000217   Rajavel R;Senthil Vadivu M;Anitha C (Chemistry Dep, Periyar University, Salem-636 011, Email: drrajavel@rediffmail.com) : Synthesis, physical characterization and biological activity of some schiff base complexes. E J Chem 2008, 5(3), 620-6.

Structural modification of organic molecule has considerable biological relevance. Further, coordination of a biomolecules to the metal ions significantly alters the effectiveness of the biomolecules. In view of the antimicrobial activity ligand [bis-(2-aminobenzaldehyde)] malonoyl dihydrazone], metal complexes with Cu(II), Ni(II), Zn(II) and oxovanadium(IV) have been synthesized and found to be potential antimicrobial agents. An attempt is also made to correlate the biological activities with geometry of the complexes. The complexes have been characterized by elemental analysis, molar conductance, spectra and cyclicvoltammetric measurements. The structural assessment of the complexes has been carried out based on electronic, infrared and molar conductivity values.

3 tables, 29 ref, 3 sch

000216   Radha Krishna S;Venkata Naga M;Rao B; Satyanaryana Raju T;Himabindu V;Mahesh Reddy G (Research and Development, Dr Reddy's Laboratories Ltd., Integrated Pro, , Unit-III, Plot No. 116, S V Co-Op. Ind. Estate, Bolaram, Jinnaram, Med, Email: reddyghanta@yahoo.com ) : Isolation, synthesis and characterization of rosiglitazone maleate impurities. E J Chem 2008, 5(3), 562-6.

Three unknown impurities in rosiglitazone maleate 1 bulk drug at level below 0.1 % (ranging from 0.05 to 0.1%) were detected by simple reverse phase high performance liquid chromatography. These impurities were preliminarily identified with LC-MS and characterized by the mass number of the impurities. Different experiments were conducted and finally synthesized and characterized the unknown impurities.

5 ref, 3 sch

000215   Purohit M C;Matthani U C;Joshi R K (Chemistry Dep, H.N.B. Garhwal Univ Campus, Pouri (Garhwal)) : Qualitative and quantitative variation in anthraquinone derivatives and quarcetine glycoside of rheum species from Garhwal Himalaya. Oriental J Chem 2007, 23(2), 629-34.

Rhizomes of two Rheum species were analysed for the presence of anthraquinones and a quercetin glycoside (rutin) by High Performance Liquid Chromatography. Variations in the active contents were found in rhizomes collected from different populations and different altitude. The contents also vary with season and age of the plants.

2 illus, 4 tables, 8 ref

000214   Prasad Y R;Lakshmana Rao A;Rambabu R (NO, University College of Pharmaceutical Sciences, Andhra University, Visakhapatnam-530 003, Email: dryrp@rediffmail.com) : Synthesis and antimicrobial activity of some chalcone derivatives. E J Chem 2008, 5(3), 461-6.

In an effort to develop antimicrobial agents, a series of chalcones were prepared by Claisen-Schmidt condensation of appropriate acetophenones with appropriate aromatic aldehydes in the presence of aqueous solution of potassium hydroxide and ethanol at room temperature. The synthesized compounds were characterized by means of their IR, ¹H-NMR spectral data and elemental analysis. All the compounds were tested for their antibacterial and antifungal activities by the cup plate method.

2 tables, 19 ref, 1 sch

000213   Pramila T;Doshi N;Bheemachari;Udupi R H (Pharmaceutical Chemistry Dep, N.E.T. Pharmacy College, Raichur-584 103) : Synthesis and biological evalution of certain 4 - substituted aryl methylene - 1,3,5 - trisubstituted pyrazoline derivatives. Oriental J Chem 2007, 23(2), 583-6.

Certain 4-subslituted arylmethylene 1,3,5-trisubstituted pyrazoline derivatives have been prepared in good yields. Characterisation of new compounds has been done by means of spectral data and elemental analysis. The biological activities of compounds have been evaluated.

1 sch, 1 table, 9 ref

000212   Prakash D;Birendra Kumar;Suman R P;Prakash S; Yadav H P (Chemistry Dep, Patna Univ, Patna-800 005) : Mixed ligand complexes of Tin(II) and lead(II) metal chelates of some organic acids with acetylsalicylic acid. Oriental J Chem 2007, 23(2), 609-12.

Some new mixed ligand complexes of tin(II) and lead(II) metals with acetyl- salicylic acid having the general formula ML₂.HL where M = Sn(II) or Pb(II); L = deprotonated ONP, DNR TNP have been synthesized by refluxing appropriate reagents in absolute ethanol. The newly synthesized complexes characterized on the basis of elemental analysis, infrared, electronic absorption spectral data and conductivity measurements. The IR spectral data suggest the coordination sites through the oxygen atoms of -OH(phenolic) and -COOH(carboxyl) groups.

3 tables, 5 ref

000211   Prabhu D V (Chemistry Dep, Wilson College, Mumbai-400 007) : Catalytic effect of transition metal ions on the oxidation of some aliphatic alcohols. Oriental J Chem 2007, 23(2), 735-8.

The kinetics of oxidation of the aliphatic alcohols 1- propanol and 1- butanol using Chloramine B (in HCI) has been studied in the micellar phase using sodium dodecyl sulphate in the temperature range 30-50°C. Literature survey shows that expensive Ru (VIII) and Os (VIII) have been routinely used to oxidise alcohols. Less expensive Ni (II), Cu (II) and Zn (II) ions have been used as effective catalysts for the oxidation of aliphatic alcohols. Suitable reaction mechanisms have been proposed for the oxidation of alcohols in the presence and absence of transition metal ion catalysts. The oxidation rate has been correlated with the chain length of the aliphatic alcohols under study.

3 tables, 8 ref

000210   Poongothai N;Natesan M;Palanisamy N;Murugavel S C;Ramachandran T (Chemistry Dep, PSG College of Technology, Coimbatore-641 004, Email: np_gothai@yahoo.co.uk) : Azole, amine, benzoate and nitrate compound mixture as VPI for metals in NaCl and SO₂ environments. Indian J chem Technol 2007, 14(5), 481-7.

A variety of tests were performed to evaluate the feasibility of vapour phase corrosion inhibitor's (VPI's) application for maintenance and protection of transporting metal articles from corrosion damage. Three types of VPI were evaluated for their inhibition characteristics for mild steel (MS) and copper. Minimum dosage of one g/L is required for protections of both metals. Influence of SO₂ and chloride contamination on inhibitor performance was also investigated. The corrosion behaviour of MS and Cu in sodium chloride (0.005 M NaCl) environment in presence of VPI impregnated and unimpregnated paper has been studied by using weight loss, potentiodynamic polarization and A.C impedance spectroscopic methods. It has been found that 1g L^-1 of VPI impregnated on Kraft paper provides nearly 98% inhibition efficiency for mild sled and copper in 0.005 M NaCl environment.

5 illus, 4 tables, 21 ref

000209   Patil T J (Chemistry Dep, Z.B. Patil College, Deopur, Dhule) : Surface and thermodynamic behaviour of polyelectrolyte with a non-ionic surfactant in aqueous medium at different temperatures. Oriental J Chem 2007, 23(2), 653-7.

Surface and thermodynamic studies of aqueous polymer-surfactant system provide valuable information regarding the mechanism of interaction between unlike molecule. Critical micelle concentration (cmc) of pure surfactant decreased with increase in temperature. The cmc of P-S system increased with increase in polymer concentration and temperature. Surface excess concentration (r_max) for pure Triton X-100 in aqueous medium decreased with increase in temperature. Same trend in the (r_max) was observed for the present P-S system with increase in polymer concentration. Minimum area per molecule at the liquid-air interface (A_min>) values for the present P-S system increased with increased in polymer concentration and temperature. Thermodynamic parameters of micellization viz. ΔG°m ΔH°m and ΔS°m have been evaluated at 303,308,313 and 318 K using Phase Separation Model.

1 illus, 2 tables, 25 ref

000208   Patil D B;Chachere S D (Chemistry Dep, Institute of Science, Nagpur-440 001) : Electrochemical oxidation of β-alanine by N-bromosuccinimide. Oriental J Chem 2007, 23(2), 673-7.

The Kinetics of oxidation of β-alanine by N-Bromosuccinimide (NBS) has been studied electrochemically. The specific reaction rate is 8.50 M^-1 s^-1 at 25.0 °C. The energy of activation, frequency factor and entropy of activation are found to be 17.56kJ mole^-1,1.07x 10⁴s^-1 and-176.53 J mole^-1 K ' respectively. The specific reaction rate is influenced by hydrogen ion concentration and dielectric constant of the medium. The most probable mechanism has been suggested.

3 tables, 24 ref

000207   Parameshwara P;Karthikeyan J;Nityananda Shetty A;Shetty P (Chemistry Dep, National Institute of Technology, Karnataka, Surnataka, Surathkal, Srinivasnagar-575 025, Email: nityashreya@rediffmail.com) : Indirect complexometric determination of thallium(III) in its alloys and complexes using thiomalic acid as a selective releasing agent. Indian J chem Technol 2007, 14(3), 308-12.

A simple and selective complexometric method for the determination ot thallium in presence of other metal ions is proposed on the basis of selective masking ability of thiomalic acid towards thallium(III). Thallium present in a given sample solution is first complexed with a known excess of EDTA and the surplus EDTA is titrated with standard lead nitrate solution at pH 5-6, using xylenol orange as the indicator. A 0.6% aqueous solution of thiomalic acid is then added to displace EDTA from the T1(1I1)-EDTA complex. The released EDTA is titrated with standard lead nitrate solution. Reproducible and accurate results are obtained for 3-92 mg of Tl(III) with relative error less than ± 0.17% and coefficient of variation not more than 0.36%. The interference of various ions is studied. This method is used for the analysis of thallium in its synthetic alloy mixtures and also in complexes.

4 tables, 29 ref

000206   Pandey J D;Dey R;Soni N K;Prakash chandra; Yadav M K (Chemistry Dep, Allahabad Univ, allahabad-211 002, Email: jdpandey@rediffmail.com) : Estimation of thermal conductivity of binary liquid mixtures employing new approach. Indian J chem Technol 2007, 14(6), 638-41.

Thermal conductivity of four binary liquid mixtures of polycthers with n-dodecane have been computed using a new approach. Decent agreement has been found between the experimental and estimated values of thermal conductivity for all systems.

2 tables, 6 ref

000205   Pandey A K;Singh S (Electrochemical Laboratory, Kashi Naresh Government PG College, Gyanpur, Sant Ravi Das Nagar, Bhadohi-221 304) : Chelating tendency of sulphur-containing amino acids by solution electrophoresis. Oriental J Chem 2007, 23(2), 647-52.

An innovative solution electrophoresis technique has been used for this study of methyl cysteine complexes of some metals ions viz. Th (IV), Fe (III), Cr (III) and Al (III). 1 : 1 complex is formed by Th (IV) while 1:1 and 1:2 complex is form by Fe(III), Cr (III) and Al (III). The stability constant of the complexes formed were found to be : log k₁ = 8.25 (for Th (IV)), log k₁ = 7.84, log k₂ = 6.83 (for Fe (III)), log k₁ = 7.64, log k₂ = 4.72 (for Cr (III)), log k₁ = 7.33, log k₂ = 5.15 (for Al (III)) at 35°C and ionic strength 0.1 M.

1 illus, 1 table, 19 ref

000204   Nezhadali A;Akbarpour M;Zarrabi Shirvan B (Chemistry Dep, Payam-Noor University of Mashhad, Mashhad-Iran, Email: aziz_nezhadali@yahoo.com) : Chemical composition of the essential oil from the aerial parts of Artemisia herba. E J Chem 2008, 5(3), 557-61.

The aerial parts of the plant artemisia herba were collected in the May 2007 from Babaaman (North Khorassan Province of Iran). The plant was isolated by hydro distillation. A total of 61 constituents, representing more than 98% of the oil were identified by gas chromatograph/mass spectrometry (GC/MS). The main compounds, were alpha-pinene (3.28%), champhene (4.8%), sabinen (5.18%), beta-myrcene (3.04), cis,beta-terpineol (11.31 %), camphor (6.11%), 8-hydroxylinalool (2.64%), L-4-terpineol ( 2.5%), alpha- therpineol (2.33%), myrtenol (3.27%), bornyl acetate (6.2%), alpha-terpinol acetate (3.06%), germacrene (2.06%), davanone (8.49%), trans-fame sol (4.27%), cis-fernesol (2.07%) and 1,3,dicyclopentyl cyclopentane (2.29%). This herbal medicine traditionally uses as anti-infectious, anti-bacterial, emmenagogue, parasiticide, digestive and stomachic and gastric tonic in Iran.

2 illus, 2 tables, 21 ref

000203   Nagalakshmi G (Pharmaceutical Chemistry Dep, The Erode College of Pharmacy, Erode, Email: gn178@yahoo.com) : Synthesis and pharmacological evaluation of 2-(4-Halosubstituted phenyl)-4,5-diphenyl-1H-imidazoles. E J Chem 2008, 5(3), 447-52.

In the study, 2-(4-halosubstituted phenyl)-4,5-diphenyl-lH-imidazoles have been synthesized by refluxing benzil and ammonium acetate with different 4-halosubstituted aromatic aldehydes in glacial acetic acid. The structural assignment of this compound has been made on the basis of elemental analysis, UV, IR, ¹H NMR and Mass spectral data. Toxicity of the compound has been determined. The synthesized compound was evaluated for anti-inflammatory activity against carrageenan induced paw oedema and anticonvulsant activity against maximal electro-shock-induced convulsions in rats.

2 illus, 3 tables, 21 ref

000202   Muralidhar Reddy P;Rohini R;Shanker K; Ravinder V (Chemistry Dep, Kakatiya Univ, Warangal-506 009) : Noval Cu(II) metal complexes with amide ligands: synthesis and spectral chracterization. Oriental J Chem 2007, 23(2), 617-22.

New copper complexes of amide ligands, obtained by condensation of maleic anhydride, succinic anhydride and phthalic anhydride with acetyl hydrazine, 2-amino benzonitrile or 2-amino benzimidazole, were synthesized and characterized. Analytical data and electrical conductivity measurements indicate the formation of 1:1 and 1:2 complexes. Magnetic moments and spectral properties support distorted octahedral and square planar structures for the complexes.

1 illus, 2 tables, 27 ref

000201   Mulazimoglu I E;Ozkan E (Chemistry Dep, Selcuk University, 42099, Konya, Turkey, Email: mulazimoglu@gmail.com) : Investigation of electrochemical behaviour of quercetin on the modified electrode surfaces with procaine and aminophenyl in non-aquous medium. E J Chem 2008, 5(3), 539-50.

In study, cyclic voltammetry and electrochemical Impedance spectroscopy have been used to investigate the electrochemical behaviour of quercetin (3,3',4',5,7-pentahydroxyflavone) on the procaine and aminophenyl modified electrode. The modification of procaine and aminophenyl binded electrode surface with quercetin was performed in +0,3/+2,8 V (for procaine) and +0,4/+1,5 V (for aminophenyl) potential range using 100 mV S^-1 scanning rate having 10 cycle. A solution of 0.1 M tetrabutylammonium tetrafluoroborate in acetonitrile was used as a non-aquous solvent. For the modification process a solution of 1 mM quercetin in 0.1 M tetrabutylammonium tetrafluoroborate was used. In order to obtain these two surface, a solution of 1 mM procaine and 1 mM nitrophenyl diazonium salt in 0.1 M tetrabutylammonium tetrafluoroborate was used. By using these solutions bare glassy carbon electrode surface was modified. Nitrophenyl was reduced to amine group in 0.1 M HCl medium on the nitrophenyl modified glassy carbon electrode surface. Procaine modified glassy carbon electrode surface was quite electroactive. Although nitrophenyl modified glassy carbon electrode surface was electroinactive, it was activated by reducing nitro group into amine group. For the characterization of the modified surface 1 mM ferrocene in 0.1 M tetrabutylammonium tetrafluoroborate for cyclic voltammetryand 1 mM ferricyanide/ferrocyanide (1:1) mixture in 0,1 M KCl for electrochemical impedance spectroscopy were used.

9 illus, 36 ref, 5 sch

000200   Mohan C;Naga Raju C;Janardhan Rao A (Chemistry Dep, Sri Venkateswara University, Tirupati-517 502, Email: naga_raju04@yahoo.co.in) : Synthesis and bioactivity of some new 3-alkyl-2,4-diisopropyl-1,2,4,5-tetrahydro-benzo[e][1,3,2]-diazaphosph epine 3-sulfides/selenides. E J Chem 2008, 5(3), 479-86.

Creparation of a series of novel seven membered heterocyclic compounds, 3-alkyl-2,4-diisopropyl-1 ,2,4,5-tetrahydro-benzo[ e] [1 ,3,2] diazaphosªphepine 3-sulfides / selenides (8a-l) was accomplished in four steps. The synthetic route involves α,α' -dibromo-o-xylene (1) with two moles of isopropylamine (2) in the presence of triethylamine (TEA) in dry tetrahydrofuran (THF) at low temperature to form the compound 3. This on treatment with phosphorus tribromide (4) in the presence of TEA in dry THF to form the corresponding phosphorobromodite (5). This on subsequent reaction with different Grignard reagents (6) in dry THF under N₂ atmosphere formed the compounds 7. They are converted to the corresponding sulfides and selenides (8a-l) by reacting them with sulfur and selenium respectively. Their structures were established by elemental analysis, IR, ¹H, ¹³C, ³¹p NMR and mass spectral data. All the title compounds were screened for their antibacterial activity. Most of the compounds exhibited significant antimicrobial activity.

1 table, 26 ref, 1 sch

000199   Mkpenie V;Ebong G;Obot I B;Abasiekong B (Chemistry Dep, University of Uyo, P.M.B. 1017, Uyo, Nigeria, , Email: proffoime@yahoo.com) : Evaluation of the effect of azo group on the biological activity of 1-(4-methylphenylazo)-2-naphthol. E J Chem 2008, 5(3), 431-4.

Azo-2-naphthol and 2-naphthol were tested against five microorganisms: Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa and Streptococcus faecalis. 2-Naphthol was slightly active while azo-2-naphthol was highly active against all the bacteria species tested. The presence of azo group contributed more than 60% of the antibacterial activities exhibited by azo-2-naphthol on all the bacteria tested.

1 table, 17 ref, 1 scheme

000198   Misra A;Singh S (NO, Chemical Laboratory Kashi Naresh Govt. Post Garduate College, Gyanpur Sant Ravi Das Nagar, Bhadohi-221 304) : Electrochromatographic study of metal-ligand interaction in solution [Be(II)/Pb(II)/Cd(II) and Mn(II)-threonine system]. Oriental J Chem 2007, 23(2), 763-6.

Eleciromigration study of metal ions in a thermostated electrophoretic tube kept under constant electrical potential is described for pin pointing the formation of metal complexes in solution. Reports some of our observations on binary complexing system viz. Be (II), Pb (II), Cd (II) and Mn (II) -Threonine complexes.

1 illus, 1 table, 14 ref

000197   Mishra A;Bhatt V (Chemical Sciences Dep, NVPAS, V.V. Nagar, Anand, Gujarat) : Physico-chemical and microbiological analysis of underground water in V.V Nagar and near by places of Anand district, Gujarat, India. E J Chem 2008, 5(3), 487-92.

A report of physico-chemical and microbial study of the water samples taken from the region nearby Anand district of central Gujarat is presented here. Six water samples are subjected to physico- chemical analysis like pH, TDS, hardness, conductivity, dissolved oxygen and chemical oxygen demand. The MPN count resulted from the bacteriological study of these samples has given the information regarding the suitability of the water for drinking and other domestic applications. The results are analyzed comparatively and conclusions regarding the suitability of the use of such waters are made.

8 illus, 1 table, 11 ref

000196   Manoj Kumar;Jai Pal (Chemistry Dep, Institute of Science and Technology, Kalawad Jagadhri, Yamunanagar, Haryana) : Synthesis, biological, spectral and thermal investigations of macrocyclic complexes. Oriental J Chem 2007, 23(2), 705-12.

The complexation of new macrocyclic ligand viz., cyclo-di-thiocarbahydrazone-bis(2-hydroxy-w-(substitutedben2oyl)-aceto phenonecontaining substituted benzoylacetophenone unit with Cu(II) and Fe(III) has been investigated, by different spectroscopic techniques. These complexes have been characterized on the basis of elemental analyses, spectral(infrared, ESR and electronic) and thermal measurements. Molar conductance and magnetic moment measurements have also been determined. Microanalytical data revealed 1:2 molar ratio of ligand to metal in all the complexes. The elemental analyses are consistent with the formation of the complexes [M(L)(H₂O)₂]Cl₂[where M = Cu(II) and Fe(III); L = ligand (L_l-L_v)]. On the basis of electronic, EPR spectral and magnetic susceptibilities studies an octahedral geometry has been assigned for Cu(II) and Fe(III) complexes. The metal complexes were evaluated for their anti-fungal and anti-bacterial activities on the different species of pathogenic fungi and bacteria and their biopotency has been discussed. The compounds show significant inhibitory activity against bacteria and fungi.

2 illus, 3 tables, 22 ref

000195   Manne S R;Bairy K R;Chepyala K R;Muppa K K; Srinivas R T;Sajja E;Maramreddy S R (Department of Research and Development, MSN Laboratories Limited, Survey No. 317 & 323, Rudraram, Patancheru, Medak District-502 329) : Improved industrial process for synthesis of HMG-CoA reductase inhibitor Pitavastatin. Oriental J Chem 2007, 23(2), 559-64.

An highly efficient cost effective, eco-friendly, commercially viable, convergent synthesis for the manufacturing of Pitavastatin, a HMG-CoA reductase inhibitor, has been developed.

3 sch, 7 ref

000194   Mamatha K;Mogili R;Ravinder M;Srihari S (Chemistry Dep, Kakatiya Univ, Warangal-506 009) : Synthesis and antimicrobial activity of some quinazoline derivatives and their metal complexes. Oriental J Chem 2007, 23(2), 605-8.

A new series of 2,3-disubstituted quinazoline derivatives and their Fe(III), Cu(II), Zn(II) and Hg(II) complexes have been synthesized and tested against F.oxysporum B. subtilis and E. coli. The analytical, spectral and antimicrobial activity data of the compounds synthesized are presented.

2 tables, 14 ref

000193   Madavgane S A;Gogte B B;Subramanian D (NO, Priyadarshini Institute of Engineering and Technology, Nagpur-440 019, Email: mandavgane@rediffmail.com) : Sulphonated lignin based screen ink formulations. Indian J chem Technol 2007, 14(3), 321-4.

An attempt is made to develop a screen ink composition, based on lignin obtained from black liquor as a partial replacement for conventional alkyd resin. Lignin has been used as a replacement for alkyd resin to an extent of 35%. Unlike the conventional alkyd resin, efforts were made to prepare a novel alkyd resin with short oil length (20%) using chain stopper. The overall consumption of petroleum solvent in ink is around 16% which is much lesser than conventional ink which utilizes around 40% solvent. The physicochemical and film properties of ink have been studied and compared with commercial sample. The cost of the present product is less than the conventional product.

2 illus, 7 tables, 13 ref

000192   Liu Y;Hu Q;Lin B (Chemistry Dep, Sciences College, South China Agriculture Univ, 510642, Guangzhou, China, Email: liuyingju@hotmail.com) : Electrochemical study on effect of colloidal Au on horseradish peroxidase in polypyrrole layer at prussian blue modified electrode. Indian J Chem-Sect A 2007, 46(12), 1917-22.

Cyclic voltammetry and current-time curve have been used to investigate the Au-colloid function on the horseradish peroxidase biosensor response. Firstly Prussian blue is deposited on the electrode, and then the polypyrrole (PPY)/HRP biosensor is constructed by electrochemical oxidization of pyrrole in the solution containing horseradish peroxidase and pyrrole. The colloidal Au is then immobilized on the electrode. Cyclic voltammograms show higher current in the presence of Au-colloid as compared to that in the absence of the colloid. The PB/PPY/HRP and PB/PPY/HRP/Au-colloid biosensors exhibit linear current-time response to hydrogen peroxide over a concentration range of 2xl0^-6 M - l.8xl0^-4 M. Michaelis-Menten constants of the two biosensors are 0.63 and 0.35 mM, respectively. The dependence of current responses on applied voltage has been discussed and the mechanism has been proposed. The results show that colloidal Au enhances the current response and decreases the energy barrier of electron transfer reaction on the electrode. The interference of foreign substances has also discussed.

4 illus, 1 table, 26 ref

000191   Kumari N;Saini R K;Joshi Y C (Chemistry Dep, Rajasthan Univ, Jaipur) : Synthesis of noval derivatives of 1,5-benzothiazepines from 1,3-diketones and their antibacterial activity. Oriental J Chem 2007, 23(2), 731-4.

Synthesis of 2,4-disubstituted-1, 5-benzothiazepine (2a-e) is reported by the condensation of 2-aminothiophenol (1) with 1,3-diketones in pyridine which posses better pharmacological activity. The structure of newly synthesized compounds have been elucidated by elemental analysis, IR, ²¹H NMR and ¹³C NMR spectral studies. Newly synthesized compounds were screened for antibacterial activity.

000190   Kumar D;Amit Kumar;Pandey V;Syamal A (Chemistry Dep, National Institute of Technology, Kurukshetra-136 119) : Zirconium (IV) heterochelates. Oriental J Chem 2007, 23(2), 587-90.

A methanolic solution of Schiff base, LH₂ (obtained by the condensation of 3-formylsalicyclic acid and 4-amino-3-methyl-5-thiohydroxy-1,2,4-triazole) reacts with hexadecaaquaoctahydroxo-tetrazirconium (IV) acetate to form seven coordinate zirconium(IV) complex, [Zr(OH)₂ L 2CH₃OH). The later reacts in THF with ON donor bidentate lignads (AA) [where AA= ethanolamine (ea), o-amimophenol (oap), o-aminobenzyl alcohol (oaba), o-hydroxybenzylamine (ohyba) or with NN donor bidentate ligands (BB) [here BB= ethyledediamine (en), trimethylenediamine (tn), o- phenylenediamnine (ophen), 2,2'-dipyridyl (dipy), 1,10-phenanthroline (phen)] to form seven coordinate zirconium (IV) heterochelates, [Zr(OH)₂L(AA)] or[Zr(OH₂L(BB)] respectively. [Zr(OH)₂L-2CH₂OH],[Zr(OH₂)L(AA)] and [Zr(OH)₂L(BB)] have been characterized by elemental analysis, molecular weight, molar conductance, IR and magnetic susceptibility measurements. IR data are indicative of the dibasic tridentate ONS donor nature of LH₂. [Zr(OH)₂L-2CH₂OH],[Zr(OH₂)L(AA)] and [Zr(OH)₂L(BB)] are monomers, non-electrolytes, diamagnetic and possess a pentagonal bipyramidal structure.

1 table, 19 ref

000189   Kiremire E M R;Likius D S;Chibale K;Su H; Kambafwile H (Chemistry Dep, Namibia Univ, Private Bag 13301, Windhoek (Namibia)) : Crystal structure of a new anti-malarial bis {3-[1-(2-pyridyl) ethylidene] hydrazinecarbodithioato} cadmium (II) complex, Cdl₂. Oriental J Chem 2007, 23(2), 415-22.

The synthesized complexes of the general formula ML₂ ( M = Mn, Fe, Co, Ni, Zn, and Cd ; L = 3-[1-(2-pyridyl)ethylidene]hydrazinecarbodithioate ion) were found to have biological activity against cystease protein enzymes, falcipain-2 and falcipain-3 of the malarial parasite and also very high biological activity against the chloroquine resistant strain W-2.The cadmium complex, CdL₂ was found to be about 170 times stronger as compared to the control drug with respect to W-2 and topped the list of the complexes tested. This prompted us to investigate the molecular structure of the complex by X-ray analysis. The complex has been found to have a crystalline triclinic symmetry of space group P-1. The complex adopts a distorted octahedral geometry with the L- acting as a tridentate ligand (NNS) binding to the metal through the pyridine nitrogen, the imine nitrogen and the thiolate sulphur atom.

3 illus, 6 tables, 18 ref

000188   Kamila M M;Mondal N;Ghosh L K (Pharmaceutical Technology Dep, Jadavpur Univ, Kolkata-700 032, Email: profikghosh@rediffmail.com) : Development and validation of spectrophotometric method for estimation of anti-asthmatic drug doxofylline in bulk and pharmaceutical formulation. Indian J chem Technol 2007, 14(5), 532-5.

A simple, sensitive and accurate UV spectrophotomctric method has been developed for the determination of an anti-asthmatic drug, doxofylline, in raw material and in tablets. The drug showed maximum absorption at 272 nm in water. Beer's law-was obeyed in the concentration range 5-50 μg mL^-1 of drug with an apparent molar absorptivity and Sandell sensitivity of 6.2 x 10^{3 L. mol-1cm-1 and 0.0363 μg cm-2/0.001 A, respectively. The limits of detection and quantification were calculated to be 0.9623 and 2.9161 μg mL-1, respectively. The method was successfully applied to the determination of doxofylline in tablets. Results were validated statistically as per ICH guidelines. It was found that the excipients present in the commercial formulation did not interfere with the method.}

2 illus, 12 ref

000187   Kamaruzzaman B Y;Noor Azhar M S;Norhizam H; Willison K Y S (NO, Institute of Oceanography and Maritime Studies, International Islamic, Bandar Indera Mahkota, 2500 Kuantan, Pahang, (Malaysia)) : Temporal variation of organic carbon during the pre-monsoon and post-monsoon season in pahang coastal water, Malaysia. Oriental J Chem 2007, 23(2), 409-14.

Surface sediments collected from 44 stations during pre-monsoon season and post-monsoon season were analyzed for the organic carbon concentration using the total organic carbon analyzer. The sediment particle sizes were also measured at all stations with the laser diffraction method (PSA). In this study, it is interesting to note that the concentration of organic carbon are relatively high in the pre monsoon season and become much lower after the post monsoon season. In the pre monsoon season, organic carbon has average concentration of 1.58% and during post monsoon season, the average concentrations of organic carbon were significant decreased to 1.23%. The mean grain sizes were also showing the same trend with lower phi (φ) values during pre-monsoon season compared to the post-monsoon season. This finding indicates that the annual seasonal changes that occur in Pahang coastal waters might probably has the important role in regulating the concentrations of organic carbon.

2 illus, 18 ref

000186   Jagapathi Raju V;Seshagiri Rao J V L N (NO, University College of Pharmaceutical Sciences, Andhra University, Visakhapatnam-530 003, Email: jvlnsrao@gmail.com) : High performance thin layer chromatographic method for estimation of Cefprozil in tablet dosage form. E J Chem 2008, 5(3), 427-30.

A simple, fast, specific and precise HPTLC method has been developed for the estimation of cefprozil in pure and in tablet dosage forms. Aluminium plates precoated with silica gel G60F₂₅₄ were used as stationary phase and a mixture of chloroform: methanol: toluene: diethyl amine: water in the ratio 4: 4.4: 3.2: 3: 0.8 v/v as mobile phase. Quantification was carried out by the use of a densitometer in absorbance mode at 286 nm. The R_f value of cefprozil was found to be between 0.37 and 0.40. The results of the analysis have been validated statistically and by recovery studies. Linearity was observed in the concentration range of 400-2000 ng/spot.

2 illus, 5 tables, 7 ref

000185   Indrayan A K;Kurian A;Tyagi P K;Shatru A; Kathi A K (Natural Products Lboratory, Chemistry Dep, Gurukula Kang Univ, Hardwar-249 404, Email: akindray@sancharnet.in) : Comparative chemical study of two varieties of attractive medicinal plant Kaempferia galanga linn.. Nat Prod Radiance 2007, 6(4), 327-33.

Kasthuri and 'Rajani' varieties of medicinal and ornamental plant Kaempferia galanga Linn, differ morphologically. The essential oils from their rhizomes have remarkably different specific gravities, refractive indices, saponification and iodine values. These oils also differ sufficiently in their chemical compositions. A total no. of 58 and 56 compounds have been identified in 'Kasthuri' and 'Rajani', respectively. Thirteen compounds are identified in the rhizome oil of 'Kasthuri' that are not present in the rhizome oil of 'Rajani' and another 11 compounds identified in 'Rajani' oil are not present in 'Kasthuri' oil. Forty-five compounds have been found common in both oils but their percentages differ in the two varieties. Similarly major component, ethyl-trans- p-methoxydnnamate is present in both the varieties, its percentage varies (39and35%, respectively).

3 tables, 31 ref

000184   Ibrahim V (NO, Egyptian Petroleum research Institute, Cairo (Egypt)) : Interfacial tension γ upon the addition of alcohols to some sulfonate systems. Oriental J Chem 2007, 23(2), 399-408.

1-phenyl dodecane sulfonate, 1-phenyltetradecane sulfonate, 1-phenylhexadecane sulfonate, 3-phenyl-tetradecane sulfonate and 5-phenyltetradecane sulfonate were prepared and evaluated on a laboratory scale for enhanced oil recovery (EOR) formation systems. The effect of added alcohols on the interfacial tension of these system, also dynamic interfacial tension (ϒ) of these anionic surfactants against n-alkanes were investigated to obtain the ultralow interfacial tension of these systems, also dynamic interfacial tension was discussed. This work may be helpful for designing practical formulations used for surfactant flooding systems.

1 illus, 6 tables, 25 ref

000183   Hipparagi S.M.;Geethavani M.;Suresh Kumar V; Parikshit B (Pharmaceutical Chemistry Dep, K.L.E.S's College of Pharmacy, 2nd Block, Rajajinagar, Banglore-560 010) : Microwave assisted synthesis of fluoro substituted quinoxaline derivatives for antimicrobial studies. Oriental J Chem 2007, 23(2), 571-6.

N-(3-chloro-4-fluorophenyl) acetamide was prepared from 3-Chloro-4-fluoro aniline.This was followed by synthesis of N- (3-chloro-4-fluoro-2-nitro Phenyl) acetamide by nitration, which was followed by hydrolysis and carried out in microwave oven at 320 watts for 5 minutes to get 3-chloro-4-fluoro-2-nitroaniline, where as the time required for the same step by conventional method was about 1 hour. This was then subjected for reduction to get3-chloro-4-fluorobenzene-1,2-diamine. Cyclization of 3-chloro-4-fluorobenzene-1, 2-diamine with benzil was carried out in solvent free condition in microwave by irradiating at 320 watts for 90 seconds to gel 5-chloro-6-fluoro-2, 3-diphenyl quinoxaline. The time taken for the same step by conventional method was about 1 hour.Various derivatives were prepared by replacing the chlorine atom by different amines from 5-chloro-6-fluoro-2, 3-diphenyl quinoxaline by using modified microwave oven with reflux condenser and thermostat regulator for 1 hour. The time taken for the above step by conventional method was about 14 hours and it was reduced to 1 hour by using modified microwave oven. The synthesized compounds have been characterized by analytical and spectral studies (IR, 'H NMR and Mass) and screened for their antimicrobial activity. The yield of the compounds synthesized by using microwave oven was more when compared to conventional method.

10 sch, 8 ref

000182   Hipparagi S M;Majumder U K;Parikshit B; Geethavani M;Suresh Kumar V (Pharmaceutical Chemistry Dep, K.L.E's College of Pharmacy, 2nd Block, Rajajinagar, Bangalore-560 010) : Microwave asited synthesis and antimicrobial activity of 7-chloro-6-fluoro-2-(substituted aromatic sulphonyl hydrazino) benzothiazoles. Oriental J Chem 2007, 23(2), 665-8.

Prepares 7-chloro-6-fluoro-benzothiazole-2-ylamine(P) from 3-chloro-4-fluoro-phenylamine. 7-ch1oro-6-fluoro-benzothiazole-2-ylamine on treatment with hydrazine hydrate in microwave oven for 6minutes to get 7-chloro-6-fluoro-benzothiazol-2-yl-hydrazine(PB) which on treatment with different substituted aromatic sulphonyl compounds yields the title compounds(PB 1-9). Various compound and their derivatives were prepared and conformed by IR, NMR and Mass spectra. Antimicrobial study shown that synthesized compounds have moderate activity.

1 illus, 1 table, 7 ref

000181   Hipparagi S M;Majumder U K;Nargund L V G (Pharmaceutical Chemistry Dep, K.L.E.S's College of Pharmacy, 2nd Block Rajaji Nagar, Bangalore-560 010) : Synthesis and antimicrobial activity of 8-substituted-7-fluoro-2H-benzo[4,5]Thiazolo [2,3-c][1,2,4] triazol-3-one. Oriental J Chem 2007, 23(2), 739-42.

Synthesizes 7-Substituted-6-fiuorobenzothiazol-2-ylamine from 3-Chloro-4-fluorophenylamine. 7-substituted-6-fluorobenzothiazol-2-ylamine were treated with hydrazine hydrate to get 7-substituted-6-fluoro-benzothiazol-2-yl-hydrazine and then prepared 8-Substituted-7-fluoro-2H-benzo[4,5]thiazolo [2,3-c][1,2,4]triazol-3-one by treating ethyl chloroformate as a cyclising agent. Prepares different derivatives of this compounds its confirmed by IR, NMR.The study of antimicrobial activity reveals that the synthesized compounds have moderate activity.

000180   Hakimi M;Nezhadali A;Naemi A (Chemistry Dep, Payame Noor University (PNU), Fariman-Iran, Email: hakimi@pnu.ac.ir) : Conductometric study of complex formation between Cu(II) ion and 4-amino-3-ethyl-1,2,4-triazol-5-thione in binary ethanol/water mixtures. E J Chem 2008, 5(3), 551-6.

The stability constant, K_f, for the complexation of copper(II) ion with 4-ammo-3-ethyl-1,2,4-triazol-S-thione (AETT ) in 0, 20, 40, 60 and 80 (v/v) % ethanol-water mixtures were determined conductometrically at different tempratures. Stability constant of resulting 1:1 complexes were being larger by increasing of temprature and ethanol percent. Stability constants of complexes vary inversly with dielectric constant of solvents. The enthalpy and entropy of complexation were determined from the temprature dependence of the formation constant. In all cases, the complexation were found to be enthalpy unstablized but entropy stablized. ΔG° of the studied complexes were evaluated at 25°C using thermodynamic relations, the negative values of ΔG° means that the complexation process is spantaneously.

3 illus, 2 tables, 26 ref

000179   Gupta A;Sharma S K;Toor A P (Chemical Engineering and Technology Dep, Panjab Univ, Chandigarh, Email: aptoor@yahoo.com) : Empirical correlation in predicting the viscosity of refined vegetable oils. Indian J chem Technol 2007, 14(6), 642-5.

Accurate knowledge of transport properties of oil is essential for mass and heat flow. Viscosity is one of the important properties of an oil which needs to be determined as it influences the ease of handling, transport and nature of storage. The effect of temperature on viscosity of six refined vegetable oils viz. palm oil, rice bran oil, cottonseed oil, mustard oil. sunflower oil and soybean oil has been studied. An empirical correlation between reduced viscosity and reduced temperature has been derived for the determination of viscosities of refined vegetable oils showing Arrhenius behaviour above 20F128><144>C (293 K). This correlation predicts the viscosity of refined vegetable oils at temperatures more than 40-60°C above 20°C (293 K). Consistency tests for viscosity data using reduced parameters have been reported. The viscosities calculated using proposed empirical correlation agree well with the reported experimental values.

4 illus, 1 table, 22 ref

000178   Goswami N;Prabha S (NO, Gwalior Engineering College, Maharajpura, Airport Road, Gwalior) : Synthesis and kinetic study of hydrolysis of phosphoric mono-o-nitrophenyl amide in proton - rich media. Oriental J Chem 2007, 23(2), 659-64.

Synthetic mono-o-nitrophenyl phosphoric amide (as DCHA Salt) a C-N-P ester, hydrolyses bitnolecularly in acid (0.01-7.OM HCI) at 40 (±0.5)°C with P-N bond cleavage. Two rate maxima (0.01 M & 4.0M HCI) in acid - rate profile are in favour of the formation of similar type of transition states from ths modified - Neutral (or zwitter -ionic) and the Conjugate acid species. Neutral species shows its presence in the low acid range (0.1 to 0.5M HCI ). A rigid and a compact T.S. is decided for the Conjugate acid species, on the basis of ΔS', while its low polarity nature is supported by solvent valiation study. For synthesis, phosphorylation of the parent amine (with CTAB catalyst) with POCI₃ was performed and this was then converted in to the DCHA salt for stability reasons.

1 illus, 2 tables, 14 ref

000177   George M;Balasubramanian N;Nagaraja K S (Chemistry Dep, Loyola Institute of Frontier Energy (LIFE), Loyola College, Chennai-600 034, Email: ksnagi@vsnl.net) : Spectrophotometric determination of hydroxylamine and its derivatives in drug formulation using methyl red. Indian J chem Technol 2007, 14(4), 412-16.

Hydroxylamine has been determined by its oxidation to nitrite with a known excess of bromine. Bromine in acidic medium bleaches the dye methyl red. A known excess of bromine when treated with hydroxylamine is reduced to bromide and the unreacted bromine is determined using methyl red. The method obeys Beer's law in the range 0-5 μg of hydroxylamine in an overall aqueous volume of 25 mL. The relative standard deviation is 2.7% (n=10) at 3 μg of hydroxylamine. The molar absorptivity is calculated to be 9.8xl0⁴ Lmol^-1cm^-1 with the correlation coefficient of 0.995. The developed method bas been applied for the determination of hydroxylamine and its derivatives after hydrolysis in drug formulations. The results obtained by the present method compare well with those obtained by the Verma-Gupta's method and with the standard addition of hydroxylamine and recovery studies.

1 illus, 3 tables, 16 ref

000176   Esther Leena Preethi M;Revathi S; Thiripuranthagan S (Catalysis Laboratory, Chemical Engineering Dep, A.C. College of Technology, Anna University, Chennai-600 025, Email: sivakmar@annauniv.edu) : Green synthesis of benzylated aromatics using iron loaded mesoporous materials. E J Chem 2008, 5(3), 467-72.

Syntheses of benzylated aromatics like diphenylmethane and its derivatives by the condensation of benzene or toluene or a-xylene with benzylchloride or 4-methylbenzylchloride in the presence of a catalytic amount of various iron loaded mesoporous solid acid catalysts such as Fe/ Al-MCM-41 (Si/Al=25), Fe/Al-MCM-41 (Si/Al=50) and Fe/Al-MCM-41 (Si/Al=100) are reported.

3 tables, 22 ref, 1 sch

000175   Dutta S;Das A K (Chemistry Dep, Burdwan Univ, Burdwan-713 104, Email: arabindakdas@rediffmail.com) : Determination of lead in environmental samples after solid phase extraction by 2-aminothiazole group incorporated PS-DVB. J scient ind Res 2007, 66(12), 1025-8.

Proposed method for determination of trace amounts of lead is based on solid phase extraction of metal ion by 2-aminothiazole group incorporated into a matrix of polyslyrene-divinylbenzene (PS-DVB). Effect of pH, equilibration rate, sorption and desorption of metal ions, effect of flow rate and effect of diverse ions were studied. Maximum sorption capacity observed for Pb (II) was 0.29 nimolg^-1 at pH 5.5. Calibration range was linear up to 5 μg ml^-1 (R² =0.997) with a detection I of 25.0 μg l^-1. Pb (II) recovery at 97.5% confidence level was found to be 97.5 ± 2.1%.

3 illus, 2 tables, 16 ref

000174   Dewan A;Kakati D K (Chemistry Dep, Gauhati Univ, Gawahati-781 014, Email: dilip_kakati2003@yahoo.co.in) : Regeneration of carbonyl compounds from their oximes using Ce(IV) based phase-transfer oxidants. Indian J chem Technol 2007, 14(6), 635-7.

Regeneration of ketone and aldehyde from their oximes is an important reaction in synthetic organic chemistry. In the oxidative deoximation processes the use of inorganic reagents is restricted by the insolubility of inorganic reagents in organic solvents. However this problem can be alleviated by the use of oxidants, like tetra-alkyl ammonium salts in the form of phase-transfer reagents. In the present case two phase transfer oxidants cetyldimethyl benzyl ammonium cerium nitrate (CDBACN) and cetyltrimelhyl ammonium cerium nitrate (CTACN) were used for oxidative deoximation of oximes of carbonyl compounds. The regenerated carbonyl compounds were characterized from their melting points and spectroscopic analysis.

1 illus, 1 table, 23 ref

000173   Demir I (Chemistry Dep, Faculty of Science and Arts, Nide Univ, Campus / Nigsse - 511 00(Turkey)) : Synthesis and thermal studies of anovel oxime Schiff base ligand and its metal complexes. Oriental J Chem 2007, 23(2), 393-8.

A novel oxime-schiff base ligand, Ethylimino-bis(isonitroso-p-methoxyacetophennone), was synthesized. The complexes of Nickel (II), Copper (II) and Cobalt (II) with oxime-schiff base ligand were prepared. The ligand and their metal complexes were charecterization by spectroscopic techniques. The thermal behaviour of Ethylimino-bis(isonitroso-p-methoxyacetophennone) and its Ni(II), Cu(II)and Co(II) complexes have been studied by DTA and TG.

5 illus, 3 tables, 10 ref

000172   Deepak Kumar;Sinha R;Sharma S (Chemistry Dep Univ, M.U. Bodh Gaya, Botany Dep, A.M. College, Gaya) : Biological reduction of nitrate nitrogen to improve water quality. Proc Zool Soc India 2007, 6(2), 115-19.

The Nitrate Contamination of ground water resources is becoming an ever increasing problem. Because of the adverse health effects due to the presence of the excess of nitrate in drinking water and the concerns regarding decreasing water quality, interest is increasing in the nitrate removal methods and technologies. The present study describes a noble method of denitrification by pseudomonas stutzeri in situ. The results show that nitrate - nitrogen reduction occurs extra oridinarily to the level much lower than the tolerance limit prescribed by WHO. The water quality remains almost the same except the increase in pH due to increase in alkalinity caused by biological denitrification process. The COD of treated water I is found to be zero which indicates that organics have been consumed by the bacterium during the denitrification process. The value of DO in treated water is found to be diminished due to its consumption by the bacterium.

2 tables, 15 ref

000171   Dass Sarma I;Parwate D V (Chemistry Dep, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur-440 033, Email: dassarmaindrani@rediffmail.com) : Plausible applicability of aqueous Congo red dye system as secondary gamma-ray dosimeter. E J Chem 2008, 5(3), 572-6.

Aqueous congo red dye solutions in the concentration range of 0.01-0.03mM were irradiated for varying γ doses 0.050 kGy to 0.150 kGy. The molar extinction coefficient of the dye solution of congo red was found to be 2.70X 10⁵ at its absorption maxima 499.0 nm. No change in λ_max was observed on irradiation. As the dye solutions are sensitive towards γ-irradiation, decolouration occurs on irradiation. The G-values for the doses in between the range of 0.035 kGy to 0.125 kGy were found to be practically constant for pure aqueous systems. Hence this was used to determine the dose of the gamma source. With the addition of alcohols in the systems, degradation of the dyes due to radiations decreased considerably.

4 illus, 7 ref

000170   Das R;Pitre K S (Chemistry Dep, Dr. H.S. Gour Univ, Sagar-470 003, Email: ratnesh_das@yahoo.co.in) : Bioinorganic studies on Fe(II)-idovudine (azt) complex. Indian J chem Technol 2007, 14(5), 526-8.

The anti-HIV drug 3'-Azido-3'-deoxythymidine (Zidovudine) AZT has been quantitatively and qualitatively analysed by direct current polarographic (DCP), differential pulse polarographic (DPP) and arnperometric techniques. AZT gives a well-defined polarographic reduction wave/peak with E_1/2/Ep = - 1.42/ - 1.44 V versus SCE in 0.2 M KCL at pH = 6.0 ±0.1. Fe (II)-AZT complex has been studied both in solid and aqueous phases. The 1R spectral data on the drug and its Fe (ll)-complex revealed complexation through -N atom of azide group. The data showed a shift in the hand due to azide group in the complex from 2170 to 2150 cm^-1 in case of pure drug zidovudine. Hence, a tentative structure of the complex has been suggested. Antibacterial activity of the complex has been determined using Raper's paper disc method against Escherichia coli. Salmonella lyphi, Vibrio cholerae, and Diplococcus pneumoniae bacteria. Looking at its increased inhibition power against the above test pathogens, it is presumed that the complex may prove to be more potent against HIV, as compared to AZT drug.

1 illus, 3 tables, 15 rev

000169   Cheriyan M;SindhuKumar B;Mohanan K (Chemistry Dep, St. Johan's College, Anchal-691 306) : Synthesis, spectroscopic characterization and thermal stabilites of some mixed ligand complexes of Oxovanadium (IV). Oriental J Chem 2007, 23(2), 613-16.

Mixed ligand complexes of oxovandium (IV) with o-carboxyphenlazoacetlaceton as primary ligand and a monodentate base like ethylamine, diethylamine, triethylamine, pyridine or picoline as secondary ligands have been synthesized and characterized on the basis of elemental analysis, molar conductance, magnetic susceptibility, UV-Visible, IR and NMR spectral studies reveal that the ligand exists in the hydrazone form and confirm the tridentate bonding mode through the ONO donor sequence. Thermal decomposition studies on the vanadyl mixed ligand complexes with amines show that the stabilities are in the order tertiary amine<primary amine<secondary arrtine. This observed order of thermal stability appears as a compromise between the basic strength and strain. Thermal stabilities of the complexes containing heterocyclic bases have been also discussed.

1 illus, 2 tables, 14 ref

000168   Chaudhary R S;Tyagi D K;Atul Kumar (Chemistry Dep, M D Univ, Rohtak-124 001, Email: atul_verma1234@rediffmail.com) : Corrosion inhibition of mild steel in hydrochloride acid by cetyl compounds. J scient ind Res 2007, 66(10), 835-40.

Inhibiting effect of cetyl trimethyl ammonium chloride (CTMAC) and cctyl trimethyl ammonium bromide (CTMAB) on the corrosion of mild steel in I M HCl solution have been studied using three different techniques (weight loss, electrochemical polarization studies and surface study by SEM). Weight loss studies were conducted in 1 M 11C1 at different temperatures (25°, 35°&45°C) using various concentrations (50-250 ppm) of inhibitor for 24 h immersion time. Inhibitor efficiency (IE) increases with increase in inhibitor concentrations (50-250 ppm) at a given temperature and time. IE was found to vary with concentration, temperature and immersion lime. Electrochemical polarization result revealed that CTMAC and CTMAB were mixed type inhibitors.

5 illus, 1 table, 20 ref