Vol 5, No 1 (2014)

March 2014

Table of Contents


Hakan Arslan
DOI 10.5155/eurjchem.5.1.i-i.1017
Editorial Board
Hakan Arslan
DOI 10.5155/eurjchem.5.1.ii-ix.1018
Graphical Contents

Research Article

Judith Amador-Hernandez, Alberto Rojas-Hernandez, Edith Madai Colunga-Urbina, Iliana Margarita De La Garza-Rodriguez, Miguel Velazquez-Manzanares, Luis Felipe Medina-Vallejo
DOI 10.5155/eurjchem.5.1.1-5.901

In this work, principal component regression and partial least squares regression were used for the estimation of acid dissociation constants through UV-Vis spectrophotometric measurements, considering five well-known acid-base indicators as well as two herbicides as analytes. In each case, an acid-base titration was carried out. Then, the multivariate calibration model was constructed with a few absorption spectra of the series at extreme pH values, to which values of the dissociation fraction (α) of 1 or 0 were assigned, in the case of HA or Aspecies. After that, the prediction step consisted in the estimation of α for the rest of the series. Then, distribution diagrams were built up with α vs pH, to find α = 0.5 where pH = pKa. The results were compared with those obtained through multivariate curve resolution-alternating least squares and program stability quotients from absorbance data (SQUAD), which showed an excellent correspondence.

Masaki Ichitani, Soh-ichi Kitoh, Keiko Tanaka, Shuhei Fujinami, Mitsuhiro Suda, Mitsunori Honda, Ko-Ki Kunimoto
DOI 10.5155/eurjchem.5.1.6-10.933

Crystal structures of racemic and enantiomeric 5-isopropyl-5-methylhydantoin (IPrMH) have been determined by single crystal X-ray diffraction. Melting temperatures and solid state infrared spectra are also measured. Racemic IPrMH has a lower melting temperature than the pure enantiomer by 25 °C. The infrared spectrum of racemic IPrMH is identical with that of the pure enantiomer. Nevertheless, the racemic IPrMH doesn’t crystallize as a conglomerate but as a racemic compound. The racemic and the enantiomeric crystals are very similar to each other in molecular geometries and intermolecular interactions. In the both cases, the molecules are connected via N−H···O hydrogen bonds to form R22(8) rings, and these rings are linked into infinite one-dimensional tapes. In the racemic crystal, a single tape is composed of single enantiomer and itself is homochiral.

Mohamed Rizk, Safaa Shafik Toubar, Maha Mahmoud Abou El-Alamin, Marwa Mohamed Mahmoud Azab
DOI 10.5155/eurjchem.5.1.11-17.885

A micellar liquid chromatographic method was developed for determination of Itraconazole in bulk, dosage form and human plasma using µBondapack cyano column and a mobile phase consisting of 0.1 M sodium dodecyl sulphate, 20% 1-propanol, 0.3% triethylamine in 0.02 M orthophosphoric acid (pH = 3.5). The UV detection was achieved at 258 nm. Various chromatographic parameters were studied, e.g. types of columns, pH of mobile phase, concentration of sodium dodecyl sulphate, 1-propanol, triethylamine, etc .The method was linear over the concentration range 16.4-320.0 µg/mL with regression coefficient 0.999 and limit of detection 5.4 µg/mL in bulk. Inter and intra-day results showed %RSD < 1.49%. The result obtained by the proposed method was compared with that obtained by the reference HPLC technique. Furthermore, the proposed method was successfully applied as stability-indicating method for determination of Itraconazole under different stressed conditions. The method showed good selectivity, repeatability, linearity and sensitivity according to the evaluation of the validation parameters.

Mohammed Rizk, Safaa Shafik Toubar, Hossam Ezz El-Din Sayour, Dalia Mohamed, Rehab Moussa Touny
DOI 10.5155/eurjchem.5.1.18-23.876

A new potentiometric sensor based on molecularly imprinted polymer (MIP) was fabricated for the recognition and determination of imidocarb dipropionate. The MIP was synthesized using imidocarb as the template material, methacrylic acid as a functional monomer, and ethylene glycol dimethacrylate as a cross linking agent. The sensor showed a high selectivity and a sensitive response to the template molecule in aqueous solution. The MIP-electrode exhibited a near-Nernstian response in a wide concentration range 10-5 - 10-2 M with a lower detection limit of 2×10-6 M. The potentiometric conditions were carefully studied and all measuring parameters were optimized including pH, buffer type, plasticizer type, response time and stability. The applicability of the sensor was tested through potentiometric determination of imidocarb dipropionate in pure drug as well as in pharmaceutical formulation. The proposed method was statistically compared with a reported one showing no significant difference regarding accuracy and precision, which assured a good reliable novel sensor for imidocarb estimation.

Magda Ismail Marzouk, Galal Hosni Sayed, Mohamed Said Abd ElHalim, Salma Yehia Mansour
DOI 10.5155/eurjchem.5.1.24-32.870

The reactivity of hydrogen atoms at C-4 of pyrazolone 3 towards condensation reactions was studied by its reaction with p-anisaldehyde, malononitrile and/or ethyl acetoacetate in the presence of ammonium acetate and/or piperidine, glucose, phenyl isothiocyanate, 2-amino thiazole and aniline to afford compounds 4-6, 13, 15, 17 and 18, respectively. Reaction of amino carbonitrile 4 with ammonium thiocyanate, and formamide afforded compound 7 and pyrazolo[3,4-b]pyridinylformamide, 9. Reaction of compound 7 with hydrazine hydrate gave thiocyanato-1,3,4-thiadiazol-2-yl)-1H-pyrazolo[3,4-b]pyridin-6-amine derivative, 8. Acetylation of amino carbonitriles 4 and 5 afforded compound 10 and 11, respectively. Reaction of compound 11 with hydrazine hydrate afforded azanediyl compound 12. The pyrazolone 19 reacted with different nitrogen nucleophiles such as hydrazine hydrate, urea, thiourea and hydroxylamine hydrochloride to afford compounds 22-25. The reactivity of pyrazolone 19 as an α,β-unsaturated compound towards several carbon nucleophiles under Michael reaction was studied by its reaction with ethyl acetoacetate, ethyl cyanoacetate, and malononitrile under different reaction conditions and pyrazolone 3 to afford compounds 26-32, respectively. Synthesis of amino carbonitriles 5, pyrazolone 19 and pyrazolo[3,4-c]pyrazole 22 were carried out under microwave irradiation. The newly synthesized compounds were characterized by IR, 1H NMR and mass spectral data.

Marwa Sayed Salem, Maher Abd El-Aziz Mahmoud El-Hashash, Al-Shimaa Omar Ali Mahmoud, Hassan Mohamed Fawzy Madkour
DOI 10.5155/eurjchem.5.1.33-40.900

The chemical reactivity of 4-(2-tetryl)-4-oxobut-2-enoic acid towards carbon, nitrogen, oxygen, sulfur nucleophiles and binucleophiles namely o-phenylenediamine, o-aminophenol, and o-aminothiophenol has been studied. The investigated nucleophilic reactions result in the formation of heterocyclic compounds with fused and non-fused systems namely, pyridazinone, tetrhydroquinoline, quinoxalone, oxazinone, thiazole and benzocoumarin.

Nadia Ahmed Abdalla, Mohamed Tawfek El-Haty, Farok Abd-Elkarim Adam, Fatma Wafdy Hassan
DOI 10.5155/eurjchem.5.1.41-52.825

The spectral behavior of some new arylazo-2,6-diamino-4-pyrimidinol in pure and mixed organic solvents and buffer solutions of varying pH have been studied. The observed bands are assigned to the possible electronic transition. The band appearing in the visible region is assigned to p→p* transition involving p-electronic system of the whole compounds, associated with intramolecular charge transfer. This charge transfer seems to originate from the aryl moiety to the pyrimidine ring which is characterized by accepting character. This behavior can be explained that these compounds exist in the hydroxyazo-quinoid hydrazon tautomreic explained equilibrium. The possibility of the formation of a-H-bond solvated molecular complex between the molecule of azo 2,6-diaminopyrimidinol and proton-acceptor solvents of DMSO and DMF molecular were discussed. The pK values of these compounds were determined and on the basis of the relative contribution of acidic basic character of respective species.

Doddahosuru Mahadevappa Gurudatt, Kikkeri Narasimha Shetty Mohana
DOI 10.5155/eurjchem.5.1.53-64.899

The influence of four newly synthesized pyrimidine derivatives on the corrosion inhibition of mild steel in 0.5 M HCl solution is studied using mass loss and electrochemical techniques. The corrosion rate was found to depend on concentration and temperature of the medium. Adsorption of all the four inhibitors obeys Langmuir isotherm model. Polarization curves indicated that the studied inhibitors are of mixed type. Electrochemical impedance spectroscopy explains the mechanism of inhibitor’s action. Various activation and adsorption thermodynamic parameters were calculated and discussed. The results obtained from weight loss and electrochemical studies are in good agreement with each other. The variation in inhibitive efficiency mainly depends on the type and nature of the substituents present in the inhibitor molecule.

Hemdan Ibrahem Mahmoud, Said Mnaa Gad ElRab, Ayman Fathey Khalil, Samah Mohamed Ismael
DOI 10.5155/eurjchem.5.1.65-72.903

The aim of the present study was to investigate the hypoglycemic effect of white (Morus alba L.) and black (Morus nigra L.) mulberry fruits either used individually or in a combination on alloxan diabetic rats. These fruits are reported to be rich in antioxidants, flavonoids and phenolics that can potentially fight against diabetes mellitus. Male albino rats were divided into 5 groups: normal control, alloxan-diabetic control, diabetic rats treated with white mulberry fruit powder at 5% in the diet, diabetic rats treated with black mulberry fruit powder at 5% in the diet and diabetic rats treated with mixture of white and black mulberry fruits powder at 5% in the diet. After 4 weeks of treatment, blood glucose level, liver and kidney enzymes activity, lipid profile, lipid peroxidation and histopathological studies on liver, kidney and pancreas were evaluated. The mixture of white and black mulberry fruits showed the most significant (p < 0.05) improvement in feed efficiency ratio with increasing body weight gain, as well as decrease in blood glucose level and liver-kidney dysfunction when compared with diabetic control rats. Significant decrease in serum cholesterol, triglycerides and low density lipoprotein cholesterol (LDLc) as well as significant increase in high density lipoprotein cholesterol (HDLc) in diabetic rats was observed with all treatments. Moreover, mulberry fruits administration caused significant inhibition in lipid peroxidation and α-amylase activity. In addition, the beneficial effect of all treatments was further confirmed with histopathological examination of liver, kidney and pancreas. This study reveals hypoglycemic and hypolipidemic effects of white and black mulberry fruits either used individually or in combination as a dietary supplement in alloxan diabetic rats.

Marwa Hosny Tammam
DOI 10.5155/eurjchem.5.1.73-80.884

The photostability of gemifloxacin mesylate (GFLX) and lomefloxacin hydrochloride (LFLX) antibacterial agents in dilute aqueous solutions (bulk powder and dosage form) was studied by applying the International Conference on Harmonization (ICH) recommended conditions. The photodegradation processes were monitored by UV-Vis spectrophotometry and quantified by HPLC. The structures of degradation products in the aqueous solution have been deduced from LC-MS/MS. The GFLX and LFLX photodegradation kinetic rates were also determined. The photodegradation process for GFLX and LFLX solutions can be described as first order kinetic with rate constants 0.105 and 0.119 1/h, respectively, under the applied experimental conditions. The photodegradation rates of GFLX (0.119 1/h) and LFLX (0.0.157 1/h) in aqueous solutions were higher in dosage forms than bulk powder. Titanium dioxide cannot be used as an opacifier with these fluoroquinolone drugs because the rates of photodegradation of GFLX (0.0.161 1/h) and LFLX (0.0.164 1/h) were significantly enhanced by the addition of TiO2. The obtained results showed that these fluoroquinolone drugs are photolabile, thus these two drugs should be strictly protected from light during storage, administration and drug analysis.

Khairia Mohammed Al-Ahmary
DOI 10.5155/eurjchem.5.1.81-84.881

A simple spectrophotometric method has been described for the determination of thiamine. The method is based on the precipitation of sulphur as barium sulphate using barium chloride after oxidation of thiamine by sodium hydroxide and hydrogen peroxide. Beer's law was obeyed over the concentration range from 2-32 µg/mL thiamine. The average of standard deviation was 1.18×10-2; standard error, 5.20×10-3; relative standard deviation, 0.51%; relative standard error, 5.40×10-3; 95% coefficient, 1.48×10-2; the limit of detection, 0.41 µg/mL; the limit of quantification, 1.38 µg/mL and recovery, 100.03% thiamine. Finally, the developed method was applied to the determination of thiamine in pharmaceutical formulations.

Salman Ahmad Khan, Abdullah Mohamed Asiri, Sanjay Kumar, Kamlesh Sharma
DOI 10.5155/eurjchem.5.1.85-90.789

Various pyrazoline and pyrimidine derivatives were synthesized by the reaction of thiosemicarbazide / phenyl hydrazine / hydrazine hydtate / thiourea / urea with 3-(3,4-dimethoxy-phenyl-1-(2,5-dimethyl-thiophen-3-yl)-propenone under microwave irradiation, which itself was derived from the reaction of 3-acetyl-2,5-dimethylthiophene with 3,4-dimethoxy benzaldehyde. The corresponding pyrazoline and pyrimidine derivatives were obtained in good to excellent yields. All of the new compounds obtained were characterized by IR, 1H NMR, 13C NMR, MS and elemental analyses. The anti-bacterial activity of these compounds were tested in-vitro by the disk diffusion assay against two Gram-positive and two Gram-negative bacteria. The results showed that one of the pyrazoline derivatives is better at inhibiting the growth as compared to chloramphenicol against both types of the bacteria (Gram-positive and Gram-negative). Furthermore, all the molecules were subjected to computational calculation using the density functional theory with B3LYP method to corroborate their antibacterial activities.

Chalya Mallappaji Shivaprasad, Swamy Jagadish, Toreshettahally Ramesh Swaroop, Chakrabhavi Dhananjaya Mohan, Rangaswamy Roopashree, Kothanahally Shivaramu Sharath Kumar, Kanchugarakoppal Subbegowda Rangappa
DOI 10.5155/eurjchem.5.1.91-95.866

A series of benzisoxazole derivatives were synthesized and evaluated for their antibacterial, antioxidant and anti-inflammatory activities. The results indicated that most of the compounds exhibit moderate antimicrobial activity against Gram negative (Escherichia coli, Klebsiella pneumoniae, Salmonella typhi, Shigella flexineri) and Gram positive (Bacillus subtilis) bacterial culture. The molecules were evaluated for antioxidant activities using 2,2-diphenyl-1-picrylhydrazyl scavenging, super oxide radical scavenging and hydroxyl radical scavenging assays and most of them showed good antioxidant activities. Also, the synthesized compounds were screened for anti-inflammatory activities such as lipoxygenase inhibition and indirect haemolytic assays.

Ramzia Ismail El-Bagary, Ehab Farouk Elkady, Marwa Ahmed Hegazi, Nour Eldin Amin
DOI 10.5155/eurjchem.5.1.96-100.865

Accurate, precise and simple spectrophotometric methods have been developed and validated for the determination of paracetamol (PAR) and dantrolene sodium (DAS). Spectrophotometric methods including zero order, first derivative (1D) and derivative ratio methods (1DD) have been developed. The zero order spectrophotometric method was used for the determination of DAS in the range of 1-20 μg/mL by measuring the absorbance at 379 nm where PAR exhibits zero reading. 1D and 1DD methods were used for the determination of PAR in the range of 1.5-20.0 μg/mL by measuring the peaks amplitudes at 265.5 nm and 265.0 nm, respectively. The proposed methods were used to determine PAR in binary mixture with DAS in the laboratory prepared mixtures and in pharmaceutical dosage form. The results obtained were statistically evaluated and found to be accurate and precise and can be satisfactorily applied for the quality control analysis of the cited drugs.

Tasnima Zannat, Mohammed Jamaluddin Ahmed
DOI 10.5155/eurjchem.5.1.101-110.882

An ultra-sensitive and highly selective non-extractive spectrophotometric method is presented for the rapid determination of iron (III) at trace levels using 1,2-dihydroxybenzene-3,5-disulfonic acid (Tiron) as a new spectrophotometric reagent (lmax = 665 nm) in slightly acidic aqueous (2×10-6 - 2×10-5 mol/L H2SO4) solution. The reaction is instantaneous and absorbance remains stable for over 24 h. The average molar absorption coefficient and Sandell’s sensitivity and detection limit were found to be 6.0×105 L/mol.cm, 10 ng/cm2, and 1 µg/L, respectively. Linear calibration graphs were obtained for 0.02-70.00 mg/L of Fe(III). The stoichiometric composition of the chelate is 2:3 (Fe(III):Tiron). Large excesses of over 50 cations, anions and complexing agents (e.g. Tartrate, oxalate, citrate, phosphate, thiourea, and thiocyanate) do not interfere in the determination. The method was successfully used in the determination of iron in several standard reference materials (Alloys and steels) as well as in some environmental waters (portable and polluted), biological samples (Human blood and urine), food, pharmaceutical and soil samples, solution containing iron (II) and iron (III) and some complex synthetic mixtures. The method has high precision and accuracy (s = ±0.01 for 0.5 mg/L).

Ahmed Hamdy Halawa, Ahmed Abd El-Hameed Hassan, Mohamed Ahmed El-Nassag, Mahmoud Mohamed Abd El-All, GehadAbd El-Raheem Abd El-Jaleel, Essam Mohamed Eliwa, Ahmed Hammam Bedair
DOI 10.5155/eurjchem.5.1.111-121.860

We report on the synthesis of new coumarin derivatives coupled with heterocyclic and bifunctionalized moieties at position 7. The proposed structures were confirmed by correct elemental analysis and spectral data (IR, MS, 1H NMR and 13C NMR). Some selected derivatives were also screened for their antioxidant and anticancer activities. The results indicated that 7-{[6-(4-nitrophenyl)-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-3-yl]methoxy}-4-phenyl-H-chromen-2-one has the highest antioxidant and anticancer activity in tested compounds.

Chandrashekhar Arunrao Ladole, Nilesh Govindrao Salunkhe, Ravindra Sakharam Bhaskar, Anand Shankarrao Aswar
DOI 10.5155/eurjchem.5.1.122-126.911
3,4-Dihydropyrimidin-2(1H)-one/thione derivatives were synthesized in moderate to high yields via one-pot three component Biginelli reaction of aldehydes, ethyl acetoacetate and urea/thiourea in the presence of nanocrystalline MgFe2O4 as an efficient catalyst, in microwave irradiation under solvent free condition. This protocol offers several advantages including good yields of products, short reaction time and easy work-up procedure.
Karna Ji Harkala, Laxminarayana Eppakayala, Thirumala Chary Maringanti
DOI 10.5155/eurjchem.5.1.127-132.1002

A simple and efficient synthesis of eight-membered lactone, Cephalosporolide D has been accomplished from inexpensive and commercially available starting materials. This synthesis utilizes α-aminoxylation catalyzed by L-proline reaction, Jacobsen’s hydrolytic kinetic resolution and Yamaguchi macrolactonization as key steps.

Ahmed Mohamed El-Agrody, Al-Anood Mohamed Al-Dies, Ahmed Mahmoud Fouda
DOI 10.5155/eurjchem.5.1.133-137.923

A convenient and efficient method using microwave assisted synthesis of 4H-benzo[h]chromenes (7 and 8), by the reaction of 4-methoxy-1-naphthol (1) with a mixture of aromatic aldehydes (2) and malononitrile (3) or ethyl cyanoacetate (5) and also, by the reaction of 4-methoxy-1-naphthol (1) with α-cyanocinnamonitriles (4) or ethyl α-cyanocinnamates (6) in ethanolic piperidine solution was examined. Structures of the newly synthesized compounds were established on the basis of spectral data, IR, 1H NMR, 13C NMR, 13C NMR-DEPT and MS data.

Subhash Yenupuri, Agastyaraju Venkata Lakshmi Narasimha Satyanarayana Hariharan, Bharat Kumar Bugata, Divakara Laxman Somayajulu Nori
DOI 10.5155/eurjchem.5.1.138-143.924

A series of 2,3-dihydro-2-(susbtituted)-4-(1-methyl-1H-pyrrol-2-yl)-1,5-benzothiazepines (4a-v) have been synthesized evaluated for their in vitro cytotoxicity and antimicrobial activities. Among the tested compounds for cytotoxicity using Brine shrimp lethality assay, compound 4q exhibited significant cytotoxicity at ED50 values 3.45±0.15 µg/mL. This level of activity was found comparable to that of the reference drug podophyllotoxin with ED50 value 3.61±0.17 µg/mL. Antimicrobial activity was assessed using agar well diffusion assay method against selected Gram-positive, Gram-negative and fungal strains. Among the compounds tested, 4q, 4r and 4l were found to be more active with MIC 16-32 µg/mL against all tested microorganisms.

Divakara Laxman Somayajulu Nori, Kasapu Vishnu Veera Venkata Satyanarayan, Vasudeva Rao Avupati, Bharat Kumar Bugata, Subhash Yenupuri
DOI 10.5155/eurjchem.5.1.144-149.925

A series of 5-benzylidene-1,3-thiazolidine-2,4-dione derivatives (5a-u) were synthesized and tested against α-glucosidase. Preparation of the titled compounds was achieved by reaction of (Z)-4-((2,4-dioxo-1,3-thiazolidin-5-ylidene)methyl)benzaldehyde (4) and aromatic/hetero aromatic ketone. Among the compounds tested, (5p) and (5o) were identified as the most active in vitro with minimum inhibitory concentration (MIC) of 6.56±0.81 and 8.92±0.21 µg/mL against α-glucosidase, respectively. Evaluation of the structure activity relationship of substituents within these series has followed the discovery of a variety of compounds.

Ahmed Ahmed Soliman, Sattar Rajab Majeed, Fawzy Ali Attaby
DOI 10.5155/eurjchem.5.1.150-154.926

Rapid, simple, sensitive and validated spectrophotometric method has been described for the determination of palladium (II) using 2-hydrazinopyridine. The complex product was quantitatively measured at 510 nm and the reaction conditions were studied and optimized. The stoichiometry and the stability constant of the purple colored complex has been determined spectrophotometrically in aqueous solution at 25 oC using Job’s continuous variation and the molar ratio methods. The complex has 1:1 (M:L) molar ratio and Beer’s plot was linear in the concentration ranges 1.06-9.00 μg/mL with corresponding molar absorptivity 2.978×103 L/mol.cm. The limits of detection and Sandell’s sensitivity were also evaluated. The accuracy was evaluated as the % recovery (96.61-102.58) and precision was evaluated as RSD% (0.04-0.41) using inter-day and intraday analyses of multiple samples. The effect of various diverse ions on the determination of Pd(II) has been investigated.

Naushad Ahmad, Rizwan Wahab, Suliman Yousef Al Oma
DOI 10.5155/eurjchem.5.1.155-161.929

A polymeric ligand, 2-imidazolidinthione-formaldehyde (poly-IF), bearing nitrogen and sulfur donor group was synthesized by the polycondensation of 2-imidazolidinthione and formaldehyde in alkaline medium. The synthetic ligand was characterized with micro-analytical and spectral studies. The thermal degradation is investigated by means of dynamic thermogravimetry (TG/DTG) in helium and air atmosphere at various heating rate. The non-isothermal degradation of poly-IF compound was occurred in an inert and air atmosphere. Degradation activation energies were calculated using model free multiple heating rate methods i.e. Flynn-Wall-Ozawa (FWO), Friedman and Kissinger. The compound poly-IF was also tested against strain (Escherichia coli) and it inhibits the proliferation of bacterial growth.

Noland William Broekemier, Noah Curtis Broekemier, Randall Thomas Short, Hector Palencia
DOI 10.5155/eurjchem.5.1.162-166.940

An unsymmetrical, well-defined N-heterocyclic carbene-palladium-η3-allyl chloride complex has been synthesized and used as an efficient catalyst for the Suzuki-Miyaura cross-coupling of aryl bromides and activated aryl chlorides. The catalyst provides moderate to high yields of cross-coupling products at 50 °C in 2 hours, using 1 mol % of the catalyst and isopropyl alcohol as solvent.

Vijay Manneganti, Badari Narayana Prasad Rachapudi, Lakshmi Anu Prabhavathi Devi Bethala
DOI 10.5155/eurjchem.5.1.167-170.917

A series of β-hydroxyazides were effectively synthesized from the regioselective ring opening of oxiranes by azide anion in presence of glycerol-based sulfonic acid functionalized carbon as a novel reusable heterogeneous catalyst in H2O achieving good yields (80-98%). The workup procedure was simple, and the catalyst could be reused over five times without losing its catalytic activity and selectivity.

Harvinder Singh Sohal, Arun Goyal, Rajeev Sharma, Rajshree Khare
DOI 10.5155/eurjchem.5.1.171-175.943

Multi component, one pot synthesis of symmetrical 1,4-dihydropyridine derivatives from the condensation of ethyl/methyl acetoacetate, aromatic/aliphatic aldehyde and ammonium acetate has been described using glycerol, as economical, easily available and environmentally benign reagent. The targeted molecules were obtained in high purity and excellent yield without use of any additional catalyst and methodology from readily available starting materials.

Ventzislav Rusanov, Anife Ahmedova, Mariana Mitewa
DOI 10.5155/eurjchem.5.1.176-180.972

An air stable Fe(II) complex of a cyclic β-triketone, 2-acetyl-1,3-indandione (2AID) was obtained in two different ways and studied by Mössbauer spectroscopy. The Mössbauer data at room temperature point to six-coordinated, high spin Fe(II) complex. The temperature-dependent measurements indicate a phase transition in going from 293 to 77 K. Further lowering the temperature, however, do not cause the expected changes for spin-crossover transition. This data provoked application of quantum chemical methods to determine the origin of the observed appearance of spectral component attributable to low spin Fe(II) complex at 77 K. Based on the results from the theoretical calculations of the Mössbauer parameters of several different geometries and spin states of the Fe complexes of 2AID it was possible to conclude that the obtained Fe(II) complex has a pseudo-octahedral geometry. The experimentally observed temperature-dependence of the Mössbauer spectra is attributed to changes of the axial Fe-O bonds, rather than to spin transition. Discussion is given on the role of the type of the axial ligands for conditioning a spin-crossover process, as suggestion for experimental modelling of novel target materials with desired magnetic properties.

Dalia Mohamed, Shereen Mowaka, Ahmed Mostafa
DOI 10.5155/eurjchem.5.1.181-185.942

A sensitive, rapid, selective and accurate liquid chromatography coupled to quadrupole tandem mass spectrometry (LC-MS/MS) method was developed for simultaneous identification and quantification of tamsulosin and finasteride in bulk and in their combined dosage form. Chromatography was performed on a Hypersil gold 50 mm × 2 mm (1.9 μm) column, using acetonitrile:ammonium acetate (90:10, v:v) pH = 3.5 as the mobile phase. Protonated ions formed by a turbo ion-spray in positive mode were used to detect the analytes as well as the internal standard (IS). MS/MS detection was carried out by monitoring the fragmentation of 408.74 → 227.29 (m/z), 373.11 → 304.96 (m/z) and 255.75 → 166.15 (m/z) for tamsulosin, finasteride and diphenhydramine (IS), respectively, on a triple quadrupole mass spectrometer. The linearity was obtained over the concentration range of 1.6-40.0 ng/mL for tamsulosin and 20.0-500.0 ng/mL for finasteride with a lower limit of detection of 0.5 ng/mL and 5.0 ng/mL for the two drugs, respectively. The proposed method was successfully applied to tamsulosin and finasteride determination in pharmaceutical dosage form. The results obtained were statistically analyzed and compared with those of reference ones; in addition, the method was validated according to USP 34 recommendations. The simplicity and sensitivity of this method allows its use in the quality control of the cited drugs and can be extended for routine analysis of the drugs in their pharmaceutical preparations.

Ammal Esmaeel Ibrahim, Hiba Ali Hasan, Alaa Hussein Jawad
DOI 10.5155/eurjchem.5.1.186-188.938

Myocardial infarction (MI) is considered as the major cause of death and disability worldwide, and despite considerable advances in diagnosis and treatment, continues to be a major public health problem. Interleukin-17 (IL-17) is leukocyte-derived cytokine with effects especially on epithelial cells in various tissues. This study designed to investigate the level of IL-17 and its effect on lipid profile in patients with Acute Myocardial Infarction. The study included 50 patients with acute myocardial infarction forty healthy subjects as control group. The levels of IL-17 were significantly elevated in all patients groups (p < 0.001), total cholesterol, LDL, VLDL were significantly elevated (p < 0.001) in all patients as well.  There was positive correlation between IL-17 with HDL, while there was negative correlation with total cholesterol and LDL. The results show significant increase in levels of IL-17, in acute myocardial infarction patients. IL-17 positively correlated with HDL and negatively correlated with total cholesterol and LDL, which lead to consider it as cardio protective factor.


Short Communication

Ayaz Anwar, Abdul Hameed, Shahida Perveen, Maliha Uroos, Muhammad Iqbal Choudhary, Fatima Zahra Basha
DOI 10.5155/eurjchem.5.1.189-191.916

Thirteen dihydropyridine analogues 1-13 were synthesized and evaluated for their DPPH radical scavenging activity. A good to moderate antioxidant activity ranging from 127.4 to 284.5 μM was observed and structure-activity relationship was established. The 3'-fluoro derivative 8 (IC50 = 127.4±3.5 μM) was found to exhibit highest activity among the dihydro pyridine derivatives 1-13, while the other derivatives 11 (IC50 = 132.5±3.32 μM), 6 (IC50 = 142.2±0.60 μM), 10 (IC50 = 144.7±2.46 μM), 12 (IC50 = 153.7±0.50 μM), 5 (IC50 = 161.4±2.81 μM) and 5 (IC50 = 164.4±2.50 μM) possess moderate activity, depends upon the C-4 and C-6 substituted groups. The compounds 7, 13, 4, 3 and 2 have lowest IC50 values, ranging between 172.8 and 284.5 μM. Dihydropyridine analogues were characterized by spectroscopic techniques.


Review Article

Saleh Mohammed Al-Mousawi, Morsy Ahmed El-Apasery, Mohamed Hilmy Elnagdi
DOI 10.5155/eurjchem.5.1.192-200.883

In this review, we report a survey on the synthesis and application of arylazoazines and arylazoazoles as versatile disperse dyes. Recent reports on the synthesis of arylazonicotinates via condensing arylhydrazonals with active methylene nitriles in acetic acid in presence of ammonium acetate is surveyed. The scope and limitations of this synthetic approach which in some cases afford pyridazinones or arylazonicotinates is defined. Microwave assisted as well as ultra sound assisted synthesis of arylazopyridones as established marketed dyes is also surveyed. Conversion of these arylazopyridones into arylazothienopyridones that can de converted into arylazoisoquinoline derivatives is discussed. Synthesis of arylazopyrazoles and pyrazolopyrimidines via microwave or ultra sound is discussed. The utility of the synthesized compounds as well as antimicrobial disperse dyes and efforts to define their potentialities are also covered.


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