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Chemical Monthly - published by Springer
Chemical Monthly was originally conceived as an Austrian journal of chemistry, and has evolved into an international journal covering all branches of chemistry. It features the most recent research in analytical, inorganic, medicinal, organic, physical, structural, and theoretical chemistry, including chemically oriented areas of biochemistry.
pH-Sensitive hydrogel was synthesized by gamma radiation crosslinking for sodium alginate extracted from the marine brown
alga Turbinaria decurrens and acrylic acid. Preparation of the hydrogels involved free radical polymerization of a combination of acrylic acid (w = 0.2) and different contents of sodium alginate (w = 0.05, 0.10, and 0.15) in aqueous solution using gamma rays of a 60Co source at an irradiation dose rate of 1.2 kGy/h. The swelling behavior of the prepared hydrogel was determined by investigating
the swelling time, pH of medium, and alginate content in the hydrogel. The results showed that the hydrogel reached the equilibrium
swelling state in water after 6 h. The hydrogel was found to be pH responsive. The drug loading and in vitro release properties
of the hydrogel were also evaluated using chlortetracycline hydrochloride as the model drug. The adsorption isotherm studies
by batching techniques under the effect of different initial feed concentrations of drug, different pH values, and different
sodium alginate content of the adsorbent hydrogel were investigated. The diffusion of chlortetracycline hydrochloride within
the hydrogel was found to be of non-Fickian character. The kinetic parameters such as the diffusion exponent, diffusion constant,
and diffusion coefficient were also evaluated.
Graphical Abstract
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Content Type Journal Article
Category Original Paper
Pages 1-9
DOI 10.1007/s00706-012-0776-7
Authors
Sahera F. Mohamed, Microbial Biotechnology Department, National Research Center, Dokki, Cairo, Egypt
Ghada A. Mahmoud, National Center for Radiation Research and Technology, Atomic Energy Authority, Cairo, Egypt
Manal F. Abou Taleb, National Center for Radiation Research and Technology, Atomic Energy Authority, Cairo, Egypt
An efficient and convenient preparation of acylals from aldehydes and acetic anhydride, under solvent-free conditions, in
the presence of a silica-supported functional ionic liquid, Si–[SbSipim][PF6], is reported. Si–[SbSipim][PF6] acts as a catalyst and can be recovered and reused four times without apparent loss of its catalytic activity.
Graphical Abstract
Content Type Journal Article
Category Original Paper
Pages 1-3
DOI 10.1007/s00706-012-0777-6
Authors
Li Q. Kang, School of Chemical and Environmental Engineering, Shanghai Institute of Technology, Shanghai, 200235 China
Yue Q. Cai, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237 China
Lin Cheng, School of Chemical and Environmental Engineering, Shanghai Institute of Technology, Shanghai, 200235 China
The changes in the internal part of the activation enthalpy (?∆Hint?) and the activation entropy (?∆S?) in the framework of the isokinetic relationship ?∆Hint? versus (Tiso?Tcomp)?∆S? were explored quantitatively, and the results suggest that it is possible to predict the isokinetic and compensation temperatures,
Tiso and Tcomp, for bimolecular nucleophilic reactions of benzene derivatives in protic and aprotic solvents.
Graphical Abstract
Content Type Journal Article
Category Original Paper
Pages 1-8
DOI 10.1007/s00706-012-0765-x
Authors
Vladislav M. Vlasov, N. N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, Siberian Branch of the Russian Academy of Sciences, Lavrentjev Ave., 9, Novosibirsk, 630090 Russian Federation
We report a facile, efficient procedure for selective oxidation of activated alcohols by use of a novel supported ionic-liquid
catalyst produced by coating polystyrene–TEMPO resin with the ionic liquid [bmim]PF6 and CuCl2. The oxidation affords aldehydes or ketones in excellent yield and with high selectivity. It is worthy of note that the supported
ionic-liquid layer substantially enhances catalytic activity, and the catalyst can easily be recycled.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 1-4
DOI 10.1007/s00706-012-0780-y
Authors
Lin Liu, Jiangsu Marine Resource Development Research Institute, Lianyungang, 222005 China
Dong Liu, Department of Chemical Engineering, Huaihai Institute of Technology, Lianyungang, 222005 China
Zhiwei Xia, Department of Chemical Engineering, Huaihai Institute of Technology, Lianyungang, 222005 China
Jiulin Gao, Department of Chemical Engineering, Huaihai Institute of Technology, Lianyungang, 222005 China
Tianlin Zhang, Jiangsu Marine Resource Development Research Institute, Lianyungang, 222005 China
Juanjuan Ma, Jiangsu Marine Resource Development Research Institute, Lianyungang, 222005 China
Dongen Zhang, Jiangsu Marine Resource Development Research Institute, Lianyungang, 222005 China
Zhiwei Tong, Department of Chemical Engineering, Huaihai Institute of Technology, Lianyungang, 222005 China
We studied the OH and NH dissociation mechanisms of eight tautomers of barbituric acid via excited states. The theoretical
research was performed at the TD DFT level of theory (B3LYP). It was found that all mechanisms pass through the repulsive
1??* excited state whose excited-state reaction paths showed conical intersections S0–S1. Some OH dissociation mechanisms showed barrierless 1??* reaction paths which indicate an ultrafast relaxation of the 1??* excited states to the ground state. The study of the NH dissociation mechanisms revealed that almost all 1??* reaction paths show low energy barriers and minima before the conical intersections S0–S1.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 1-10
DOI 10.1007/s00706-012-0766-9
Authors
Vassil B. Delchev, Department of Physical Chemistry, University of Plovdiv, Tzar Assen 24 Str., Plovdiv, Bulgaria
Iva P. Ivanova, Department of Physical Chemistry, University of Plovdiv, Tzar Assen 24 Str., Plovdiv, Bulgaria
Density functional theory (DFT) calculations at the B3LYP/6-31G* level were performed to investigate the electronic structure
properties of Si-doped boron phosphide nanotubes (BPNTs), which are very important for production of solid-state devices and
other applications, in order to evaluate the influence of Si-doped (4,4) armchair BPNTs. . The chemical shielding isotropic
and anisotropic parameters at the sites of various 11B and 31P atoms, quadrupole coupling constant, and asymmetry parameter at the 11B atom sites in the two Si-doped (4,4) armchair BPNT models were calculated. The calculated results showed that the binding
energies are not attractive and do not characterize a chemisorption process. In comparison to the pristine model, the band
gap of the two Si-doped BPNT models is reduced and increases their electrical conductance. The dipole moment of the two Si-doped
BPNT structures displays notable changes with respect to the pristine model. The NMR and NQR results indicate that in the
SiB and SiP models, the electronic structure properties of the SiB model are more strongly influenced than those of the SiP model, and electronic sites of the B atoms in the SiB model show more changes than the SiP model in the Si doping processes. Decreases in global hardness, energy gap, and ionization potential because of Si doping
processes lower the stability and increase the reactivity of the Si-doped BPNT models.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 1-9
DOI 10.1007/s00706-012-0767-8
Authors
Mohammad T. Baei, Department of Chemistry, Azadshahr Branch, Islamic Azad University, Azadshahr, Golestan, Iran
Ali Ahmadi Peyghan, Young Researchers Club, Islamshahr Branch, Islamic Azad University, Tehran, Iran
Masoumeh Moghimi, Department of Chemistry, Gonbad Kavoos Branch, Islamic Azad University, Gonbad Kavoos, Golestan, Iran
The effect of multiwalled carbon nanotubes (MWCNT) on the polymerization kinetics of bisphenol-A diglycidyl ether/1,4-bis(3-aminopropoxy)butane
was elucidated by means of dynamic and isothermal differential scanning calorimetry. Comparing the results of total reaction
enthalpy and glass-transition temperature measurements for the neat epoxy and epoxy composite containing different mass fractions
of MWCNT allowed the optimum formulation to be found as w(MWCNT) = 0.05. Various kinetic models such as n-th-order, Kamal, and Šesták–Berggren equations were used to estimate the kinetic parameters. We found that the curing reaction
obeys an autocatalytic mechanism. Based on the results obtained from experimental and calculated reaction rates it was recognized
that the model of Šesták–Berggren is the best choice to interpret bisphenol-A diglycidyl ether/1,4-bis(3-aminopropoxy)butane/MWCNT
cure. The dispersion of the nanotubes was subjected to X-ray diffraction measurements, and the results exhibited a well-dispersed
matrix of epoxy and MWCNT with an amorphous structure.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 1-7
DOI 10.1007/s00706-012-0774-9
Authors
Sepide Khostavan, Faculty of Chemistry, University of Mazandaran, P.O. Box 453, Babolsar, Iran
Abdollah Omrani, Faculty of Chemistry, University of Mazandaran, P.O. Box 453, Babolsar, Iran
Abbas Ali Rostami, Faculty of Chemistry, University of Mazandaran, P.O. Box 453, Babolsar, Iran
A series of novel phenylsulfonyl- and 4-aminophenylsulfonyl-carboximidamides were synthesized by condensation of sulfonamides
with heterocyclic methyl carbimidates obtained from heterocyclic carbonitriles and used ‘at its inception.’ The molecular
structure of the obtained compounds is discussed. Compounds possessing heterocyclic systems with a nitrogen atom in the ?
position to the functional group showed a different single-crystal structure than expected. The synthesized derivatives were
evaluated for antimicrobial activities: tuberculostatic, antibacterial, and antifungal.
Graphical Abstract
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Content Type Journal Article
Category Original Paper
Pages 1-9
DOI 10.1007/s00706-012-0769-6
Authors
Katarzyna Gobis, Department of Organic Chemistry, Medical University of Gda?sk, Gda?sk, Poland
Henryk Foks, Department of Organic Chemistry, Medical University of Gda?sk, Gda?sk, Poland
Katarzyna Wi?niewska, Department of Medicinal Microbiology, Chair of Microbiology, Medical University of Gda?sk, Gda?sk, Poland
Maria D?browska-Szponar, Department of Medicinal Microbiology, Chair of Microbiology, Medical University of Gda?sk, Gda?sk, Poland
Ewa Augustynowicz-Kope?, Department of Microbiology, Institute of Tuberculosis and Pulmonary Diseases, Warsaw, Poland
Agnieszka Napiórkowska, Department of Microbiology, Institute of Tuberculosis and Pulmonary Diseases, Warsaw, Poland
Artur Sikorski, Department of Physical Chemistry, University of Gda?sk, Gda?sk, Poland
The surface tension and density of the ternary Bi–Cu–Sn alloys have been measured by the sessile-drop method. Measurements
were carried out for three cross sections with the constant bismuth-to-copper ratios of 2:1, 1:1, and 1:2. The density of
all the investigated alloys decreases with rising temperature. A decrease of the surface tension is also observed when the
temperature increases, except at two compositions on the copper-rich side. An increase of copper content could slightly decrease
the density in the Bi–Cu–Sn system and significantly increase the surface tension as well. Experimental values of the surface
tension were also compared with those calculated from Butler’s equation.
Graphical Abstract
Content Type Journal Article
Category Original Paper
Pages 1-6
DOI 10.1007/s00706-012-0761-1
Authors
Zhongnan Guo, Department of Chemistry, School of Chemical and Biological Engineering, University of Science and Technology Beijing, Xueyuan Road 30, Beijing, 100083 People’s Republic of China
Michael Hindler, Institute of Inorganic Chemistry/Material Chemistry, University of Vienna, Währingerstraße 42, 1090 Vienna, Austria
Wenxia Yuan, Department of Chemistry, School of Chemical and Biological Engineering, University of Science and Technology Beijing, Xueyuan Road 30, Beijing, 100083 People’s Republic of China
Adolf Mikula, Institute of Inorganic Chemistry/Material Chemistry, University of Vienna, Währingerstraße 42, 1090 Vienna, Austria
Copper(II) bis(pentane-2,4-dionato-?2O,O?) compounds with 2-pyridone (1) and 3-hydroxypyridine (2) were prepared by the reaction of bis(pentane-2,4-dionato-?2O,O?)copper(II) with selected ligands. The coordination of Cu(II) in both compounds is square pyramidal with the fifth coordination
site occupied by the carbonyl oxygen atom of the 2-pyridone ligand in 1 and by the nitrogen atom of 3-hydroxypyridine in 2. The X-ray crystallographic studies revealed different crystal aggregation influenced by the ability of the 2-pyridone ligand
to act as a hydrogen bond donor and acceptor, and 3-hydroxypyridine acting only as a hydrogen bond donor. Intermolecular N–H···O
hydrogen bonding forms dimers in 1 and infinite chains in 2. Three-dimensional aggregation is achieved by ?–? interactions and C–H···? (arene) hydrogen bonding.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 1-7
DOI 10.1007/s00706-012-0760-2
Authors
Franc Perdih, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ašker?eva 5, 1000 Ljubljana, Slovenia
Alkaloid-like compounds containing a benzo[c]azepine core structure were successfully prepared in three steps from 5H-dibenzo[a,d]cyclohepten-5-ol via the bridging Ritter reaction. Biological studies of these compounds revealed that some of them are AChE
inhibitors and antimalarial agents.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 955-963
DOI 10.1007/s00706-012-0759-8
Authors
Chulida Hemtasin, Natural Products Research Unit, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen, 40002 Thailand
Alison T. Ung, School of Chemistry and Forensic Science, University of Technology, Broadway, P.O. Box 123, Sydney, NSW 2007, Australia
Somdej Kanokmedhakul, Natural Products Research Unit, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen, 40002 Thailand
Kwanjai Kanokmedhakul, Natural Products Research Unit, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen, 40002 Thailand
Roger Bishop, School of Chemistry, The University of New South Wales, UNSW, Sydney, 2052 Australia
Thanaphat Satraruji, School of Chemistry, University of Wollongong, Wollongong, NSW 2522, Australia
David Bishop, School of Chemistry and Forensic Science, University of Technology, Broadway, P.O. Box 123, Sydney, NSW 2007, Australia
The addition of triphenylphosphine to acetylenedicarboxylic acid in the presence of N–H heterocyclic compounds such as carbazole,
2-indolinone, 2-benzoxazolinone, 2-mercaptobenzoxazole, 2,4-thiazolidinedione, benzimidazole, isatin, or saccharin leads to
stable 1,5-diionic organophosphorus compounds in excellent yields at ambient temperature.
A simple and efficient method to synthesize a variety of tetrahydroquinolinones was successfully achieved by reacting various
?-enaminones with several ?,?-unsaturated aldehydes. This strategy can be viewed as a Brønsted acid-mediated formal [3+3] cycloaddition.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 1-6
DOI 10.1007/s00706-012-0762-0
Authors
Quang Huy To, School of Chemical Engineering, Yeungnam University, Gyeongsan, 712-749 Korea
Yong Rok Lee, School of Chemical Engineering, Yeungnam University, Gyeongsan, 712-749 Korea
Sung Hong Kim, Analysis Research Division, Daegu Center, Korea Basic Science Institute, Daegu, 702-701 Korea
Chiral acyclic and macrocyclic amines derived from trans-1,2-diaminocyclohexane in complexes with diethylzinc efficiently catalyze asymmetric hydrosilylation of aryl–alkyl and aryl–aryl
ketones with enantiomeric excess of the product up to 86 %. A trianglamine ligand with a cyclic structure or the presence
of an additional coordinating group increases the enantioselectivity of the reaction, in comparison with catalysis by a simple
acyclic N,N?-dibenzyl-1,2-diaminocyclohexane ligand. In addition, the effect of the asymmetric activation of the catalyst by a variety
of alcohols and diols is studied.
Graphical Abstract
Content Type Journal Article
Category Original Paper
Pages 1-10
DOI 10.1007/s00706-012-0754-0
Authors
Jadwiga Gajewy, Department of Chemistry, A. Mickiewicz University, 60-780 Poznan, Poland
Jacek Gawronski, Department of Chemistry, A. Mickiewicz University, 60-780 Poznan, Poland
Marcin Kwit, Department of Chemistry, A. Mickiewicz University, 60-780 Poznan, Poland
A facile and efficient one-pot, four-component synthesis of polyhydroquinoline derivatives via the Hantzsch reaction using
Nafion-H® as heterogeneous catalyst in PEG 400–water solvent system is described herein. The present methodology offers several advantages
such as excellent yields, simple procedure, shorter reaction times, and milder conditions with remarkable recyclability.
Graphical Abstract
Content Type Journal Article
Category Original Paper
Pages 1-6
DOI 10.1007/s00706-012-0742-4
Authors
Mazaahir Kidwai, Green Chemistry Research Laboratory, Department of Chemistry, University of Delhi, Delhi, 110007 India
Ritika Chauhan, Green Chemistry Research Laboratory, Department of Chemistry, University of Delhi, Delhi, 110007 India
Divya Bhatnagar, Green Chemistry Research Laboratory, Department of Chemistry, University of Delhi, Delhi, 110007 India
Abhay K. Singh, Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
Biswajit Mishra, Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
Sharmistha Dey, Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
The concentrations of textile dyes in a ternary mixture during biodegradation by the fungus Pleurotus ostreatus were obtained at three temperatures. The reactions followed first-order kinetics. Thermodynamic data were obtained for the
degradation of each dye. High values of ?H‡ show the reaction is enthalpy-driven and positive values of ?S‡ indicate the activated complexes are less structured than the reactants. High values of ?G‡ and Ea explain the low rates of biodegradation of the three dyes.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 1-7
DOI 10.1007/s00706-012-0753-1
Authors
Wagner J. Barreto, Laboratório de Físico Química Ambiental, Departamento de Química, Centro de Ciências Exatas, Universidade Estadual de Londrina, Londrina, 86051-980 Brazil
Suely M. O. Doi, Departamento de Bioquímica e Biotecnologia, Centro de Ciências Exatas, Universidade Estadual de Londrina, Londrina, 86051-980 Brazil
Renata Afonso, Laboratório de Físico Química Ambiental, Departamento de Química, Centro de Ciências Exatas, Universidade Estadual de Londrina, Londrina, 86051-980 Brazil
Nathalia D. Bernardino, Laboratório de Físico Química Ambiental, Departamento de Química, Centro de Ciências Exatas, Universidade Estadual de Londrina, Londrina, 86051-980 Brazil
A simple, inexpensive, environmentally friendly, and efficient route for the synthesis of 3,4-dihydropyrimidin-2(1H)-one derivatives via the one-pot three-component Biginelli reaction using pentafluorophenylammonium triflate (PFPAT) as a
catalyst is described. The organocatalyst is air-stable, cost-effective, easy to handle, and easily removed from the reaction
mixtures.
A new and convenient method is presented for the preparation of mono-3-O-benzoyl-?-cyclodextrin by direct regioselective benzoylation of ?-cyclodextrin using N-benzoylimidazole in carbonate buffer solution. This process involved equilibrium-dependent C2-O-aroyl to C3-O-aroyl group migration to improve the yield.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 1-3
DOI 10.1007/s00706-012-0749-x
Authors
Zhi-zhong Wang, Engineering Research Center for Hui Medicine Modernization, College of Pharmacy, Ningxia Medical University, 750004 Yinchuan, China
Qing Huang, Engineering Research Center for Hui Medicine Modernization, College of Pharmacy, Ningxia Medical University, 750004 Yinchuan, China
Shi-jie Wei, Department of Pharmacy, Ningxia Medical University General Hospital, 750004 Yinchuan, China
Lei Sun, Engineering Research Center for Hui Medicine Modernization, College of Pharmacy, Ningxia Medical University, 750004 Yinchuan, China
Jing Chen, Engineering Research Center for Hui Medicine Modernization, College of Pharmacy, Ningxia Medical University, 750004 Yinchuan, China
Quantum mechanical density functional theory (DFT) calculations were used to derive the most probable structures of the bambus[6]uril·OCN? and bambus[6]uril·SCN? anionic complex species. In these two C3 symmetric complexes, each of the two considered anions, included in the macrocyclic cavity, is bound by 12 weak hydrogen
bonds between methine hydrogen atoms on the convex face of glycoluril units and the respective anion.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 1-4
DOI 10.1007/s00706-012-0748-y
Authors
Petr Toman, Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
Emanuel Makrlík, Faculty of Environmental Sciences, Czech University of Life Sciences, Prague, Czech Republic
Petr Va?ura, Department of Analytical Chemistry, Institute of Chemical Technology, Prague, Czech Republic
Palladium-catalyzed reactions are key steps for the formation of carbon–carbon bonds in modern synthetic chemistry and among
these reactions few have influenced organic synthesis as greatly as the Suzuki–Miyaura reaction which was first reported in
1979. This review highlights recent and major developments of this approach in intramolecular cyclization and heterocyclization
reactions.
Graphical abstract
Content Type Journal Article
Category Review
Pages 861-880
DOI 10.1007/s00706-012-0746-0
Authors
Majid M. Heravi, Department of Chemistry, School of Science, Azzahra University, Vanak, Tehran, Iran
Elaheh Hashemi, Department of Chemistry, School of Science, Azzahra University, Vanak, Tehran, Iran
From extraction experiments in the two-phase water/nitrobenzene system and ?-activity measurements, the stability constant
of the beauvericin ·H3O+ complex species dissolved in nitrobenzene saturated with water was determined. By using quantum-mechanical density functional
level of theory (DFT) calculations, the most probable structure of this complex was derived.
Graphical Abstract
Content Type Journal Article
Category Original Paper
Pages 891-894
DOI 10.1007/s00706-012-0747-z
Authors
Emanuel Makrlík, Faculty of Environmental Sciences, Czech University of Life Sciences, Prague, Czech Republic
Petr Toman, Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
Petr Va?ura, Department of Analytical Chemistry, Institute of Chemical Technology, Prague, Czech Republic
The reactions of diorganotin(IV) dichlorides SnR2Cl2 (R = Me, n-Bu) with a series of ligands having N, P, or O donor atoms have been investigated. The reaction of SnR2Cl2 (R = Me, n-Bu) with the bidentate chelating pyridyl ligands of phendione (1,10-phenanthroline-5,6-dione) and ndppz (11-nitrodipyrido[3,2-a:2?,3?-c]phenazine) affords new hexa-coordinated 1:1 adducts with general formula SnR2Cl2L (R = Me, n-Bu; L = phendione, ndppz). On the other hand, SnMe2Cl2 reacted with xantphos [9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene] to yield the hexa-coordinated 1:2 adduct [SnMe2Cl2(xantphos)2] in the solid state. However, it dissociates in solution to give the penta-coordinated 1:1 complex [SnMe2Cl2(xantphos)]. Notably, the analogous n-Bu derivative does not react, even under forcing conditions. Finally, the tin(IV) compounds SnR2Cl2 (R = Me, n-Bu) react with dppap [2-(diphenylphosphinoamino)pyridine] to give the penta-coordinated 1:1 adducts [SnR2Cl2(dppap)] (R = Me, n-Bu). The resulting complexes have been characterized by nuclear magnetic resonance (NMR) spectroscopy and elemental analysis.
The X-ray crystal structure determination of [SnMe2Cl2(phendione)] reveals that the compound crystallized with two independent molecules in the asymmetric unit with a trans-[SnMe2] configuration.
Graphical Abstract
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Content Type Journal Article
Category Original Paper
Pages 1-8
DOI 10.1007/s00706-012-0733-5
Authors
B. Z. Momeni, Department of Chemistry, K.N. Toosi University of Technology, P.O. Box 16315-1618, 15418 Tehran, Iran
R. Kia, X-ray Crystallography Lab, Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran, Iran
S. Ghanbarzadeh, Department of Chemistry, K.N. Toosi University of Technology, P.O. Box 16315-1618, 15418 Tehran, Iran
Densities ? and dynamic viscosities ? of ternary mixtures consisting of vinyl acetate + trichloroethylene + tetrachloroethylene
and related binary mixtures have been measured over the whole composition range at T = 298.15 K. The data obtained were used to calculate excess molar volumes
V\textm\textE
, excess partial molar volumes
V\textm,i\textE
, limiting excess partial molar volumes
V\textm,i\textE,¥
, and viscosity deviations ∆? of binary and ternary mixtures. Data of excess molar volumes and viscosity deviations of binary
systems were fitted to the Redlich–Kister and Cibulka equations, respectively. Viscosities of the binary mixtures have been
correlated by means of several semi-empirical equations to determine the fitting parameters and the standard deviations. The
experimental data are analyzed to discuss the nature and strength of intermolecular interactions in these mixtures.
Graphical Abstract
Content Type Journal Article
Category Original Paper
Pages 1-7
DOI 10.1007/s00706-012-0745-1
Authors
Hossein Iloukhani, Department of Physical Chemistry, Faculty of Chemistry, Bu-Ali Sina University, Hamedan, Iran
Ali Sadeghi, Department of Physical Chemistry, Faculty of Chemistry, Bu-Ali Sina University, Hamedan, Iran
Hosseinali Zarei, Department of Physical Chemistry, Faculty of Chemistry, Bu-Ali Sina University, Hamedan, Iran
Twelve new derivatives of 5-amino-7-aryl-6-cyano-4H-pyrano[3,2-b]pyrrole were prepared by one-pot acid-catalyzed cyclocondensation reaction of 3-hydroxypyrrole, malononitrile, and various
aldehydes in the presence of the silica-supported ionic liquid 1-methyl-3-(triethoxysilylpropyl)imidazolium hydrogen sulfate
as catalyst. The reaction efficiencies were enhanced by moderate electron-withdrawing groups, such Cl and Br, on benzaldehyde,
but decreased as substituents became more electron-withdrawing. Among the solvents and catalysts screened for the model reaction,
acetonitrile and the silica-supported hydrogen sulfate ionic liquid were found to be the best choices.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 1-7
DOI 10.1007/s00706-012-0744-2
Authors
Reza Sandaroos, Department of Chemistry, Faculty of Science, University of Birjand, Birjand, Iran
Saman Damavandi, Department of Chemistry, Sarvestan Branch, Islamic Azad University, Sarvestan, Iran
Mehri Salimi, Department of Chemistry, Faculty of Science, University of Birjand, Birjand, Iran
Upon comparative NMR spectroscopy studies, the isomerization of newly disclosed dichloro [?2(C,O)-2-(N-propylaminocarbonyl)benzylidene][1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene]ruthenium from trans-dichloro configuration (SPY-5-31) to its thermodynamically more favored cis-dichloro derivative (with SPY-5-34 stereochemistry) was found to proceed via dissociation of one chloride ligand to form an intermediate cationic species.
Furthermore, the performance of the trans- and the cis-dichloro derivatives as catalysts in ring-closing metathesis and as initiators in ring-opening metathesis polymerization
was studied.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 901-908
DOI 10.1007/s00706-012-0740-6
Authors
Anita Leitgeb, Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
Kurt Mereiter, Institute of Chemical Technology and Analytics, Vienna University of Technology, Getreidemarkt 9, 1060 Vienna, Austria
Christian Slugovc, Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
The behavior of the cyano radical (·C?N) adsorbed on the external surface of a (6,0) zigzag single-walled carbon nanotube was studied by using density functional calculations. Geometry optimizations were carried out
at the B3LYP/6-31G* level of theory using the Gaussian 03 suite of programs. Our results show that the pristine carbon nanotubes
can detect a ·CN. The calculated binding energy of the ·CN-attached (6,0) single-walled carbon nanotube indicates that the
·CN can be best adsorbed at a carbon site in a C-down orientation (binding energy ?356.5 kJ mol?1) and can thus be used in detection and storage of this species. The density of the state spectra, electron density plot,
and HOMO and LUMO for the adsorbed species characterize it as a chemisorption process. The increase in global hardness, energy
gap, and ionization potential because of the ·CN functional group point to an increase of stability and decrease in reactivity
and electrophilicity of the ·CN-attached (6,0) CNT model. In addition, the ?N value for the ·CN/CNT complex is positive, indicating that the ·CN acts as an electron acceptor.
Graphical Abstract
Content Type Journal Article
Category Original Paper
Pages 1-8
DOI 10.1007/s00706-012-0739-z
Authors
Mohammad T. Baei, Department of Chemistry, Azadshahr Branch, Islamic Azad University, Azadshahr, Golestan, Iran
Ali Ahmadi Peyghan, Young Researchers Club, Islamshahr Branch, Islamic Azad University, Tehran, Iran
Masoumeh Moghimi, Department of Chemistry, Gonbad Kavoos Branch, Islamic Azad University, Gonbad Kavoos, Golestan, Iran
The reactions of 4-(p-nitrobenzyl)pyridine (a trap for alkylating agents with nucleophilicity similar to that of DNA) with the vinyl compounds
acrylonitrile, acrylamide, acrylic acid, and acrolein, which can act as alkylating agents of DNA, were investigated. The following
conclusions were drawn: (1) vinyl compounds show an alkylating capacity on 4-(p-nitrobenzyl)pyridine. The sequence of the alkylating potential was found to be acrylonitrile > acrylamide > acrylic acid > acrolein
(alkylation with acrolein was not observed after 3 weeks). The formation of adducts with acrylonitrile was approximately 10-
and 100-fold faster than with acrylamide and acrylic acid, respectively, which is consistent with its highly carcinogenic
and mutagenic activity. (2) 4-(p-Nitrobenzyl)pyridine alkylation reactions by vinyl compounds occur through an enthalpy-controlled Michael addition mechanism.
The values for the free energy of activation for these reactions with 4-(p-nitrobenzyl)pyridine were: ?‡G° (37 °C) acrylonitrile, 98 ± 1 kJ mol?1; acrylamide, 105 ± 2 kJ mol?1; acrylic acid, 109 ± 1 kJ mol?1. (3) Application of Hammett treatment to the kinetic results revealed that these alkylation reactions occur through nucleophilic
attack, being moderately accelerated by electron-withdrawing groups.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 723-727
DOI 10.1007/s00706-012-0736-2
Authors
Isaac F. Céspedes-Camacho, Departamento de Química física, Universidad de Salamanca, Plaza de los Caídos 1-5, 37008 Salamanca, Spain
José A. Manso, Departamento de Química física, Universidad de Salamanca, Plaza de los Caídos 1-5, 37008 Salamanca, Spain
Mario González-Jiménez, Departamento de Química física, Universidad de Salamanca, Plaza de los Caídos 1-5, 37008 Salamanca, Spain
Emilio Calle, Departamento de Química física, Universidad de Salamanca, Plaza de los Caídos 1-5, 37008 Salamanca, Spain
Julio Casado, Departamento de Química física, Universidad de Salamanca, Plaza de los Caídos 1-5, 37008 Salamanca, Spain
We performed a computational study (density functional theory, DFT) on the adsorption of the nitrate ion on single-walled
carbon nanotubes in both the gas phase and aqueous medium. The nitrate ion adsorption is energetically favorable in the gas
phase with a large adsorption energy of ?1.30 eV, but it is endothermic in solvent medium. The electronic properties analysis
reveals that both solvent and chemisorbed NO3? significantly change the highest occupied molecular orbital (HOMO)/lowest unoccupied molecular orbital (LUMO) energy gap
of the nanotubes (by about 31 %). The present results indicate that the HOMO level of NO3? in solvent is much more stable than that in gas phase. It suggests that this phenomenon in addition to the solvent molecules
(covering the ions) effectively prevents the adsorption of the NO3? ion on carbon nanotubes.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 1-4
DOI 10.1007/s00706-012-0738-0
Authors
Javad Beheshtian, Department of Chemistry, Shahid Rajaee Teacher Training University, P.O. Box 16875-163, Tehran, Iran
Ali Ahmadi Peyghan, Young Researchers Club, Islamic Azad University, Islamshahr Branch, Tehran, Iran
Two series of novel 4-chloro-2-(benzylthio)-5-(1,3,4-oxadiazol-2-yl)benzenesulfonamides and their N-aroyl derivatives have been synthesized and evaluated for in vitro anticancer activity against the full NCI-60 cell line
panel. Most of the compounds exhibited antiproliferative activity. Among them a compound bearing an N-(thien-2-ylcarbonyl) moiety showed broad-spectrum activity with 50% growth inhibition (GI50) values in the range of 2.02–7.82 ?M over 50 cell lines.
Graphical abstract
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Content Type Journal Article
Category Original Paper
Pages 975-984
DOI 10.1007/s00706-012-0732-6
Authors
Kamil Bro?ewicz, Department of Organic Chemistry, Medical University of Gda?sk, Al. Gen. J. Hallera 107, 80-416 Gda?sk, Poland
Jaros?aw S?awi?ski, Department of Organic Chemistry, Medical University of Gda?sk, Al. Gen. J. Hallera 107, 80-416 Gda?sk, Poland
A fast, one pot method with excellent yield has been developed for preparation of 1,4,5-trisubstituted pyrazoles. Treatment
of ?-dicarbonyl compounds with N,N-dimethylformamide dimethylacetal and hydrazine derivatives afforded immediately the desired pyrazoles under solvent-free
conditions in the absence of catalyst.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 947-950
DOI 10.1007/s00706-012-0721-9
Authors
Heshmatollah Alinezhad, Faculty of Chemistry, University of Mazandaran, Babolsar, Iran
Mahmood Tajbakhsh, Faculty of Chemistry, University of Mazandaran, Babolsar, Iran
Mahboobeh Zare, Faculty of Chemistry, University of Mazandaran, Babolsar, Iran
The electrophilicity of (E)-2-aryl-1-cyano-1-nitroethenes is not sufficient to induce a zwitterionic course of their [4+2] cycloaddition to cyclopentadiene.
The one-step mechanism of these reactions is indicated by the activation parameters, and the substituent and solvent effects
on the reaction.
Graphical Abstract
Content Type Journal Article
Category Original Paper
Pages 895-899
DOI 10.1007/s00706-012-0735-3
Authors
Radomir Jasi?ski, Institute of Organic Chemistry and Technology, Cracow University of Technology, Warszawska 24, 31-155 Cracow, Poland
Magdalena Kwiatkowska, Institute of Organic Chemistry and Technology, Cracow University of Technology, Warszawska 24, 31-155 Cracow, Poland
Andrzej Bara?ski, Institute of Organic Chemistry and Technology, Cracow University of Technology, Warszawska 24, 31-155 Cracow, Poland
Ethyl vinyl ether was found to be an appropriate synthetic equivalent of acetylene for a set of Diels–Alder reactions with
fused pyran-2-ones that yield fused carbocyclic systems. Transformations were conducted under microwave irradiation with DABCO
(as a catalyst for the elimination of ethanol) and with n-butanol as the additive. A single-crystal X-ray diffraction structure is presented for N-(5,6,7,8-tetrahydro-6-methyl-8-oxonaphthalen-2-yl)benzamide.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 771-777
DOI 10.1007/s00706-012-0734-4
Authors
Amadej Juranovi?, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ašker?eva 5, 1000 Ljubljana, Slovenia
Krištof Kranjc, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ašker?eva 5, 1000 Ljubljana, Slovenia
Slovenko Polanc, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ašker?eva 5, 1000 Ljubljana, Slovenia
Franc Perdih, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ašker?eva 5, 1000 Ljubljana, Slovenia
Marijan Ko?evar, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ašker?eva 5, 1000 Ljubljana, Slovenia
Mixed-ligand Cu(II), Ni(II), Co(II), and Zn(II) complexes using a tryptophan-derived Schiff base (obtained by the condensation
of tryptophan and benzaldehyde) as the primary ligand and 1,10-phenanthroline as the co-ligand were synthesized and characterized
analytically and spectroscopically by performing elemental analyses, magnetic susceptibility and molar conductance measurements,
UV-Vis, IR, NMR, and FAB-MS. The binding properties of metal complexes with DNA were investigated by electronic absorption
spectroscopy, cyclic voltammetry, and by performing viscosity measurements, and the results showed that these complexes have
the ability to interact with DNA via an intercalative mode. The DNA cleavage efficiencies of these complexes with pUC19 DNA
were investigated by gel electrophoresis. The complexes were found to promote the cleavage of pUC19 DNA from the supercoiled
form I to the open circular form II and the linear form III in the presence of ascorbic acid. Finally, the in vitro antibacterial
activities of the Schiff base and its mixed-ligand metal complexes were screened against the bacteria Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, and Salmonella typhi. The antibacterial screening data revealed that the complexes show growth inhibitory activity against bacteria.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 1-9
DOI 10.1007/s00706-012-0718-4
Authors
Natarajan Raman, Research Department of Chemistry, VHNSN College, Virudhunagar, 626 001 India
Sivasangu Sobha, Research Department of Chemistry, VHNSN College, Virudhunagar, 626 001 India
Muthusamy Selvaganapathy, Research Department of Chemistry, VHNSN College, Virudhunagar, 626 001 India
In this work, the effect of surface roughness and cleaning procedures on reactivity during priming with hexamethyldisilazane
is described for four silicon substrates frequently used in semiconductor technology, namely thermally grown SiO2, argon implanted tetraorthosilicate SiO2, polysilicon, and amorphous silicon. Surface energy and roughness were determined by static contact angle measurements and
atomic force microscopy. The surface roughness of the silicon substrates increased in the order: thermally grown SiO2, argon implanted tetraorthosilicate SiO2, polysilicon, and amorphous silicon. It was found not to be substantially affected by standard cleaning procedures. The surface
energy of all silicon samples decreased with increasing hexamethyldisilazane vapor exposure at 90 °C, and the extent of the
decrease corresponded to the surface roughness. Furthermore, a promoting effect on the silylation reaction by an argon implantation
process was determined. A correlation between the surface morphology of different silicon materials and reactivity in the
silylation reaction with hexamethyldisilazane could be established.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 717-722
DOI 10.1007/s00706-012-0730-8
Authors
Thomas Bodner, Polymer Competence Center Leoben GmbH PCCL, Roseggerstrasse 12, 8700 Leoben, Austria
Andreas Behrendt, Infineon Technologies Austria AG, Siemensstrasse 2, 9500 Villach, Austria
Emil Prax, Infineon Technologies Austria AG, Siemensstrasse 2, 9500 Villach, Austria
Frank Wiesbrock, Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, 8010 Graz, Austria
A new strategy which uses cheap K3PO4 as a very effective catalyst has been developed for synthesis of ?-amino ketones by one-pot reaction of an aryl aldehyde,
acetophenone derivative, and amine in EtOH at room temperature.
Graphical Abstract
Content Type Journal Article
Category Original Paper
Pages 1-4
DOI 10.1007/s00706-012-0729-1
Authors
Barahman Movassagh, Department of Chemistry, K. N. Toosi University of Technology, P. O. Box 16315-1618, Tehran, Iran
Sakineh Khosousi, Department of Chemistry, K. N. Toosi University of Technology, P. O. Box 16315-1618, Tehran, Iran
Amberlyst 15 efficiently catalyzed the electrophilic substitution reaction of indoles with isatin derivatives to afford 3,3-di(indolyl)oxindoles
in water. An important feature of this protocol is the reaction of 3-methyl-1H-indole with isatins to give the corresponding 3,3-diaryloxindole derivatives in high yields. The catalyst exhibited remarkable
reusable activity.
Graphical Abstract
.
Content Type Journal Article
Category Original Paper
Pages 1-4
DOI 10.1007/s00706-012-0723-7
Authors
Yaghoub Sarrafi, Division of Organic Chemistry, Faculty of Chemistry, University of Mazandaran, 47416 Babolsar, Iran
Kamal Alimohammadi, Tarbiat moallem of Dr. Shariaty, University of Payambare Aazam, Sari, Iran
Marzieh Sadatshahabi, Division of Organic Chemistry, Faculty of Chemistry, University of Mazandaran, 47416 Babolsar, Iran
Nasibeh Norozipoor, Division of Organic Chemistry, Faculty of Chemistry, University of Mazandaran, 47416 Babolsar, Iran
?-Aminoisobutanoic acid and some representatives of cyclic ?-amino acids were converted to corresponding 1-phthalimido- and N-trifluoroacylated acid chlorides. Treatment of 2-(1H-benzimidazol-2-yl)acetonitrile with 1-phthalimidoacid chlorides in DMF unexpectedly gave 2-(1H-benzimidazol-2-yl)-3-(dimethylamino)-2-propenenitrile. On the other hand, the reaction of hetarylacetonitriles with N-trifluoroacylated acid chlorides gave the desired (3-cyano-2-oxo-3-hetarylpropyl)-2,2,2-trifluoroacetamides that upon detrifluoroacetylation
provided the target 2-amino-3-hetarylpyrrolin-4-ones. The acylation of benzoimidazolylaminopyrrolinones by benzoyl chloride
leads to formation of 3-benzoyl-2,3-dihydro-5-phenyl-1H-benzo[4,5]imidazo[1,2-c]pyrrolo[3,2-e]pyrimidin-1-ones.
Graphical Abstract
Content Type Journal Article
Category Original Paper
Pages 779-789
DOI 10.1007/s00706-012-0727-3
Authors
Alexey V. Dobrydnev, Chemistry Department, Kiev National Taras Shevchenko University, Vladimirskaya Street, 60, Kiev, 01033 Ukraine
Tatyana A. Volovnenko, Chemistry Department, Kiev National Taras Shevchenko University, Vladimirskaya Street, 60, Kiev, 01033 Ukraine
Yulian M. Volovenko, Chemistry Department, Kiev National Taras Shevchenko University, Vladimirskaya Street, 60, Kiev, 01033 Ukraine
Gennady V. Palamarchuk, Division of Functional Materials Chemistry, SSI “Institute for Single Crystals” National Academy of Science of Ukraine, Lenina Avenue, 60, Kharkiv, 61001 Ukraine
Oleg V. Shishkin, Department of Inorganic Chemistry, V.N. Karazin Kharkiv National University, Svobody Square, 4, Kharkiv, 61202 Ukraine
Novel isoxazoline derivatives bearing a 1,2,4-triazole moiety have been synthesized starting from 2-bromo-1-phenylethanone.
Chalcones were obtained by aldol condensation of 1-phenyl-2-(1H-1,2,4-triazol-1-yl)ethanone and 4-substituted benzaldehydes using piperidine as catalyst. Finally, 1,3-dipolar cycloaddition
of the chalcones and a variety of aldoximes in the presence of chloramine-T afforded the title compounds. The structural identities
of these compounds were confirmed on the basis of IR, NMR, mass spectral, and elemental analysis data and by X-ray analysis
of a typical example of the new class of isoxazoline analogs.
Graphical Abstract
Content Type Journal Article
Category Original Paper
Pages 1-6
DOI 10.1007/s00706-012-0722-8
Authors
Zhi-Qiang Dong, College of Material and Chemical Engineering, Hangzhou Normal University, Hangzhou, 310036 Zhejiang, People’s Republic of China
Fang-Ming Liu, College of Material and Chemical Engineering, Hangzhou Normal University, Hangzhou, 310036 Zhejiang, People’s Republic of China
Sheng-Qin Chen, College of Material and Chemical Engineering, Hangzhou Normal University, Hangzhou, 310036 Zhejiang, People’s Republic of China
We investigated the degradation of chlorinated phenols under reductive electron transfer reaction conditions. Although Li
and Na metal proved useless, activated forms of these metals, either their soluble naphthalene radical anions or 1,2-diarylethane
dianions, promoted the degradation of the starting materials to various extents. Additionally, efficient dehalogenation of
the sodium salts of several mono-, di-, and tri-chlorophenols was obtained by their reduction with an excess of Na metal and
a catalytic amount of naphthalene.
Graphical Abstract
.
Content Type Journal Article
Category Original Paper
Pages 601-605
DOI 10.1007/s00706-012-0726-4
Authors
Ugo Azzena, Dipartimento di Chimica, Università di Sassari, via Vienna 2, 07100 Sassari, Italy
Giovanna Dettori, Dipartimento di Chimica, Università di Sassari, via Vienna 2, 07100 Sassari, Italy
Luisa Pisano, Dipartimento di Chimica, Università di Sassari, via Vienna 2, 07100 Sassari, Italy
Mario Pittalis, Dipartimento di Chimica, Università di Sassari, via Vienna 2, 07100 Sassari, Italy
Giuseppe Mangano, Dipartimento di Scienze del Farmaco, Università di Sassari, via Muroni, 23/A, 07100 Sassari, Italy
Giacomo Petretto, Dipartimento di Scienze del Farmaco, Università di Sassari, via Muroni, 23/A, 07100 Sassari, Italy
Giorgio Pintore, Dipartimento di Scienze del Farmaco, Università di Sassari, via Muroni, 23/A, 07100 Sassari, Italy
From extraction experiments in the two-phase water–nitrobenzene system and ?-activity measurements, the stability constant
of the dibenzo-30-crown-10·NH4+ complex species dissolved in nitrobenzene saturated with water was determined. By use of quantum-mechanical calculations,
the most probable structures of this complex species were predicted.
Graphical abstract
.
Content Type Journal Article
Category Original Paper
Pages 711-715
DOI 10.1007/s00706-012-0719-3
Authors
Emanuel Makrlík, Faculty of Environmental Sciences, Czech University of Life Sciences, Prague, Czech Republic
Petr Toman, Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
Petr Va?ura, Department of Analytical Chemistry, Institute of Chemical Technology, Prague, Czech Republic
1-Aryl-N,N-dimethyl-1H-naphtho[1,2-e][1,3]oxazine-3-amine derivatives were synthesized in moderate to high yields using a novel, facile, and one-pot condensation
of N,N,N?,N?-tetramethylguanidine, aromatic aldehydes, and ?-naphthol under microwave-assisted conditions.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 1-4
DOI 10.1007/s00706-011-0716-y
Authors
Javad Azizian, Department of Chemistry, Science and Research Branch, Islamic Azad University, Ponak, Tehran, Iran
Khadijeh Yadollahzadeh, Department of Chemistry, Aliabad Katoul Branch, Islamic Azad University, Aliabad Katoul, Iran
Akram Sadat Delbari, Department of Chemistry, Islam Shahr Branch, Islamic Azad University, Tehran, Iran
Mohammad Mehdi Ghanbari, Young Researchers Club, Sarvestan Branch, Islamic Azad University, Sarvestan, Iran
The inhibition effect of sildenafil citrate (Viagra) on the corrosion of carbon steel in 1 M HCl was studied by weight loss,
polarization, electrochemical impedance spectroscopy, and UV–Vis spectrophotometry. The results showed that sildenafil citrate
is a good corrosion inhibitor for carbon steel in acidic media and acts as mixed type (cathodic/anodic) inhibitor. The adsorption
of the inhibitor was well described by the Langmuir adsorption isotherm. Some thermodynamic parameters such as adsorption
heat, adsorption entropy, and adsorption free energy were calculated. Kinetic parameters such as the apparent activation energy
and pre-exponential factor were calculated and discussed.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 1-9
DOI 10.1007/s00706-011-0710-4
Authors
M. Sobhi, Chemistry Department, Faculty of Science, Benha University, Benha, Egypt
M. Abdallah, Chemistry Department, Faculty of Science, Benha University, Benha, Egypt
K. S. Khairou, Chemistry Department, Faculty of Applied Science, Umm Al-Qur University, Makkah Al Mukarramha, Saudi Arabia
The nucleobases cytosine, uracil, and thymine and their H-bonded complexes with one molecule of water were studied at the
CC2/aug-cc-pVDZ level of theory. The excited-state deactivation mechanisms through the conical intersections S0/S1 were investigated. It was found that the 1??* excited states of cytosine, the hydroxy tautomer of uracil, and the hydroxy tautomer of thymine relax non-radiatively to
the ground state S0. However, only monohydrated and anhydrous thymine do not have energy barriers of the 1??* excited-state reaction paths. The photophysical reaction of monohydrated thymine could proceed in two directions on the S0 surface.
Graphical abstract
.
Content Type Journal Article
Category Original Paper
Pages 763-770
DOI 10.1007/s00706-012-0720-x
Authors
Ivan G. Shterev, Department of Inorganic and Physical Chemistry, University of Food Technologies, 4002 Plovdiv, Bulgaria
Vassil B. Delchev, Department of Physical Chemistry, University of Plovdiv, 4000 Plovdiv, Bulgaria
The stability constant of a hexaarylbenzene-based receptor–protonated 1,4-diazabicyclo[2.2.2]octane complex dissolved in nitrobenzene
saturated with water was determined from extraction experiments in the two-phase water/nitrobenzene system and ?-activity measurements. Using quantum-mechanical calculations (DFT), the most probable structure of this complex was derived.
Graphical Abstract
Content Type Journal Article
Category Original Paper
Pages 563-568
DOI 10.1007/s00706-011-0714-0
Authors
Emanuel Makrlík, Faculty of Environmental Sciences, Czech University of Life Sciences, Prague, Czech Republic
Petr Toman, Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Prague, Czech Republic
Petr Va?ura, Department of Analytical Chemistry, Institute of Chemical Technology, Prague, Czech Republic
Rajendra Rathore, Department of Chemistry, Marquette University, Milwaukee, WI, USA
An efficient synthesis of various tetraarylated imidazoles using anhydrous FePO4 as a catalyst by four-component condensation of benzil (or benzoin), aldehydes, amines, and ammonium acetate in refluxing
ethanol is described.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 1-4
DOI 10.1007/s00706-012-0724-6
Authors
Farahnaz K. Behbahani, Department of Chemistry, Karaj Branch, Islamic Azad University, Karaj, Iran
Talayeh Yektanezhad, Department of Chemistry, Karaj Branch, Islamic Azad University, Karaj, Iran
Antimicrobial peptides are an important class of therapeutic agents used against a wide range of pathogens such as gram-negative
and -positive bacteria, fungi, and viruses. The minimal inhibitory concentration at the level of the pathogen membrane is
a major determinant of the pharmacokinetic behavior and, consequently, it can affect their antimicrobial activity. Here we
generated quantitative structure-activity relationship models (3D-QSAR—comparative molecular field analysis/comparative molecular
similarity indices analysis) using a database of 33 mastoparan analogs, antimicrobial peptides with known experimental activity,
and further used these models to predict the minimal inhibitory concentration for 18 new mastoparan analogs, obtained by computational
mutagenesis. We discuss two options for structural alignment of mastoparan analogs: superposition of C? trace atoms or superposition of all backbone atoms. Significant values of the cross-validated correlation q2 (higher than 0.60) and the fitted correlation r2 (higher than 0.90) of our models indicate that they are reliable enough for activity prediction in the case of new derivatives.
This allows us to identify compounds with possibly enhanced antimicrobial activity against Bacillus subtilis, which are suggested for further experimental studies.
Graphical Abstract
Content Type Journal Article
Category Original Paper
Pages 535-543
DOI 10.1007/s00706-011-0713-1
Authors
Speranta Avram, Faculty of Biology, Anatomy, Animal Physiology and Biophysics Department, University of Bucharest, 91-95th Spl. Independentei, 076201 Bucharest, Romania
Dan Mihailescu, Faculty of Biology, Anatomy, Animal Physiology and Biophysics Department, University of Bucharest, 91-95th Spl. Independentei, 076201 Bucharest, Romania
Florin Borcan, Pharmaceutical Chemistry Department, Faculty of Pharmacy, “Victor Babes” University of Medicine and Pharmacy, 2nd E. Murgu Sq., 300041 Timisoara, Romania
Adina-Luminita Milac, Institute of Biochemistry of the Romanian Academy, 296th Spl. Independentei, 060031 Bucharest, Romania
The retention behaviour of semicarbazides and their cyclic analogues 1,2,4-triazol-3-ones, has been investigated by RP-8,
RP-18 and IAM HPLC. The structures of new derivatives were proved by elemental analyses, IR, 1H NMR and 13C NMR spectroscopy. The compounds showed regular retention behaviour in three chromatographic systems; their log k values decreased linearly with the increasing concentration of an organic modifier in the mobile phase. The ratio of the
intercept (log kw) to the slope of compounds is constant and the same for both groups of compounds on C18 and IAM stationary phases. Differences
between log kw values from the octadecyl stationary phase of corresponding cyclic and linear derivatives are constant, and they are related
to the mechanism of synthesis of 1,2,4-triazol-3-ones from linear substrate semicarbazides, which was confirmed by modelling
studies. Good correlations between log kw parameters obtained by RP-8 or RP-18 and determined by the computational approach log P were found.
Graphical Abstract
Content Type Journal Article
Category Original Paper
Pages 657-667
DOI 10.1007/s00706-011-0715-z
Authors
Monika Pitucha, Department of Organic Chemistry, Medical University of Lublin, Lublin, Poland
Joanna Matysiak, Department of Chemistry, University of Life Sciences in Lublin, Lublin, Poland
Bogdan Senczyna, Department of Chemistry, University of Life Sciences in Lublin, Lublin, Poland
A variation of the London equation was derived for liquids. The function S2 = IRm2/Vb2 is proportional to the cohesive energy, and also to the boiling point, Tb. In the current article the function S2 is plotted against boiling temperatures for four groups of substances: the rare gases, group 18, the group 14 tetrahydrides,
some diatomic substances, and the group 14 symmetrical tetrahalides. Linear relationships were then drawn via closest fit.
The line at the lowest boiling points contained the rare gases and the group 14 tetrahydrides. Of note, it is known that the
rare gases are spherical. From this assertion we infer through empirical reasoning that central atoms with their substituent
bulk deviate from the overall spherical shape of rare gases and may encounter greater rotational barriers. This short paper
does not attempt to calculate such values quantitatively, but derives empirical evidence to such by the function S2 versus the boiling point plot. We surmise that the group 14 tetrahydrides are also close to spherical in nature. This assertion
is supported by a neutron study and electron density maps. The diatomic molecules are also found to be close to spherical,
which may explain their low boiling points. However, the group 14 tetrahalides boil much higher (as much as 160 K) than expected
from London forces. It is suggested here that restricted rotation of the individual neighboring molecules occurs because of
the protruding halogen atoms on a central atom. Rotation is therefore interfered with by neighboring molecules. In addition
to cohesive energy of molecules, there is an amount of energy added to place the molecules into free rotation within a gas.
Graphical abstract
Content Type Journal Article
Category Original Paper
Pages 557-561
DOI 10.1007/s00706-011-0712-2
Authors
R. Thomas Myers, Department of Chemistry, Kent State University, 214 Williams Hall, Kent, OH 44240, USA
Donald E. Pryor, Department of Chemistry, Kent State University, 214 Williams Hall, Kent, OH 44240, USA
A newly arising challenge in the field of nanoparticle research concerns the control and the understanding of the interparticle
interactions and interparticle properties. This should allow the development of materials based on nanoparticle assemblies
which represents a great opportunity to exploit nanoparticle collective properties. Although some nanoparticle networks have
been reported, few works are addressing the highly exciting problem of forming bis-nanoparticle assemblies in which two different
types of nanoparticles are present. In this article we report an original synthesis pathway for the formation of an ionic
bis-nanoparticle network, silica/silver, based on the formation of an imidazolium bridging unit. The reaction used for the
formation of the bridging imidazolium can be considered as click-like chemistry. The synthesis of the metal/metal oxide hybrid
composite material starts from the formation of a metal oxide nanoparticle modified with an imidazole ligand. This composite
formation is therefore very general and could be extended to other metal/metal oxide composites.
Graphical Abstract
.
Content Type Journal Article
Category Original Paper
Pages 519-525
DOI 10.1007/s00706-011-0709-x
Authors
Marie-Alexandra Neouze, Institute of Materials Chemistry, Vienna University of Technology, Vienna, Austria
Marco Litschauer, Institute of Materials Chemistry, Vienna University of Technology, Vienna, Austria
Michael Puchberger, Institute of Materials Chemistry, Vienna University of Technology, Vienna, Austria
Johannes Bernardi, Transmission Electron Microscopy Centre, USTEM, Vienna University of Technology, Vienna, Austria
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