Rafidain Journal of Science

A rapid, sensitive and accurate method for the determination of substituted oxadiazol (I&II) has been developed based on the reduction of electroactive group (-C=S) at hanging mercury electrode by using square wave voltammetric technique. The reduction peaks obtained at –0.028 and –0.172 V Vs Ag/AgC1 fir compounds I & II respectively at pH 2 in Britton – Robinson buffer are recommended for the trace determination of these compounds. Regression analysis on standard curve indicated a linear relationship between peak current and concentration over the rang 1.2  10-6–2.5  10-5 M with a correlation coefficient of more than 0.98.

A spectrophotometric method for the trace determination of sulphamethazine has been worked out. It is based on the reaction of sulphamethazine with sodium nitrite in acidic medium to form the corresponding diazonium salt. After removal of excess nitrite with sulphamic acid, the diazotised sulphamethazine is coupled with m-aminophenol fo form an intensely-yellow coloured, water-soluble and stable azo dye which shows maximum absorption at 457 nm. The plot of absorbance versus determinand concentration shows that Beer’s law is obeyed over the concentration range 5-150 g sulphamethazine/25 ml final volume, i.e., 0.2-6 ppm with a molar absorptivity of 4.8X104
l.mol-1.cm-1. The method has been applied to the assay of the drug in a tablet.

Some new heterocyclic compounds of 1,2,4-oxadiazolidine-5-one derivatives
[3a-m] were synthesized from the reaction of nitrone compounds with some isocyanates of amino acid esters in good yields.
The reaction of nitrone compounds with cyclooctene and tetrahydrophthalic anhydride gave oxazolidine derivatives [4a-d]. The synthesized compounds were formed via 1,3-cycloaddition reaction of isocyanates and alkenes to nitrones. The I.R. spectral data of the synthesized compounds were also discussed.

We have measured the electrical conductivity of a mixture of both symmetrical and unsymmetrical complexes: {[Ni(en)3](N03)2} + {[Co(en)2Cl2]Cl} in methanol at 298K. The results are analysed using Lee-Wheaton equation. The equivalent conductivities have been compared with the experimental values at the best-fit values of (R) and they are found to be in a good agreement. Besides, we have calculated the ionic concentration, activity coefficient, transport number for each ion present in the solution.

The research was concerned with biochemical studies in serum of duodenal ulcer (DU) patients. The present study included (152) patients (105 males and 47 females), their ages ranged between (15-56) years, attending endoscopy unit of Al-Razzi General Teaching Hospital in Ninevah Governorate.
Blood samples from (152) DU patients, were collected for some biochemical parameters including alkaline phosphatase (ALP), glutamate pyruvate transaminase (GPT), urea, total protein, Immunoglobulins (Igs), and haemoglubin (Hb).
The results predicted that GPT, urea, total protein, IgG and complement C4 statistically showed no significant difference with H. pylori infection, while ALP, IgM, IgA, complement C3 and Hb showed significant differences.

A number of substituted malonamic acids derivatives were prepared by nucleophilic substitution reactions of substituted malonyl chlorides with phenyl carbamate followed by reaction of the products with water, alcohol and amine. The structures of the synthesized compounds were elucidated by physical and spectroscopic methods.

alkaline phosphatase (ALP) and albumin was studied on twenty seven rachitic children aged 6-60 months who attended the outpatient department in Al-Khansa maternity and children's Hospital in Mosul during the period from July 2000 to April 2001 and were followed up 6-8 weeks after treatment by oral massive single dose of vitamin D . The radiological and biochemical characteristics of cases ware ascertained before and after therapy .The biochemical changes ware analyzed by student (t) test.
There was a significant increase in the level of serum calcium(p<0.006), phosphorus, and albumin (P<0.0001), with a significant decrease in the ALP activity after vitamin D therapy with no risk of hypercalcaemia (P< 0.0001).
In conclusion, ALP is the main test in the follow up of rachitic children ,also oral massive single dose of vitamin D is effective in reversal of BBP to normal levels with no risk of hypercalcaemia
Key words: Rickets, Calcium, Phosphorus, Albumin, Alkaline phosphatase, Biochemical Bone Profile, Vitamin D.

A simple, rapid and sensitive spectrophotometric method for the determination of micro amounts of salbutamol sulphate in aqueous solution has been developed. The method is based on the coupling of salbutamol sulphate with diazotised p-nitroaniline in basic medium to form a coloured mono azo dye which is stable, water- soluble and exhibits maximum absorption at 488 nm. Beer’s law is obeyed over the range 10–120 g of salbutamol sulphate in a final volume of 25 ml, i.e., 0.4–4.8 ppm with a molar absorptivity of 3.13104 l.mol.-1cm-1, a relative error of +1.80 to –3.40% and a relative standard deviation of +5.70 to +1.65%, depending on the concentration level. The proposed method does not require temperature control or solvent extraction and the method has been successfully applied to the determination of salbutamol sulphate in different types of pharmaceutical preparations, tablets and syrup.

The study involved investigation of the adsorption of aromatic carboxylic acids carrying various substituents such as OH, NH2 and SH. The effects of concentration, temperature and pH were induced. The results indicated that increasing the temperature from 15 to 30 oC reduces the adsorption ratio, while dilution of carboxylic acid solution to a little value showed high adsorptivity. This point is of a valuable interest because most of carboxylic acids as pollutants present in a minute amounts.
Effect of pH showed that the natural pH is the best condition for the removal which is arreptable for the treatment of industrial water. According to the literature we assumed that after one hour of extraction the system will be in equilibrium. Therefore, from this point we determined the thermodynamic functions for each system under investigation. The study revealed that the hydrogen bond present in the system and other attraction forces with the resonance have great effect on the adsoption.

Salicylidene aliphatic amines in cyclohexane form 1:1 charge transfer complexes on addition of Eu(fod)3, indicated by the observation of a new band in their U.V. spectra located at longer wavelength (= 400 nm) and with low extinction coefficient. The coulorless solutions of Schiff-bases were changed to yellow on complexation with the shift reagent Eu(fod)3.
Equilibrium Constant values (K) for the complexes were obtained by applying Benesi-Hildebrand equation. The factores which affected the values of of K like the charge on N, O & C (ChN, ChO, ChC), steric energy, O-N distance, the dihedral angles (dh1 and dh2) were established computationaly and were inserted into an equation of multiple linear regression as independent variables with K as dependet variable:

K= -1288.806-1653.722ChN-40.197ChO-914.560ChC+507.207(O-N dist.)

From the equation it is seen that the most effective factor is ChN which means that increasing ChN causes more availability of the lone pair of electrons on nitrogen which facilitate the interaction with Eu(fod)3 and thus leading to higher K-value.

The study of -radiolysed natural Iraqi silica (Ninivite) as obtained from the main rocks indicated that as we increase the irradiation time, the ratio of amorphous silica to the crystalline one is increased. A significant effect is recognized when irradiation time approximately two hours. The radiation causes cleavage of the polymeric structure of the silica and produce monomeric silica of amorphous type. The application of the irradiated silica to the separation of virgin olive oil indicates a large difference between one fraction and another as shown by the amount of fractions and I.R. measurements. I.R. measurements indicate that olive oil contains fatty acids, fatty acid esters, phenols, alcohol and some other minor components.

The paper reports a sensitive and rapid method for the measurement of Lactate Dehydrogenase activity (EC 1.1.1.27) in human serum. The method is based on the polarographic measurement in the reduction of polarographic peak of NAD+ via the enzymatic reaction of LDH with lactate and NAD+.
The method was successfully applied to measure LDH activity in serum of normal and diseased individuals after the removal of albumin by zinc acetate method.

The synthesis of azo compounds (9-11) has been achieved by reaction of diazonium salts of substituted 4`-aminosulfonanilides with some aromatic amines or phenols 4-Nitroaniline (1) is served as a synthon for 2,6-dibromo-4-nitroaniline (6). The compounds (1 and 6) undergo sulfonylation with methane- and 4-toluene sulfonyl chloride to give the corresponding sulfonanilides (2, 3, 7). The nitro group in these compounds is reduced to amino group to produce compounds (4, 5, 8). These compounds are diazotised to the corresponding diazonium salts, which are coupled with different aromatic amines or phenols to produce the azo compounds (9-11). The structure of the synthesized compounds has been confirmed on the basis of physical and spectral measurements

Tin, selenium and bismuth metal complexes containing Schiff bases ligands derived from ortho-benzaldehyde, dimethyl ketone, diethyl ketone and di(o-aminophenyl) disulphide have been prepared from the direct reaction of Schiff base and metals in 1:2 molar ratio to give:
Sn(SC6H4N=CHC6H4OCH3-o)4, Sn(SC6H4N=C(CH3)2)4, Sn(SC6H4N=C(CH2CH3)2)4, Bi(SC6H4N=CHC6H4OCH3-o)3, Bi(SC6H4N=C(CH3)2)3, SC6H4N=C(CH2CH3)2)3, Se(SC6H4N=CHC6H4O CH3-o)4, Se(SC6H4N=C(CH3) 2)4 and Se(SC6H4N=C(CH2CH3)2)4.
The reaction of the above metals with a mixture of iodine and Schiff bases give in (1:1:3) molar ratio the compounds SnI(SC6H4N=CHC6H4OCH3-o)3, SnI(SC6H4N=C(CH3)2)3, SnI(SC6H4N=C(CH2CH3)2)3, BiI(SC6H4N=CH-C6H4OCH3-o)2, BiI(SC6H4N=C(CH3)2)2, BiI(SC6H4N=C(CH2CH3)2)2, SeI(SC6H4N=CHC6H4 OCH3-o)3, SeI(SC6H4N=C(CH3)2)3 and SeI(SC6H4N=C(CH2CH3 )2)3. The compounds were characterized by microanalysis, infrared, UV/Visible spectroscopy and conductivity measurement.

ABSTRACT
The present work deals with the influence of aging conditions on thermal stability of authentic epoxy resin exposed to different aqueous media. Thermogravimetric analysis (TGA) shows that epoxy samples cured at moderate temperatures are more stable in acidic media than the samples cured at higher temperatures. The complete decomposition temperature of the epoxy resin exceeds 4000C for samples cured at 250C then decreased gradually for samples cured at 32 and 480C respectively.

Synthesis of the tetracyclic quinone compound (10) is described. The synthetic route adopted involves: preparation of the precursor 2-(2’-methoxy carbonyl benzoyl) – 1,4-benzoquinone (7), Diels-Alder reaction of the later with cyclopentadiene, [1,5]-aroyl migration in the resulting adduct (8), and finally ring closure in (9).

A number of zinc(II) and cadmium(II) complexes with two Schiff base ligands have been prepared. The ligands derived from the condensation of furfuraldehyde with butylamine (FBA) and hexylamine (FHA). The complexes which have the molar ratio of 1:2 (metal to ligand) had general formula [M(L)2]X2 (where M = Zn(II) or Cd(II) ; while X = Cl, NO3 or ½ SO ). The complexes were characterised by molar conductance measurements and the study of their infrared and ultraviolet absorption spectra, while zinc and cadmium contents were determined by standard procedures. These studies revealed the action of both ligands as neutral bidentate chelating ligands, formed complexes with tetrahedral structure

Selenium metal react with (RNHC(S)S)2 when (R = Ph or o-EtPh) in refluxing toluene to give the compounds [Se{RNHC(S)S}4] in high yields. The new trinuclear complexes were prepared by the reaction of [Se{RNHC(S)S}4] with some transition metal chloride salts in (1:2) molar ratio giving complexes of the general formula [M2Se{RNHC(S)S}4Cl4] where M = Co(II) and Ni(II). Adducts of these complexes with triphenyl phosphine and 1,10-phenanthroline were also prepared.
The new complexes and adducts were characterized by atomic absorption, infrared, UV-visible spectroscopy, conductivity and magnetic measurements.

An unexpected bis-anthranol (11) was obtained in an attempt to synthesis 1,4-dimethxy anthrone (5a) as a precursor in the total synthesis of tetracyclic anthrone systems (7 and 8) related to anthracyclinones. Oxidative-demethylation of (11) to the corresponding quinone (12) gave the unexpected quinone methide (13). The structure of the latter and the other compounds were confined by spectroscopic measurements.

The electrical conductivity of some symmetrical (1:1) alkali nitrates in different percentages of propanol-water mixtures at 298K have been measured.
The results were analysed using Lee-Wheaton (LW) equation, that is based on a method of which involving definite sizes for the ions. The electrical conductivities of NaNO3, KNO3 and CsNO3 in propanol-water mixtures, were measured. The values of conductivity parameters, (Λo, Ka, and R) at the best fit values of the standard deviation σs(Λ) have been calculated

The applicability of (LW) Lee-Wheaton equation is tested for three mixtures I-[Ni(phen)3]Cl2 + KBr, II-[Co(phen)3]Cl2 + KBr at 298.16K and III-[Co(phen)3]Cl2 + KBr at 308.16K. From the association constant KA and the ionic mobility λ° data for appropriate single electrolytes, detail information about the conductivity parameters are interpreted which have been affected by varying the temperature. A very good agreement is obtained between the experimental and calculated data. It is also found that (LW) equation is applicable to the salts and complexes, at different temperatures under studying.

Three compounds (A, B and C) were isolated by gel filtration chromatography of the precipitate produced by acetone precipitation of the aqueous extract of Myrtus communis L. fruits. Comparative molecular weights determination by gel filtration using standard proteins gave a value of 74990, 6310 and 620 dalton respectively. A single intraperitoneal injection of the isolated compounds (A, B and C) at a does of 77.5 mg/Kg was given to normal mice and some biochemical parameters were determined. The results of injection showed a significant decrease of serum glucose, cholesterol, triglycerides, total lipids level and glycogen content in liver tissues for both component A and B at different variation as compared to control group. However, compound C showed only a significant decrease in glycogen content in liver tissues.

Radiolysis of alanine and phenylalanine in aqueous solutions containing NADH has been carried out at different gas saturation and pH. It has been found that the oxidation of NADH decreases by increasing pH. Also, it has been observed that the yield of NADH oxidation in N2-saturated aqueous solutions is higher than that observed in oxygenated irradiated solution. It is concluded that more oxidizing radicals are generated through the deamination process as a result of the electron addition on the ammo acid. The results also have shown that the yield of NADH oxidation is higher slightly in the case of alanine as compared to that in the case of phenylalanine.

A house-built multi-electrodes detector has been designed for flow-injection electrochemical analysis. The detection system constructed intwo part, the auxiliary electrode (1 mm diameter Pt wire), the working electrodes (5 mm diameter glassy carbon (GC)), 5 mm diameter graphite (GR) and 5 mm diameter poly pyrrole plated (PPPE) as conducting polymer) placed in one part where as the reference electrode (Ag/AgCl,sat. KC1) placed in the second part. These electrodes were fitted into a teflon body cell, as it is a good isolator and easy to machine. One can readily change the working electrodes from GC, GR or PPPE without taking the cell apart. The cell based on a conventional laminar flow or on a wall-jet mode of operation. Use of the cell is illustrated by determination of Cu1+/Cu2+ couple on the different working electrodes. The best results obtained using the conducting polymer with lowest detection limit 10-7 M (6.3 ppb as Cu+2 ion).

A new method for the determination of Hemoglobin quantity in human blood serum based on Flow Injection Analysis ( FIA) was described . This method is relay on the decrease in the reduction peak of Potassium Ferricyanide K3[Fe(CN)6] which appeared at (-0.5V) vs. (Ag/AgCl, Sat. KCl) using Phosphate buffer (pH= 7.0) as a supporting and carrier solution. The method is sensitive and rapid. The procedure was successfully applied to the determination of Hemoglobin in various blood samples represent normal and different diseased cases such as: anemia, polysythemia. A comparison between the proposed method ( FIA) and colorimetric method was carried out using (36 samples), the relation was linear with a correlation coefficient (r= 0.9998).