation reaction of the title compound by means of chromium (VI) reagents afforded, not the expected dicarbonyl derivative, but cyclization compounds. Their structures determined on the basis of their spectral data are reported.
Synthesis, Physical Studies and Vibrational Spectra of the NI(II), Pd(II) and Cu(II) Complexes of N‐(2‐Aminoethyl)‐ and N‐(3‐Aminopropyl)Oxamide
Authors: Periepes Spiros P. , Quaeyhaegens Frank , Desseyn Herman O. 
Published: September 2010

AbstractThe new complexes K2[Ni(aeo)2]H2O, K2[Cu(aeo)2]·H2O, K2[Cu(aeo)2]·H2, K2[Ni(apo)2]·H2O, K2[Cu(apo)2]‐·2H2O, K2[Cu(apo)2·2H2O, K2[Pd(apo)2·2H2O and [Pd(Hapo)Cl]·0.5H2O, where H2aeo=N‐(2‐amino‐ethyl)oxamide and H2apo=N‐(3‐aminopropyl)oxamide, have been prepared. Several synthetic routes were investigated. The complexes were characterized by analyses, conductivity measurements, X‐ray diffraction, thermogravimetry, magnetic susceptibility measurements and spectral (IR and far‐IR, ligand field, ESR) studies. Monomeric square planar structures are assigned in the solid state for the [M(aeo)2]2− and [M(apo)2]2− anions in the complexes K2[Ni(aeo)2]H2O, K2[Cu(aeo)2]H2O (for both the rose and violet forms), K2[Ni(apo)2]H2O, K2[Cu(apo)2]·2H2O (rose form) and [Pd(Hapo)Cl]·0.5H2O; the doubly deprotonated aeo2 and apo2 ions exhibit a bidentate N(secondary amide), N′(tertiary amide)‐coordination with the ‐NH2 group remaining uncoordinated. Anionic oligomeric or polymeric elongated rhombic and distorted octahedral stereochemistries are proposed for the compounds K2[Cu(aeo)2]·H2O (green form) and K2[Cu(apo)2]·2H2O (royal blue form), respectively. The deprotonated CONH− group of Hapo− is coordinated to different Pd(II) atoms in [Pd(Hapo)Cl]·0.5H2O through both its nitrogen and oxygen atoms. The vibrational analysis of the monomeric complexes is given using NH/ND, NH2/ND2, 58Ni/62Ni and 63Cu/65Cu substitution.
Electrochemical Studies of Europium(III) in Potassium Sulfate Medium: The ko and α Values
Authors: Lopez V. 
Published: September 2010

AbstractPolarographic investigation of Eu(III)‐SO42− in aqueous solutions have been carried out with a dropping mercury electrode.The complex species in solution and the kinetic parameters ko and α of this system have been determined. The electrochemical behaviour depends on the SO42− concentration and pH.
Coordinative Properties Study and Preparation of a Resin Containing Polystyrene and Thiourea
Authors: Schmidt Ricardo , Förster Juan E. , Moya Sergio A. 
Published: September 2010

AbstractA matrix formed by reaction of styrene‐divinylbenzene copolymer with thiourea has been prepared and studied. The thiourea is covalently bound to the polymer matrix through the sulfur atom. The properties of the prepared resin have been studied with respect to the uptake of some ionic species such as: Cu(II), Zn(II), Fe(III), Au(III), Re(VII) and As(III).
The Michael Type Additions of Tetrazole Derivatives to Double and Triple Carbon‐Carbon Bonds
Authors: Dziklinska H. , Dzierzgowski S. , Jezewski A. , Plenkiewicz J. 
Published: September 2010

AbstractThe reactions of 5‐substituted tetrazoles, 1‐substituted tetrazolin‐5‐ones, and 5‐substituted 1‐hydroxytetrazoles with ethylene derivatives possessing electron withdrawing substituents were found to be of practical value in preparing variously substituted tetrazoles. 1‐Hydroxy‐5‐substituted tetrazoles, when treated with acetylene dicarboxylates, yield a mixture of (E) and (Z) isomers of Michael type addition product, which decomposes subsequently affording 2‐(2‐tetrazolyl)acetates. The formation of the latter corresponds with formal breaking of carbon‐carbon triple bond.