020518   Chandorkar J G;Pande V V;Dubey S;Chandewar A V (Pharmaceutical Chemistry Dep, Siddhant College of Pharmacy, At Post Sudumbare, Tal: Maval, Pune-412 109, Email: vishalpandey_1376@rediffmail.com) : Development and validation of high performance liquid chromatography method for analysis of gatifloxacin and its impurity. Asian J Chem 2008, 20(3), 2461-3.

A simple isocratic reverse phase high performance liquid chromatographic method was developed for the intermediates and finished products in reaction stream during process development of gatifloxacin. The method was utilized successfully in analyzing the reaction streams, related substances in final product and for the assay in drug.

^ssc4 tables, 3 ref

020517   Budak Y;Findik E;Burcu Gurdere M;Ceylan M (Chemistry Dep, Gaziosmanpasa Univ, Tokat 60250, Turkey, Email: ybudak@gop.edu.tr) : Ring-opening products of 1-phenyltricyclo[4.1.0.0^2,7]-heptane and 2-phenyltricyco[4.1.0.0^2,7]heptane in SiO₂.. Asian J Chem 2008, 20(3), 1943-9.

Treatment of the mixture of 1 -phenyltricyclo[4.1.0.0^2,7]-heptane (8) and 2-phenyltricyclo[4.1.0.0^2,7]heptane (15) with SiO₂ gave the ring-opening products i.e., 2-phenylbicyclo-[4.1.0]hept-2-ene (19), 1-phenylbicyclo[4.1.0]hept-2-ene (20), (1E,4Z)-2-phenylcyclohepta-l,4-diene (21). (E)-3-phenylcyclohept-3-en-l-ol (22) and l-phenylbicyclo[4.1.0]-heptan-2-ol (23). In addition to these products, phenyl (1-phenylbicyclo[4.1.0]heptan-2-yl)sulfane (18) and (Z)-phenyl(2-phenylcyclohept-3-enyl)sulfane (17) were obtained by the addition of PhSH to the mixture of 8 and 15. The addition of bromine to the mixture of 8 and 15 gave 2-bromo-methylbiphenyl as the main product.

13 ref

020516   Bhati D K (NO, , g/o Dr. Ratnakar Bharti, New Colony, Naya Bazar, Ward No. 15, Madhupur, Distt. Deoghar) : Analysis of K-shell fluorescence of Fe, Mn, Co and Cu compounds. Acta Cienc Indica-Chem 2008, 34(1), 141-4.

Analysis of K-shell fluorescence of Fe, Mn, Co and Cu compounds were investigated. Chemical effects on the K shell fluorescence yields (ω_K) for Fe, Mn, Co and Cu compounds were calculated. The values are compared with theoretical, semiempirical fit and experimental ones for the pure elements. Our analysis shows that the changes of the K-shell fluorescence yield values for Fe, Mn, Co and Cu in the compounds can be interpreted as due to changes in the electron population of the valence bands of Fe, Mn, Co and Cu in the compounds. It is believed that the results of study will be helpful for better understanding the dependence of the K-shell fluorescence yield values of changes in the valence electronic configuration of 3d transition metals and throw light on the valence electronic structure of Fe, Mn, Co and Cu in compounds.

1 table, 7 ref

020515   Bharti D K (NO, , C/o Dr. Ratnakar Bharti, New Colony, Naya Bazar, Ward No. 15, Madhupur, Distt. Deoghar, Jharkhand) : Analysis of comprehensive dipole function for the C-H bond. Acta Cienc Indica-Chem 2008, 34(1), 109-13.

Analysis of comprehensive dipole function for the C-H bond is presented. The infra-red intensities for the first for CH₃ stretching overtone bands are used to calculate the dipole function for C-H bond have been analysed on local mode description for methyl chloride. In the present calculations a bond dipole model is assumed describe the molecular dipole function of C-H bond. The functions are found to drop suddenly at inter-nuclear distances away from the equilibrium distances.

5 tables, 16 ref

020514   Beiraghi A;Babaee S (Faculty of Chemistry, Tarbiat Moallem Univ, Mofatteh Aye., No.49, P.O. Box 15614, Tehran, Iran, Email: beiraghi@saba.tmu.ac.ir) : Cloud point extraction based on binary surfactants for separation, preconcentration and spectrophotometric determination of beryllium with 1,8-dihydroxy anthrone. Asian J Chem 2008, 20(3), 1999-2010.

A new micelle-mediated phase separation of metal ions, using mixed micelles of the cationic surfactant cetyl pyridinium chloride (CPC) and non-ionic surfactant Triton-X-114, applied for preconcentrating trace levels of beryllium as a prior step to its determination by spectrophotometry has been developed. Beryllium was compelexed with 1,8-dihydroxy anthrone in an aqueous surfactant medium and it was concentrated in the surfactant rich phase after separation. The chemical variables affecting the cloud point extraction (e.g., pH, surfactant and reagent concentrations, temperature, incubation and centrifuge times) were evaluated and optimized. Under the optimum experimental conditions, calibration graph was linear in the range of 2-120 ng mL^-1 with detection limit of 0.2 ng mL^-1 and the precision (% RSD) for 5 replicate determinations at 60 ng mL^-1 of Be(II) was 0.16%, In this manner the preconcentration and enrichment factors were 25 and 14.2, respectively. The interference effect of some cations and anions was also studied. Finally, the proposed method was successfully applied to the determination of beryllium in synthetic and real water samples.

5 illus, 4 tables, 40 ref

020513   Bazaz R D;Pirali-Hamedani M;Abdi K;Bayrami Z; Rabiei M;Jafari M (Medicinal Chmistry Dep, Faculty of Pharmacy Tehran Univ of Medical Sciences, Tehran, Iran, Email: bazaz1@yahoo.com) : Determination of lead, cadmium, arsenic, iron, zinc, copper, nickel and magnesium in some cultivated Agaricus bisporus and Plurotus ostreatus mushrooms of Iran. Asian J Chem 2008, 20(3), 1871-4.

Several samples of Agaricus bisporus and Pleurotus ostreatus mushrooms from different cultivation farms were collected from the market and after sample preparation were tested by flame atomic absorption spectroscopy for measuring copper, zinc, iron and magnesium. Graphite furnace atomic absorption spectroscopy was applied for measuring cadmium, lead, nickel and arsenic. The results of study showed that content of all measured elements were in close accordance with the similar studies performed previously in other countries.

1 tables, 11 ref

020512   Bansal D;Singhal A P;Mittal R K (Chemistry Dep, Rajasthan Univ, Jaipur-302 004) : Reactions of organotin chlorides with primary amines. J Ultra Chem 2008, 4(1), 133-6.

Complexes of the type, R₂SnCl₂.2L (where R= -CH₃ and L=n-Butylamine or monoethanolamine), R₂SnCl₂.L (where R= -C₄H₉ or -C₆H₅ and L=n-Butylamine), ROSnCl₃.2L (where R= -CH₃ or -C₂H₅ and L= n-Butylamine or monoethanolamine) and ROSnCl₃.L (where R= t-Butyl and L=n-Butylamine) and ROSnCl₃.2L (where R= t-Butyl and L=monoethanolamine) have been prepared. Infrared spectral studies have been carried out to suggest possible structures of the complexes.

1 table, 15 ref

020511   Bansal D;Singhal A P;Mittal R K (Chemistry Dep, Rajasthan Univ, Jaipur-302 004) : Reactions of organotin chlorides with secondary amines. J Ultra Chem 2008, 4(1), 119-22.

Complexes of the type.R₃SnCl.L (where R= -C₆H₅ and L= Et₂NH, Pr₂NH and Bz₂NH) were obtained. Complexes of the type, R₂SnCl₂.2L (where R=-CH₃ and L=Et₂NH, Pr₂NH, Bz₂NH and (CH₂CH₂OH)₂NH; R=-C₄H₉ and L= Et₂NH and Pr₂NH and where R= C₆H₅ and L= Bz₂NH) were formed. Complexes of the type, R₂SnCl₂.L( where R= -C₆H₅ and L= Et₂NH and Pr₂NH; and where R= -CH3 and L= MePhNH) were also formed. Complexes of the type, ROSnCl₃.2L (where R=-CH₃, -C₂H₅ and t- C₄H₉ and L= Et₂NH, Pr₂NH and Bz₂NH; and also where R= CH₃ and -C₂H₅ with (CH₂CH₂OH)₂NH and MePhNH) were prepared. Complex of the type, ROSnCl₃.L (where R= t-C₄H₉ and L= MePhNH) was also isolated. Infrared spectral studies were carried out.

1 table, 15 ref

020510   Baluja S;Kasundra P;Godvani N (Chemistry Dep, Saurashtra Univ, Rajkot-360 005) : Thermal profile and decomposition kinetics of some new schiff bases of 5-amino isopthalic acid. Acta Cienc Indica-Chem 2008, 34(1), 99-103.

Thermal analysis of some Schiff bases derived from 5-amino isopthalic acid, have been carried out by TG technique. TG data of decomposition have been analysed for the kinetic parameters using Freeman-Carroll method. From the observed curves, various kinetic parameters such as order of degradation (n), energy of activation (E), frequency factor (A) and entropy change (ΔS) have been evaluated. Further, thermal stability of Schiff bases have been determined, which is found to depend on the type of substituent present in the compounds.

5 tables, 20 ref

020509   Balasubramanian K P;Manivannan S;Chinnusamy V (Chemistry Dep, Gobi Arts & Science College, Gobichettipalayam-638 453) : Biological activities of complexes of ruthenium(III) with schiff bases derived from salicylidinephenylenediamine derivatives. J Ultra Chem 2008, 4(1), 15-18.

A new series of mixed ligand hexa coordinated ruthenium(III) Schiff base complexes of the type [RuX₂(B)(L)] (B = PPh₃ or AsPh₃, X= Cl or Br; L= monobasic tridentate Schiff base derived from the condensation of salicylidinephenylene diamine with acetone, acetaldehyde, benzaldehyde) All the complexes have been exhibited to antibacterial study.

1 table, 19 ref

020508   Anbu Srinivasan P;Suganthi M (Chemistry Dep, AVC College (Autonomous), Mayiladuthurai-609 305, Email: panbusrinivas@gmail.com) : Growth and characterization of benzophenone and mixed crystal of benzophenone and 2,4-dinitrophenyl hydrazone of benzophenone. Asian J Chem 2008, 20(3), 1775-80.

Good quality benzophenone crystals were grown by solution technique using CHCl₃ as solvent by adopting slow evaporation method at room temperature. The grown crystals were subjected to various characterization studies to analyze of its purity and applications. The condensation product 2,4-dinitrophenyl hydrazone of benzophenone (DNPBP) was prepared by adopting standard procedure. Then mixed crystal of benzophenone and DNPBP was grown by solution growth. Both the condensation product and mixed crystals were characterized by UV, FTIR. ¹H NMR thermal studies reveals the purity of the product. SHG efficiency of the grown crystals was determined.

1 illus, 13 ref

020507   Al-Anber Z A;Al-Anber M A;Al-Taweel S (Chemical Science Dep, Faculty of Science, Mu tah Univ, P.O. Box 7, Al-Karak 61710, Jordan, Email: masachem@yahoo.com) : Electrochemical behaviour of thienyl-fluorinated-β-diketone substrates and their conductivity in solution. Asian J Chem 2008, 20(3), 1675-90.

The cyclic voltammetric investigations of π-conjugated thienyl fluorinated β-diketone (donor-acceptor moieties) substrates in the acetonitrile solution have been reported. Performed cyclic voltammetry to show the influence of the fluorinated β-diketone substituent on the redox potential of thienyl unit. The cyclic voltammetry curves present one irreversible oxidation potential wave around + 1.88 V. This wave has reported for the thienyl unit. In addition, the curves have one-reversibly redox potential wave (E_1/2), which is related for the fluorinated-p-diketone moiety. This redox wave is found between -1.10 to -1.53 V. Based on the geometrical structures substrates, these waves are discussed. The expected oligomers or dimer has been deposited as solid film. The electrical conduction of thienyl substrates has been evaluated in solution using conductivity. The influence of the substituents on the energy level and energy gap has been calculated using electronic spectra.

9 illus, 2 tables, 31 ref

020506   Ahmad A;Tandon S;Ahmad J;Yadav A (NO, Central Institute of Medicinal and Aromatic Plants, P.O. CIMAP, Lucknow-226 015, Email: aahmadc@yahoo.com) : Chemical composition of the essential oil of Clausena heptaphylla W&A from Assam, India. Asian J Chem 2008, 20(3), 2467-69.

The essential oil obtained by hydrodistillation from the leaves of Clausena heptaphylla (W&A) from Assam, India was analyzed by GC and GC-MS. 16 Compounds representing 97.8% of the total oil were identified of which (E)-anethole (92.6%), (Z)-anethole (1.2%) and methyl chavicol (1.6%) were the major components. Eight minor components were unreported so far.

^ssc1 table, 11 ref

020505   Agrawal O D;Shirkhedkar A A;Surana S J (Pharmaceutical Chemistry Dep, R.C. Patel College of Pharmacy, Shirpur-425 405, Email: atul_shirkhedkar@yahoo.com) : Two UV-spectrophotometric methods for simultaneous determination of levofloxacin and ambroxol in tablets. Asian J Chem 2008, 20(3), 1957-60.

Two simple, rapid, accurate and precise UV-spectropho-tometric methods have been developed for simultaneous estimation of levofloxacin and ambroxol from tablets. Method 1 involves formation and solving of simultaneous equations, while method 2 multicomponent mode of analysis. In distilled water, the absorbance maxima for levofloxacin and ambroxol was found to be 226 and 244 nm, respectively. The linearity was observed in the concentration range of 4-20 μg/ mL for levofloxacin and 4-40 μg/mL for ambroxol. The results of both the methods have been validated statistically and by recovery studies.

2 tables, 10 ref

020504   Abdul Jabbar S;Varma R H K;Sulekha A (P.G. Dep of Chemistry, M.S.M. College, Kayamkulam-690 502) : Stabilisation of Cu(I) by incontestable soft bases leading to the synthesis of environmentally benign clusters-II. Acta Cienc Indica-Chem 2008, 34(1), 13-18.

Ligands N-benzoyl-N'-(phenyl/p-tolyl/p-methoxyphenyl) thiocarbamides were used to synthesise six new environment friendly and bactericidal cluster complexes of Cu(l). The complexes have stoichiometries Cu₄(HL)₂L₄ and Cu4(HL)4L2l2, where HL is the molecule of ligand. The ligands are O, S coordinated and are substantially 'soft'. Complexes Cu₄(HL)₂L₄ have square planar Cu₄ core and the others have tetrahedral core.

2 illus, 3 tables, 7 ref

019576   Zhang Q;Xia Q H;Lu X H;Ma X T;Su K X (Ministry-of-Education Key Laboratory for the Synthesis and Applicatio, Hubei University, Wuhan 430062, China, Email: xia1965@yahoo.com) : Gas-phase catalytic synthesis of MTBE from MeOH and Bu<. Indian J Chem-Sect A 2009, 48(6), 788-92.

Several H-zeolites such as HZSM-5, HY, Hβ, H-13X, H-K₁₀ and HA have been used to catalyze the gas-phase synthesis of methyl tert-butyl ether from methanol and tert-butanol in a continuous fixed-bed reactor. The ascending sequence of Br”nsted acidity is: H-K₁₀ (0.86) < Hb (2.04) < H-13X (2.83) < HY (3.93) < HZSM-5 (5.22), which is appreciably different from the order of Lewis acidity: H-K₁₀ (0.87) < HZSM-5 (1.15) < H-13X (1.75) < HY (4.94) < Hβ (6.10). The optimal reaction temperature varies in the order: Amberlyst-15 (80-110 °C) ≈ Hb (80-90 °C) < HZSM-5 (120 °C) < HY (140-150 °C) < H-K10 (150 °C) << H-13X (220 °C), and is dependent on several factors. The Hβ catalyst shows the best activity and on-stream stability (the selective conversion of >97.4 mol% Bu^tOH to MTBE) at 80-90 °C (comparable to that of commercial Amberlyst-15), along with increasing time-on-stream up to 110 h at 90 °C. The highly selective conversion of Bu^tOH to MTBE remains more or less constant on both the catalysts.

019575   Yang X D (School of Medicine, Jinhua College of Profession and Technology, Jinhua, Zhejiang, 321017, P.R. China, Email: jhyangxd@gmail.com) : Synthesis and characterization of some novel thiourea having sugar and 1,3,4-thiadiazole moieties. Asian J Chem 2008, 20(2), 1551-5.

Several novel 1,3,4-thiadiazole thioureas have been prepared by the condensation of hepta-O-acetyl-β-D-glucosyl isothiocyanate with 2-amino-5-substituted-1,3,4-thiadiazoie. The structures of these new N-glucosides have been established on the basis of ¹H NMR, mass spectral and elemental analysis studies.

2 tables, 25 ref

019574   Yaiphaba N;David Singh T;Indira Devi M; Rajmuhon Singh N (Chemistry Dep, Manipur Univ, Imphal-795 003) : Calculation of energy interaction parameters for the complexation of Pr(III) and Nd(III) with 1,10-phenanthroline and 2,2'-bipyridyl by 4f-4f absorption spectral analysis. Asian J Chem 2008, 20(2), 901-14.

Absorption difference and comparative absorption spec-troscopic studies involving 4f-4f transitions on Pr(III) and Nd(III) with structurally related 1,10-phenanthroline and 2,2'-bipyridyl complexes in DMF, CH₃CN, dioxane, CH₃OH and their equimolar mixtures have been carried out. Variations in the spectral energy parameters like Slator Condon (F_K), Lande spin orbit coupling (ξ_4r), nephelauxetic ratio (β) and bonding parameter (b^1/2) and per cent covalency (δ) are calculated and correlated with the interaction of Pr(III) and Nd(III) with 1,10-phenanthroline and 2,2'-bipyridyl. The marginal decrease in the values of F_K and ξ_4f, are correlated with the increase in the value of (3. The difference in the energy parameters with respect to donor atoms and solvents reveal that the chemical environment around the lanthanide ion has great impact on /-/ transition and any change in the environment results in modifications of the spectra.

1 illus, 2 tables, 24 ref

019573   Yadav T K;Satyendra Singh (Electrochemical Laboratory, Kashi Naresh Government Post Graduate College, Gyanpur, Sant Ravi Das Nagar, Bhadohi-221 304) : Determination of stability constants of some metal mixed complexes in solution by solution electophoresis [Be(II), Mn(II), Pb(II), Cd(II)-methyl cysteine-NTA system]. Asian J Chem 2008, 20(2), 870-8.

An innovative solution electrophoresis technique has been used for the study of mixed ligand complexes of some divalent metals ions viz., Be(II), Mn(II), Pb(II) and Cd(II) with methyl cysteine as primary ligand and NTA as secondary ligand. The stability constants of the mixed complexes formed were found to be: 4.81, 4.67, 3.54, 3.65 (log k values) for Be(II), Mn(II), Pb(II) and Cd(II), respectively at 30 ± 0.5 °C an ionic strength 0.1 M.

3 illus, 18 ref

019572   Yadav B S;Singhal S;Subhash;Chand S (Molecular Spectroscopy and Biophysics Laboratory, Deva Nagri Postgraduate College, Meerut-250 001) : Electronic absorption spectra of 5,7-dibromo-8-hydroxy quinoline. Asian J Chem 2008, 20(2), 925-8.

The present paper presents the electronic absorption spectra of 5,7-dibromo-8-hydroxy quinoline. The effect of solvents viz., ethanol, methanol and water has also been studied and discussed on the electronic transitions of the said molecules. The spectra have been recorded in the region 1900-4000 Angstrum. The transitions have been identified as ^{1A' →1A' under the Cs symmetry of the molecules studied, corresponding to 1B_su → 1A_g transition.}

1 illus, 1 table, 19 ref

019571   Vyas D H;Tala S D;Akbari J D;Dhaduk M F;Joshi K A;Joshi H S (Chemistry Dep, Saurashtra University, Rajkot-360 005) : Synthesis and antimicrobial activity of some new cyanopyridine and cyanopyrans towards Myco-bacterium tuberculosis and other micro-organisms. Indian J Chem-Sect B 2009, 48(6), 833-9.

2-Amino-3-cyano-6-(3,5-dibromo-4-methoxyphenyl)-4-aryl-pyridines 2a-i are synthesized by the reaction of compounds (2E)-3-(3,5-dibromo-4-methoxyphenyl)-1-arylprop-2-en-1-one 1a-i with malononitrile in the presence of ammonium acetate. Condensation of compounds 1a-i with malononitrile in pyridine has yielded 2-amino-3-cyano-6-(3,5-dibromo-4-methoxyphenyl)-4-arylpyrans 3a-i. The constitution of all the synthesized compounds have been established by elemental analyses, IR, ¹H NMR, and mass spectral data. All the compounds are screened for their antitubercular and antimicrobial activities.

019570   Vidyalakshmi K S;Rajamanickam G V (Chemistry Dep, PRIST University, Thanjavur, Tamilnadu) : Iridoid with anticancer activity from the sepals of Mussaenda 'dona aurora'. Indian J Chem-Sect A 2009, 48(7), 1019-22.

A new cytotoxic iridoid glycoside and a number of known flavonols and iridoids have been reported.

019569   Vessally E;Nikoorazm M;Afashar H G;Mohsenpour T (Science Dep, Payame Noor Univ, Zanjan Branch, Zanjan, Iran, Email: e_vesali@yahoo.com) : Singlet-triplet energy gaps in divalent C₂H₂M and C₂H₆M (M = C, Si, Ge, Sn and Pb). Asian J Chem 2008, 20(2), 1121-9.

Singlet-triplet energy gaps in cyclopropeneylidene, 1_c, and propaneylidene, 2_C, are calculated and compared with their analogues 1_M and 2_M (M = SL_-s vs. Si_-1), (M = Ge_-s vs. Ge_-t), (M = Sn_-s vs. Sn_-t) and (M = Pb_-s vs. Pb_-t); at B3LYP/6-311++G** level of theory. The change order of energy gaps between triplet (t) and singlet (s) states, ΔG_t-s for 1_M is: 1_S > 1_c > 1_Ge > 1_sn > 1_pb while for 2_M, the opposite order is obtained: 2_Pb > 2_Sn > 2_Ge > 2_Si > 2_C (calculated via B3LYP/6-311++G**). Energy gaps, IG_t-s, of 1_M and 2_M appear linearly proportional to the size of the group 14 divalent elements (M) and the ∠ C-M-C angle.

2 illus, 4 tables, 28 ref

019568   Verma R;Bhatnagar U;Jain P;Singh S C;Pathak V (Chemistry Dep, I.B.S., Fr B.R.A. University, Agra-282 002) : Synthesis and characterization of copolymer of furan and acrylonitrile. Int J chem Sci 2007, 5(1), 217-22.

Vinyl compound containing copolymer films have been synthesized by copolymerization of furan with acrylonitrile intiated by AIBN (α α' - Azobis isobutyronitrile). Their properties viz. electrical conductance, solubility, chemical resistance, permeability, softening range and molecular weight have been studied. The synthesized copolymers were characterized by ¹H NMR and IR specrtoscopy. The copolymers were found to be highly electroconducting in nature. Average molecular weight of all the synthesized copolymers films were determined by cryscopic method. Characteristic features of the copolymers was that they have no definite melting points but melt within a certain temperature range.

1 illus, 2 tables, 9 ref

019567   Venkateswara Rao G;Sambasiva Rao K;Annamalai T;Mukhopadhyay T (NO, CavinKare Research Centre, 12, Poonamalle Road, Ekkattuthangal, Chennai-600 032) : New coumarin diol from the plant, Chloroxylon swietenia DC. Indian J Chem-Sect A 2009, 48(7), 1041-44.

A new coumarin diol has been isolated from the chloroform fraction of the leaves of the plant, Chloroxylon swietenia DC. The structure of new compound has been established as 6-(2', 3'-dihydroxy-3-methylbutyl)-8-prenylumbelliferone based on the spectral (UV, IR, ¹H, ¹³C and 2D NMR and mass) data.

019566   Valecha S;Mangaokar K (Chemistry Dep, K.C. College, Churchgate, Mumbai-400 020, Email: r_valecha@rediffmail.com) : Mixed ligand chelates of transition metal ions with [(1-phenyl-3-methyl-5-oxodihydropyrazol-4-yl)phenylimino]-2',3'-dimeth ylaniline as a primary ligand and 2-hydroxy-1-naphthaldehyde as a secondary ligand. Asian J Chem 2008, 20(2), 967-72.

Binary and ternary complexes of the type M-Y and M-X-Y [M = Cu(II), Zn(II), Mn(II), Ni(II), Co(II), X = [1 -Phenyl-3-methyl-5-hydroxopyrazol-4-yl)phenylimino]-2',3'-dimethyl-ani line, Y = 2-hydroxy-1-naphthaldehyde have been examined pH metrically at 29 °C and μ = 0.1 M (KCl) in a (75:25) % (v/v) dioxane-water medium. The values of formation constants for M-Y and M-X-Y systems [M = Cu(II), Zn(II), Ni(II), Co(II), Mn(II)] are calculated.

2 illus, 4 tables, 8 ref

019565   Tripathi P (Chemistry Dep, St. Andrews College, Gorakhpur-273 001, Email: praveen_chem97@rediffmail.com) : Synthesis and antifungal activity of some substituted pyrazolo[4,5-e]pyrimidines derivatives. Asian J Chem 2008, 20(2), 1654-6.

1-Aroyl-5-aryl-4-oxo-6-thio-pyrazolo[4,5-e]pyrimidines have been synthesized. The newly synthesized compounds showed antifungal activity against Aspergillus niger and Aspergillus flavus.

1 table, 12 ref

019564   Thomas K K;Reshmy R (Chemistry Dep, Bishop Moore College, Mavelikara-690 110, Email: reshdevu_pk@yahoo.co.in) : Bioactive 2-sustituted amino-5-benzothiazol-2-oyl-4-phenylthiazoles. Asian J Chem 2008, 20(2), 1457-63.

Amino or substituted aminothiazoles exhibit bacterial, fungicidal, herbicidal and pesticidal properties. The (4+1) thiazole construction strategy adopted involves the synthesis of the [C-N-C-S] precursors, namely l-aryl-3-(N-phenyl-benzimidoyl)thiourea or 1-alkyl-3-(N-phenylbenzimidoyl)-thiourea and the preparation of the C5 synthone, the halo acetylhetaroyl derivative. The optimized reaction conditions developed have thus lead to the preparation of five 2-(N-aryl-amino)-5-(benzothiazol-2-oyl)-4-phenylthiazoles and three 2-(N,N-dialkylamino)-5-(benzothiazol-2-oyl)-4-phenylthia-zoles. The structure of these compounds were assigned on the basis of elemental analysis, FTIR, ¹H NMR and ¹³C NMR and screened for their antimicrobial activity.

11 ref

019563   Thakur S (Chemistry Dep, School of Applied Sciences, Netaji Subhash Institute of Technology, Sector-3, Dwarka, New Delhi-110 073, Email: sanjeevethakur63@yahoo.co.in) : Calorimetric studies of the acetates of calcium(II), strontium(II) and barium(II). Asian J Chem 2008, 20(2), 1645-7.

From experimentally measured enthalpies of combustion of Ca(II), Sr(II) and Ba(II) acetates, their standard enthalpies of formation were determined as -1488, -1496 and -1492 kJ. mol^-1, respectively. The metal-oxygen mean bond dissociation energy values were also estimated.

^ssc1 illus, 1 table, 7 ref

019562   Teimuri-Mofrad R;Abrishami F (Chemistry Dep, Faculty of Materials, Malek-ashtar Univ of Technology, Tehran, P.O. Box 16765-3454, Iran, Email: teimuri@mut.ac.ir) : Synthesis of some hydroxymethyl derivatives of 4H-pyran-4-ones via N-O bond cleavage. Asian J Chem 2008, 20(2), 1203-10.

A new method was developed for the synthesis of hydroxymethyl derivatives of 4H-pyran-4-ones from corresponding phthalimidoxymethyl derivatives by reduction of N-O bond with zinc powder and hydrochloric acid. These phthalimidoxymethyl derivatives of 4H-pyran-4-ones were synthesized by means of reactions of their bromomethyl derivatives and N-hydroxyphthalimide.

3 illus, 6 tables, 8 ref

019561   Tavallali H;Sheikhaei M (NO, Payame Noor University (PNU), Shiraz, 71365-944, Iran, Email: tavallali@pnu.ac.ir) : Simultaneous kinetic determination of paracetamol and caffeine using Cu(II)-neocuproine in presence of dodecyl sulfate by H-point standard addition method. Indian J Chem-Sect A 2009, 48(6), 812-6.

A simple, feasible and selective kinetic spectrophotometric method for simultaneous determination of paracetamol and caffeine using H-point standard addition method is described. The method is based on difference in the rate of oxidation of the compounds with Cu(II)-neocuproine system and formation of Cu(I)-neocuproine complex, which is monitored at 453 nm and at pH 5.0 in the presence of sodium dodecyl sulfate. Experimental conditions such as pH, reagents concentrations, ionic strength and temperature have been optimized. Paracetamol and caffeine can be determined in the range 1.5-7.0 and 0.1-3.0 μg ml^-1 respectively. The proposed method has been applied for the determination of paracetamol and caffeine in pharmaceutical samples with satisfactory results.

019560   Tasneem K;Khan K Z (Chemistry Dep, North Eastern Regional Institute of Science & Technology, Itanagar-791 109, Email: khalidatasneem@rediff.com) : Dimethyl sulphoxide-acetic anhydride: an excellent source of formaldehyde and thiomethanol. Asian J Chem 2008, 20(2), 929-33.

The reaction between DMSO and Ac₂O at water bath temperature yield formaldehyde and thiomethanol when exposed to this modified reagent. β-diketone and β-naphthol react with formaldehyde to give corresponding methylene-fcw-deriva-tives and thiomethanol acting as Micheal donor reacts with compound (3Z)-3-(2-hydroxybenzylidine)-2W-chromene-2,4(3H)-dione (7) to give an adduct 4-hydroxy-3[(2-hydroxy-phenyl)(methylthiomethyl)]-2H-chromene-2-one (9) exposure of 7 to thiophenol give 4-hydroxy-3-[(2-hydroxyphenyl) (phenylthiomethyl)]-2H-chromen-2-one(10).

6 ref

019559   Tambatkar G D;Meshram Y K;Saoji V;Raut H M (Chemistry Dep, G.S. College, Khamgaon-444 312, Email: tambat_kar@rediffmail.com) : Stability constant of Ce(II), Pr(III) and Tb(III) chelates with some substituted drugs. Asian J Chem 2008, 20(2), 1095-8.

The interaction of Ce(III), Pr(III) and Tb(III) metal ions with cefadroxyl or 8-[2-amino-2-(4-hydroxylphenyl)acetyl]-amino-4-methyl-7-oxo-2-thia-6-a zobicyclo[4,2,0]oct-4-ene 5-carboxylic acid (ligand-1), deoxycycline or 4-(dimethyl-amino)-1,4,4a,5,5a,6,11,12a-octahydro-3,6,10,12,12a-penta- hydroxy-1,11 -dioxonaphthene-2-carboxamide (ligand-2) and dexamethasone or 9-fluro-11β, 17,21 -trihydroxy-16a-methyl-pregna-14-diene-3,20-dione (ligand-3) have been investigated by pH-metric technique at 0.1 M ionic strength and at 27 ± 0.1 °C in 70 % DMF-water mixture. The data obtained were used to estimate the values of proton-ligand stability constant (pK) and metal ligand stability constants (log K). It is 1:1 and 1:2 complexes with all the three ligands.

3 tables, 8 ref

019558   Swami M B;Pachling S P;Akuskar S K (NO, B.S. College, Basmathnagar-431 512) : Coordination complexes of propiophenone derivatives and Sm(III). Int J chem Sci 2007, 5(1), 95-102.

The proton-ligand and metal-ligand stability constant of Sm (III) with 3-chloro, 2-hydroxy propiphenone [L₁] have been evaluated using potentiometric measurement.

4 illus, 1 table, 16 ref

019557   Sureshbabu V V;Chennakrishnareddy G (Peptide Research Lab, Studies in Chemistry Dep, Central College Campus, Dr. B. R. Ambedkar Veedhi, Bangalore University, Bangalore-560 001) : HOAt.DCHA as co-coupling agent in the synthesis of peptides employing Fmoc-amino acid chlorides as coupling agents: Application to the synthesis of β-casomorphin. Indian J Chem-Sect A 2009, 48(7), 981-8.

Racemization free protocol for the synthesis of peptides employing Fmoc-amino acid chlorides mediated by HOAt.DCHA as co-coupling agent has been described.

019556   Sundaramoorthi P;Kalainathan S;Shajitha Banu A (Physics Dep, Mahendra Engineering College, Mallasamuduram, Namakkal-637 503, Email: sundara78@rediffmail.com) : Barium magnesium hydrogen phosphate single crystal growth in silica gel medium: characterization studies and laser irradiated nucleation reduction process strategy. Asian J Chem 2008, 20(2), 863-9.

In the chemical reaction method, barium magnesium hydrogen phosphate (BMHP) crystals are grown in silica gel medium using different gel densities and various concentrations of orthoposphoric acid and supernatant solutions. The gel pH gives an important role in the formation of different H₃PO₄ species in the phosphoric system, the pH range in which HPO^-2₄ ions dominates were considered, which in turn is necessary for the growth of BMHP crystals. The characteristics of well grown crystals are carried out by FTIR, TGA/ DTA, SEM, XRD and etching.

2 illus, 4 tables, 22 ref

019555   Srivastava S;Singh S (Chemistry Dep, Feroze Gandhi College, Raebareli-229 001, Email: she_ila72@yahoo.com) : Kinetic study of Rh(III) catalyzed oxidation of sucrose by sodium periodate in acidic medium. Asian J Chem 2008, 20(2), 973-8.

The kinetics of rhodium(III) catalyzed oxidation of sucrose by sodium periodate in acidic medium has been studied in the temperature range 30-50 °C. The reaction is carried out in the presence of mercuric acetate as a scavenger for bromide ion. The rate shows first order kinetics with respect to the oxidant i.e., sodium periodate and Rh(III) for sucrose. Negligible effect of mercuric acetate and ionic strength of the medium was observed and the reaction showed no effect of [Cl^-] and [H⁺] on the reaction rate for sucrose. A suitable mechanism in conformity with the kinetic observations has been proposed and the thermodynamic parameters computed.

2 illus, 3 tables, 24 ref

019554   Srivastava J;Khare A;Khare N K (Chemistry Dep, University of Lucknow, Lucknow-226 007) : Synthesis of blocked trisaccharide analogue related to the repeating unit of the O-antigen from E. coli : 025. Indian J Chem-Sect B 2009, 48(6), 848-52.

019553   Srinivasan S;Savarianandam A;Gnanapragasam S; Gunasekaran S;Krishnamoorthy G (Physics Dep, Aarupadai Veedu Institute of Technology, Paiyanoor-603 104, Email: dr_s_srinivasan@yahoo.com) : Charge density and solvation studies of benzoxazole and its derivatives-2-phenyl benzoxazole and 4-amino-2-phenyl benzoxazole. Asian J Chem 2008, 20(2), 1055-62.

Biologically important molecules benzoxazole and its derivatives 2-phenyl benzoxazole and 4-amino-2-phenyl benzoxazole were investigated theoretically using molecular orbital and density functional theory. Semi empirical MO calculations, AM1 procedure, have been carried out on these molecules. These include charge density, heat of formation, ionization potential, highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies and energy gaps. Solva-tion analysis on these compounds have been carried out by the polarizable continuum model (PCM) at the B3LYP with 6-31G* level of theory. The effects of electrostatic and non-electrostatic interaction contribution to free energy of solvation were discussed.

3 illus, 5 tables, 27 ref

019552   Srinivasan B R;Naik A R;Nather C;Bensch W (Chemistry Dep, Goa University, Goa-403 206, Email: srini@unigoa.ac.in) : Synthesis and structural characterization of bis(n-propylammonium) tetrasulfidometalates. Indian J Chem-Sect A 2009, 48(6), 769-74.

The reaction of (NH₄)₂[MS₄] (M = W, Mo) with n-propylamine (CH₃-CH₂-CH₂-NH₂) results in the formation of bis(n-propylammonium) tetrasulfidometalates (CH3-CH₂-CH₂-NH3)₂[MS₄] (M = W (1); Mo (2)). Both compounds have been characterized by elemental analysis, IR, Raman and UV-vis spectra and crystal structures. Compounds (1) and (2) are isostructural and crystallize in the centrosymmetric orthorhombic space group, Pnma. The structure consists of discrete slightly distorted tetrahedral tetrasulfidometalate [MS₄]^2- anions of m symmetry, separated by two crystallographically independent n-propylammonium cations located on mirror planes. The carbon atoms of the organic cations are disordered. A comparative study of twelve tetrasulfidometalates crystallizing in the orthorhombic space group Pnma is presented.

019551   Snigdha Chanda;Ismail K (Chemistry Dep, North Eastern Hill University, NEHU Campus, Shillong-793 022, Email: kismail@nehu.ac.in) : Surface potential and polarity at the micelle-solution interface in AOT + water system. Indian J Chem-Sect A 2009, 48(6), 775-80.

Surface potential of sodium dioctylsulfosuccinate (AOT) micelles (a double-chained anionic surfactant with special properties), in aqueous medium near the critical micelle concentration has been computed by solving the Poission-Boltzmann equation and is found to be -117 mV. The effective dielectric constant at the water - AOT micelle interface has been determined spectrophotometrically by using different probes and is estimated to be ~ 54 ± 4. The polarity determined at the micellar interfaces shows dependence on the probe used, which is considered to be due to different solubilization sites for different probes. Methyl red and pyrene probes are not found to be suitable for estimating the dielectric constant.

019550   Singh S S;Singh V K;Singh S (Chemistry Dep, Kashi Naresh Government Post Graduate College, Gyanpur, Sant Ravi Das Nagar, Bhadohi-221 304) : Electo chromatographic study of some metal complexes in solution [Cu(II)/Ni(II)/Co(II)/Zn(II)-8-azaguanine-system]. Asian J Chem 2008, 20(2), 934-8.

A modified electro chromatographic method has been developed for the study of 8-azaguanine complexes of some divalent metal ions viz., Cu(II), Ni(Il), Co(II) and Zn(II). 1:1, 1:2 Complexes are formed with each metal ions. The stability constant were determined at ionic strength 0.1 M perchloric acid.

2 illus, 1 table, 8 ref

019549   Singh R P;Tomer A S;Arora S K;Chaudhary R (Chemistry Dep, S.G. (P.G.) College, Sarurpur-Khurd, Meerut-250 344) : Interaction between steroids and proteins. Asian J Chem 2008, 20(2), 1039-48.

The binding oicholesterol and its stearate ester was studied with soluble ovalbumin and Transfusion gelatin using partition and dialysis equilibrium methods. The intrinsic association constants and binding sites were found to be pH and temperature dependent. The linear nature of binding plots suggests the involvement of single one class of sites in the interaction. The binding was found to be maximum in the physiological pH range while lesser at pH 11.5, which was ascribed to protein denaturation. Approximately similar values of log K at all pH values suggested the involment of identical sites in steroid-protein interaction.

3 illus, 4 tables, 45 ref

019548   Singh R P;Tomer A S;Arora S K;Chaudhary R (Chemistry Dep, S.G. (P.G.) College, Sarurpur-Khurd, Meerut-250 344) : Binding of naphthofuran derivatives to bovine serum albumin by distribution experiments. Asian J Chem 2008, 20(2), 1032-8.

The interaction of 2-phenyl-3-p-(β-pyrrolidins)ethoxy-phenyl naphthofuran hydrochloride with N,N-diethyl amino derivative to bovine serum albumin (BSA) at pH 7.4 was studied applying partition method. A comparision of binding constants of two types of compounds indicated stronger combination with N,N-diethyl amino derivative than that of pyrrolidine derivative. The intrinsic association constants being 1.62 x 10³ with former and 1.53 x 10³ for the later, respectively. The solvents used for the distribution experiments do not play any significant role deciding the extent of ligand-BSA interactions. The data indeed revealed that the value of n, K and AP was the same for bovine serum albu-min either from toluene or from n-octyl alcohol.

5 illus, 3 tables, 16 ref

019547   Singh P K;Siddiqui I R (Laboratory of Green Technology, Chemistry Dep, University of Allahabad, Allahabad-211 002) : New versatile strategy for design and synthesis of reduced risk fungicides: Bibenzyl core incorporated with modified as-indacene. Indian J Chem-Sect A 2009, 48(7), 1013-18.

A novel montmorillonite K 10 clay catalyzed Michael addition followed by dehydrative cyclization in one-pot is designed to synthesize 4,4'-bis(4",8"-aryl-1",4"-dihydro-bisthia-zolo-[3,2-a;5'",4'"-e]pyrimi dine-2"-thion-1"-yl)biben-zyls 6a-j with excellent yield under microwave irradiation in solvent-free conditions. Antifungal screening results on Fusarium oxysporum and Penicillium citrinum show that most of the synthesized compounds display promising antifungal activity.

019546   Sharma B K;Singh P;Sharma S (Engineering Chemistry Dep, Sobhasaria Engineering College, Sikar-332 001, Email: psingh_sikar@rediffmail.com) : Quantitative structurde-activity relationship study of the derivaties of 4-(ω-(alkyloxy) alkyl)-1H-imidazole as histamine H₃ receptor antagonists. Int J chem Sci 2007, 5(1), 165-74.

The antagonistic activities of derivatives of 4-(w-(alkyloxy)alkyl)-IH-imidazole as the histamine H₃ receptor is quantitatively analyzed employing physicochemical parameter, the molar refraction parameter MR. This parameter, accounting for the polarizability and/or steric bulk of the substituents, was initially correlated linearly with pK_j values of the compounds. However, the plot of MR versus pK_j showed a parabolic trend among them. Thus, a parabolic regression equation was derived whose statistical parameters were more reliable in comparison to that of linear correlation equation. The plot and the parabolic relationship further helped in tracing the 'outlier' congener of the series. Elimination of this compound improved the parabolic equation significantly, but the highest significant correlation equation was obtained through the bilinear model. From this model equation, it was interpreted that only a substituent having an optimum MR_o = 3.818 may results into the highest pK_j value while the other substituents with their molar refraction values less than or greater than 3.818 can not attain the highest activity value pertaining to histamine H3 receptor. The analysis, in this way, provided the ground for rationalizing the substituent selection in designing better potency compounds of the series.

3 illus, 1 table, 27 ref

019545   Sharma B K;Sharma S K;Singh P;Sharma S (Chemistry Dep, S.K. Government College, Sikar-332 001, Email: psingh_sikar@rediffmail.com) : A quantitative structure-activity relationoship study of Na<. Int J chem Sci 2007, 5(1), 281-9.

The Na⁺/H⁺ exchanger isoform-l (NHE-I) inhibitory activity of (5-arylfuran-2-ylcarbonyl) guanidine derivatives is quantitatively analyzed using multiple regression analysis. The analysis has helped to ascertain the role of different substituents in explaining the observed inhibitory activity of these compounds as cardioprotective agents. It was concluded from derived most significant correlation equation that 2- and 5-substituents that are more hydrophobic in nature are advantageous for a compound to elicit higher inhibitory activity. Similarly a substituent at 4-position having smaller value of dipole moment is also beneficial. However, a Me substituent at 5-position is unfavorable. Such a study, therefore, provided the ground for rationalizing the selection of substituent in designing more potent compounds of the series.

2 illus, 2 tables, 15 ref

019544   Shanmugapandiyan P;Ramesh A (Analytical chemistry Dep, International Institute of Biotechnology and Toxicology, Padappai-601 301, Email: raamesh_a@hotmail.com) : Synthesis and antimicrobial activity of 1-(Benzothiazol-2'-yl)-5-phenyl-tetrazole. Asian J Chem 2008, 20(2), 992-8.

In the study, a new series of l-(benzothiazol-2'-yl)-5-phenyl-tetrazole were synthesized by the reaction of Schiff base (2-aminobenzothiazole and substituted benzal-dehyde) with phosphorous pentachloride and sodium azide. The chemical structures of the synthesized compounds were confirmed by means of IR, ¹H NMR, mass spectral and elemental analysis. The synthesized compounds were screened for antibacterial (Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosd), antifungal (Aspergillus niger and Candida albicans). The synthesized compounds exhibited good antibacterial and significant antifungal activity at the dose of 250 pg/mL by Paper disc diffusion method.

1 table, 22 ref

019543   Shagufta;Singh R;Panda G (Medicinal and Process Chemistry Div, Central Drug Research Institute, Mahatma Gandhi Marg, Lucknow-226 001) : Synthetic studies towards steroid-amino acid hybrids. Indian J Chem-Sect A 2009, 48(7), 989-95.

019542   Seza Bastug A;Gokturk S;Sismanoglu T (Chemistry Dep, Faculty of Engineering, Istanbul Univ, 34850, Istanbul, Turkey, Email: tusase@istanbul.edu.tr) : 1:2 binary complexes of citric acid with some metal ions: stability and thermodynaimc parameters. Asian J Chem 2008, 20(2), 1269-78.

The stability constants of the 1:1 binary complexes of citric acid with Cu²⁺, Ni²⁺, Co2⁺, Mn²⁺ and Ce³⁺ were determined potentiometrically at 15.0, 25.0 and 35 °C and at an ionic strength of 0.10 mol L^-1 (NaClO₄). UV-Vis spectroscopic studies were also performed in order to confirm the complex formation and the stability constants of Cu-citric acid system determined potentiometrically. The thermodynamic parameters, ΔG°, Δ H ° and ΔS° were reported for the complexes formation reactions. The enthalpy and entropy changes of all binary complexes are positive.

6 illus, 4 tables, 9 ref