Iraqi National Journal Of Chemistry

The paper deals with kinetic data of Beckmann rearrangement of substituted anti
benzaldoxime to substituted benzoic acid and ammonia by action of perchloric acid in
10% ethanol by volume . A spectrophotometric method was used for this
investigation , by following the decay absorbances of benzaldoximes at the proper
analytical wavelengths . The reaction was found to obey a pseudo first order kinetic
with respect to oxime . The observed rate constants k were evaluated in the
temperature in the range 323-353 K and found to depend on temperature and donor or
acceptor property of the substituent as well as its position on the aromatic rings .
Finally the activation parameters for Beckmann rearrangement reactions were
calculated and discussed .

The
Potentials with iodimetric reaction of sulphur reducing agents using
sulphide and Cyanide ion_Selective electrodes were all negative resulting from
ion_exchange of produced iodide ions on the membrane surfaces of the electrodes
.The calculated free energy changes values were positive with negative entropy
change values which are an inverse to corresponding values obtained with Platinum
electrode .∆H values were mostly low and positive while equilibrium constants were
extremely low as it seems to be no occurrence of iodimetric reactions that have been
trustly confirmed by platinum electrode . This discrepancy was attributed to high
input impedance of ISEs membranes which prevent the flow of electrons across their
membranes, and the conductivity is ionic . Therefore , this research confirmed
experimentally that these ISEs are unresponsive to oxidation _ reduction potentials
and the results obtained might well be considered for other ISEs.

This research aims to attainment two essential purposes : first, using of inorganic
fire retardant which represent zinc borate to increase the flame retardancy for
advanced composite material consist of araldite resin (AY103) reinforced by hybrid
fibers from carbon and Kevlar fibers as a woven roving ) º 45 - º 0 ( , by using a surface
layer from zinc borate as a coating layer of (4mm) thickness .Then, this system was
exposed to a direct flame generated from Oxyacetylene torch (3000ºC) with different
flame exposure distances [10,15,20mm], and study the range of resistance of
retardant material layer to the flames and protected the substrate . Second, forming a
hybrid fire retardant by added antimony trioxide with various amount
(10%,20%,30%) to zinc borate for enhance the action of this material to react flame
and exposure this hybrid material to same flame temperature and exposure distances.
Method of measuring the surface temperature opposite to the flame was used to
determined the heat transferred to composite material . the best results was obtained
with large exposed distance and large percentage from protective layer which is zinc
borate with (30%) antimony trioxide .

A series of new Schiff base and 1,3-Oxazepine compounds have been
synthesized. 4-Aminophenazone was condensed with various aromatic aldehydes in
ethanol in the presence of glacial acetic acid as catalyst to yield the Schiff base [2-4].
These Schiff bases were reacted with maleic anhydride and phthalic anhydride in dry
benzene to give a seven-membered heterocyclic ring derivatives [5-7] and [8-10],
respectively.
The prepared compounds were identified by their uncorrected melting points,
elemental analysis and FT-IR spectra.

A new application of an indirect atomic absorption spectrometric (AAS)
method was offered for the assay of low concentrations of cefotaxime (CFX) in
pharmaceutical in pure and pharmaceutical dosage form with good accuracy and
precision. The method is depended on the formation of chelating complex between the
drug cefotaxime and rhodium(II) to form orange-yellowish product. All experimental
parameters such as, pH, concentration of rhodium, reaction time, extraction time and
phase ratio have been investigated. The linearity (2-50) µg mL-1, detection limit (S/N)
of 0.13 µg mL-1, accuracy as the %Erel of 1.59, and recoveries ranged from 101.2
101.87%, with mean value of 101.59±0.73. The proposed method was applied for the
determination of CFX in the drug Sefotak by both direct calibration and standard
additions procedures and found to be 989.87 and 970.93 mg per unite, respectively
compared with the stated value of 1000 mg per unite. This method is also compared
statistically with direct determination by using UV-VIS spectrophotometric technique
which is preformed in our laboratory and found to be insignificant at 95% confidence
level. All statistical calculations were implemented via the chemsoftware Minitab
version 11.

A tridentate ligand (FAC), 2-(caproic-6-yliminomethyl) furan, derived from 2
furaldehyde and 6-aminocaproic acid and its cobalt(II), nickel(II) and copper(II)
complexes have been synthesized by the template condensation of the 2-furaldehyde
with 6-aminocaproic acid in the presence of cobalt(II), nickel(II) or copper(II)
salts in molar ratio of M:L (1:2) which forms the metal complexes of type [M(L)2]
(where M = Co(II), Ni(II) or Cu(II)), and of M:L (1:1) of type [M(L)(H2O)3]Cl (where
M = Co(II), Ni(II) or Cu(II)). The prepared complexes were characterized by metal
content analyses, IR, electronic spectroscopy, magnetic susceptibility and
conductivity measurements. IR spectra confirm coordination of imine nitrogen, the
negative oxygen atom of the carboxyl group and oxygen of the furan ring to the
central metal ion. The magnetic moment data suggested for all complexes to have an
octahedral geometry around the central metal ion. The electronic spectral data also
agree with their proposed structures.

Human serum AChE activity is measured in vitro using modified
Ellman method and shows a wide range between (4.925-8.755)
µmole/3min/ml. The activity in men was higher than in women. The
possible medical importance of Vitamin B12 as a remover of the effects of
poisonous and inhibiting compounds of AChE as possible substitute of
Atropine was tested, the results showed that Vitamin B12 behaved as a
reactivator, and the values of reactivation of both of Vitamin B12 and
Atropine on the activity of'inhibited AChE by heterocyclic compounds
sometimes appear approximately equal, these results lead to the
conclusion that, it is possible to use Vitamin B12 instead of Atropine in
treatment of poisoning caused by these types of inhibitors. Mechanism
of action of Vitamin B12 as reactivator was proposed.

Modification of gas chromatographic technique for separation
methylethoxysilane compounds which were synthesized by the reaction the absolute
ethanol with methylchlorosilane compounds. The addition of dry absolute ethanol to
methylchlorosilane compounds in the presence of a dry stream of nitrogen gas to
eliminate the liberated HCl gas. This method was found to be the suitable method for
preparation methylethoxysilane compounds. The optimum parameter selected after
careful and precise studies were between 20 – 30 ml \ min to carriers gas flow rate,
while applied temperature of detector and injection part are 250 °C and 225 °C
respectively. The results showed that suitable chromatographic column for the
separation of methylchlorosilane compounds is 50% [5% dioctyl phthalate ] + 50%
[10% OV- 101 ] .While 10 % OV – 101 column was found to be the best for the
separation of methylethoxysilane compounds . Accordingly , a linear relationship for
the calibration curve between concentration and peak area was achieved for
methylchlorosilane and methyl ethoxysilane with correlation coefficients were ranged
between 0.9991- 1. The results of percentage RSD for the methylchlorosilane and
methylethoxysila were 0.51-2.08 and 0.053-1.37 respectively.

Mixed ligand complexes of the type [(M)2LL′(OH)2(H2O)4] (where M = Co(II),
Ni(II), Cu(II) or Zn(II) ; L = biacetyl ; while L′ = deprotonated ethylene glycol) have
been synthesized by 2:1:1 molar reactions of metal salts with biacetyl and ethylene
glycol. Also [(M)2L1L2(OH)4(H2O)2] complexes (where M = Co(II), Ni(II), Cu(II) or
Zn(II) ; L1 = biacetyl ; while L2 = ethylenediamine) have been synthesized by 2:1:1
molar reactions of metal salts with biacetyl and ethylenediamine. The resulting
complexes have been characterized by the metal content measurements, molar
conductance measurements, infrared, electronic spectra and magnetic moment
measurements. The complexes are non-electrolytes as is evident from low values of
their molar conductance. The infrared spectral studies of the complexes indicate that
the ligands behave as bidentate chelating ligands. Also the IR studies show that the
water molecules are coordinated in all the complexes and the metal centres are
bridged by (OH) groups. Also (OH) group is coordinated to each metal ion in the
[(M)2L1L2(OH)4(H2O)2]. The different studies reveal dinuclear nature of all the
complexes and the two metal atoms are hexacoordianted with octahedral geometry

This study is concerned with the synthesis and characterization of the
3–phenylthio/3-phenoxyazetidine-2-one 3(a-e). These compounds were prepared by
phenylthio/phenoxyacetic acid (1) with the appropriate Schiff bases 2(a-d) in the
presence of triethylamine with phosphorusoxychloride in dry methylene chloride under
nitrogen atmosphere at 0˚C. The active acid chloride reacts with triethylamine to
generate corresponding ketene in situ which further reacts with Schiff’s base to furnish
corresponding 3–phenylthio/3-phenoxyazetidine-2-one 3(a-e) in moderate yields .

The polarographic behaviour of ambilhur (niridazole) [1-(5-Nitro-2-thiazolyl)
2-imidazolidinone(I)] have been studied. The drug give a well sensitive defined single
peak at about -0.45V in carbonate buffer solution at pH 7.4 and -0.46V in serum
carbonate buffer and at -0.34V in urine-carbonate buffer.
The lowest determined concentration in aqueous carbonate buffer 9.1×10-7 M ,
in serum-carbonate buffer media was 5.4×10-7 M and 3.2×10-7 M in urine-carbonate
media with correlation coefficient 0.998, 0.996, 0.999. the relationship between
concentration and diffusion current Ip was linear for all solutions.

The
(Accepted for publication 28/2/2011)
aim of this study was to develop a procedure for prepared ,and
characterization a controlled-release microspheres polymers like chitosan , polyvinyl
alcohol (PVA) containing Diltiazem HCl (DTZ), as a model drug, was obtained using
a modified emulsification/solvent-evaporation method, induced by addition of
glutaraldehyde (GA) as a crosslinking agent. The microspheres were characterized by
Fourier transform infrared spectroscopy, differential scanning calorimetry (DSC), and
photomicrographs microscopy. The effect of different process parameters, such as
drug/polymer ratio and stirring rate during preparation of microspheres, on the
morphology, size distribution, and in vitro drug release of microspheres was studied.
As expected, stirring rate influenced particle size distribution of microspheres and
hence drug release profiles. By increasing the stirring speed from 400 to 1200 rpm,
the mean diameter of microspheres decreased from 350 µm to 104 µm. The drug
release rate from smaller microspheres was faster than from larger microspheres.
Increasing the drug content of microspheres from 20% to 40% w/w led to
significantly faster drug release from microspheres. It was also studied the release of
(DTZ) at different pH values (1.2, and 7.4) at 37°C. The results indicated that drug
release was much higher at pH 1.2 than that of at pH 7.4.

Hemoglobin A1c is the most parameters for the monitoring of metabolic control of
patients with diabetes mellitus. The aim of this study is to determine the reference range of
glycosylated hemoglobin (HbA1c%) in an Iraqi population (males and females) by using
immune method with agglutinations.
Blood samples were collected from 100 healthy subjects (50 females and 50 males),
age ranged between (20-75) years old. The reference value of HbA1c % was (5.34 ± 0.67) %
in females and (5.67 ± 0.73) % in males. The present study found a very high positive
significant difference between HbA1c % and BMI in both gender. A positive significant was
observed between HbA1c % with systolic and diastolic blood pressure in males, whereas
there is no significant differences between HbAIc % and blood pressure in females.