ORIGINAL_ARTICLE
Spectroscopic and Conductometric Studies of Hexamethylenediamine Schiff Base Cu (II) Complexes
NEW Schiff base, o-HOC6H4CH:N(CH2)6N:CHC6H4OH-o, and its copper complexes have been characterized by using elemental analysis, UV-VIS, IR, 1H NMR, mass spectra, TGA, magnetic measurements and A.C electric conductivity. The formula of complexes were found (ML.nH2O.X) for 1:1 M:L where X=Cl-, Br-, NO3-, Ac-, L = Ligand. The ligand and its complexes have been characterized by IR ,UV-VIS, 1H NMR spectra and mass spectra which indicate that methine group and hydroxylic group in ortho position are involved in chelates besides to anions Cl-, Br-, NO3- and Ac-. Tetrahedral, octahedral and square planar geometries are proposed for the chelates based on their electronic spectra and magnetic moments. The investigated compounds behaved as semi- conducting materials.
https://ejchem.journals.ekb.eg/article_1253_7ed13da1b79d333a57194576bed83303.pdf
2010-10-31
613
629
10.21608/ejchem.2010.1253
ORIGINAL_ARTICLE
A Sensitive Kinetic Spectrophotometric Determination of Cefprozil and Dropropizine in Bulk and in Dosage Forms
ASIMPLE, accurate and sensitive kinetic spectrophotometric method is …. described for analysis of cefprozil and dropropizine. The method is based on kinetic investigations of the oxidation reaction of the drugs with alkaline potassium permanganate (KMnO4) at room temperature. The reaction is monitored spectrophotometrically by measuring the rate of change of absorbance of the resulting manganate species at 610 or 608 nm for cefprozil or dropropizine, respectively, with time. The two calibration curves at fixed-time method for the two drugs are utilized for the assay of drugs in the concentration ranges of 1.0-8.0 and 0.2-2.0 g ml-1 for cefprozil and dropropizine, respectively. The results are optimized and validated statistically and through recovery studies. The method has been successfully applied to the determination of cefprozil and dropropizine in pharmaceutical preparations. The results obtained are compared statistically with those given by the reference method. A proposal of the oxidation reaction pathway is postulated.
https://ejchem.journals.ekb.eg/article_1254_06e18434a1c889394e2eb68a3e5a0f1c.pdf
2010-10-31
631
643
10.21608/ejchem.2010.1254
Cefprozil
Dropropizine
potassium permanganate
Kinetic spectrophotometry and Pharmaceutical analysis
ORIGINAL_ARTICLE
Synthesis , Reactions and Antimicrobial Activity on Some Novel Phthalazinone Derivatives
ASIMPLE and efficient synthesis of [4-(3, 4-dimethylphenyl)-5, 6, 7, 8-tetrabromo-1-oxo-1H-phthalazin-2-yl]-acetic acid hydrazide (IV) has been carried out. The obtained hydrazide (IV) has been used in synthesis of some interesting heterocycles such as pyrazolone, thiazolidinone, pyrimidine, benzoxazine lactam, rhodanine, quinazoline and benzoxazinone (VIII
–XVII). Some of the prepared compounds tested for in vitro antibacterial activities. Among those tested, many compounds showed good antibacterial activities.
https://ejchem.journals.ekb.eg/article_1255_b1b47aad13ba9c94f5a0f3369774a9df.pdf
2010-10-31
645
660
10.21608/ejchem.2010.1255
Phthalazinone
pyrazolone
thiazolidinone
Azitidinone
Quinazoline
Pyrimidine derivatives and Antimicrobial activity
ORIGINAL_ARTICLE
The Quality of Chlorpyrifos Emulsifiable Concentrate Formulations
ASTUDY was conducted to investigate the degradation of ………chlorpyrifos, as well as studying the formation of its impurity sulfotep after storage at 54 2 oC for 1, 3, 7, 14, 21 days, at 72 2 oC for 1-5 days, and at room temperature within range 1-12 weeks of three commercial chlorpyrifos Emulsifiable Concentrate (EC) formulations (48% w/v) from the Egyptian market (manufactured from three different companies). The obtained results showed that chlorpyrifos was more stable after storage at 54 2 oC and at room temperature, whereas the rate of degradation increased after storage at 72 2 oC. There is no difference on the rate of degradation for all chlorpyrifos formulations under investigation. The sulfotep content of the three commercial formulations didn't show any correlation with storage temperature and storage time. However, in one of the commercial formulations of chlorpyrifos, the sulfotep content was more than the maximum permissible concentration of impurity recommended by FAO Specifications for chlorpyrifos (2008).
https://ejchem.journals.ekb.eg/article_1256_680674340ccbe0c36053467677f219b2.pdf
2010-10-31
661
671
10.21608/ejchem.2010.1256
chlorpyrifos
Degradation and Sulfotep
ORIGINAL_ARTICLE
The Behavior of 2-Chloroquinoline-3-carboxaldehyde towards Certain Primary Amines and Activated Methylenes
THE REACTIVITY of 2-chloroquinoline-3-carboxaldehyde (1b). ........towards primary amines (2a-d, 3, 4), hydrazines (5a-d, 6) and active methylene compounds (7,8) has been investigated. Assignments of the appropriate structures to the new reaction products have been assisted by compatible analytical and spectroscopic measurements.
https://ejchem.journals.ekb.eg/article_1257_1db5ab77c276ac6d94379bef55b8c4ad.pdf
2010-10-31
673
691
10.21608/ejchem.2010.1257
2-Chloroquinoline-3-carboxaldyde
Primary amines
Hydrazines
Activated methylenes
Reactions and Structural Elucidations
ORIGINAL_ARTICLE
Further Insight into the Reactivity of 3-(p- Chlorophenylimino-methyl) Chromone toward Phosphorus Reagents
ASERIES of phosphono-substituted and 5-membered ring ........chromenes were prepared in reasonable yields from the reactions of 3-(p-chlorophenyl-iminomethyl) chromone (1) with diffrent types of the Wittig-Horner reagents 4a-c, 9 in the presence of a base. On the other hand by applying cyanomethylenetriphenylphosphonium chloride 12 and allyltriphenylphosphonium bromide 15 to 1, the corresponding propanenitrile and methylpropenyl chromene derivatives were obtained.
https://ejchem.journals.ekb.eg/article_1258_793dcbd5e7a85f83de0f955a6a9cf511.pdf
2010-10-31
693
704
10.21608/ejchem.2010.1258
3-(Aryliminomethyl) chromone
Wittig-Horner reagents
Phosphonium salts
Phosphono and Substituted chromenes
ORIGINAL_ARTICLE
Phytochemical and Antimicrobial Studies on Acacia saligna Leaves
THE THERAPY of the medicinal plants has always been a part of our environment as they have several therapeutic virtues. These properties are generally attributed to secondary metabolites such as polyphenols. In this study we investigated the three extracts; ethyl acetate, methanolic and water extract of the leaves of Acacia saligna (Wendl H. L.) which is used traditionally in the treatment of various diseases. They were assayed against Gram-positive bacteria (Staphylococcus aureus, Staphylococcus pyogens, Bacillus cereus, Bacillus subtilis), Gram-negative bacteria (Escherichia coli), fungi and yeast (Candida albicans) using the diffusion and serial methods. The susceptibility of the microorganisms to the extracts of these plants was compared with each other and with selected antibiotics whereby the ethyl acetate extract being the most effective. The active ethyl acetate extract was phytochemicaly studied as well for their polyphenolic constituents, where they afforded sixteen polyphenolic compounds among which two different phenolic acids, two catechins and seven flavonoids were isolated for the first time from A. saligna. The structure of all the isolated compounds was elucidated on the basis of spectral analysis.
https://ejchem.journals.ekb.eg/article_1259_10802ffe808860cc72b7c4a0dd5606ea.pdf
2010-10-31
705
717
10.21608/ejchem.2010.1259
Acacia saligna leaves
Fabaceae
Phenolic compounds and Antimicrobial assay
ORIGINAL_ARTICLE
Synthesis and Characterization of Novel Cu(II) and Co(II) Azo Dye Complexes and Their Application on Nylon 6 and Wool
TWO models of azo disprse dye complexes were prepared by the reaction of 3-hydroxy- 4- ((2-hydroxyphenyl) diazenyl)-2-naphthoic acid (H 2L) with a divalent Cu(II) and Co(II) ions. The structures were confirmed by elemental analysis, spectral studies (1H NMR, IR, UV–visible, ESR), and magnetic measurements. IR spectra of the isolated complexes suggest that the H2L acts as a tetradentate ligand. The electronic spectra of the complexes and their magnetic moments suggest octahedral geometry. These dyes were applied to nylon 6 and wool fabrics. The results assessed for dyeing indicate an improving in washing and slightly enhanced in rubbing fastness rather than Fe (III) and Cr (III) complexes on wool fabrics , But approximately the same on nylon 6 fabrics.
https://ejchem.journals.ekb.eg/article_1260_8c766902bc275a7e699dbfefda90a5ab.pdf
2010-10-31
719
730
10.21608/ejchem.2010.1260
copper
Cobalt
complexes
Nylon 6
Wool and Washing
ORIGINAL_ARTICLE
Synthesis of New Pyrazolones and Fused Pyrazole Derivatives as Antimicrobial Agents
SOME new pyrazolone and fused pyrazole derivatives start ……from enaminone-type precursor. This approach constitutes a novel and advantageous alternative for the synthesis of the target heterocycles. Thus, the reaction of pyrazolone 1 and DMFDMA afforded 4-(dimeth-ylamino)methylidenepyrazol-3-one (2). Enaminone 2 was utilized as a key intermediate for the synthesis of new pyrazolones 8, 9, 12, and 14, fused pyrazolones 4-7, and 10 and the spiro adducts 15a, b. The antimicrobial activity of some of the newly synthesized adducts were evaluated against six strains of Gram positive, Gram negative and fungi in comparison with Ampicillin and Nystatine.
https://ejchem.journals.ekb.eg/article_1261_3580a94ae9d51cc59e7b3028efea7ab5.pdf
2010-10-31
731
744
10.21608/ejchem.2010.1261
Pyrazolones
Pyrazoloisoxazole
Pyrazolopyrazole
Pyrazoloquinoline
Pyrazoloenaminone
antimicrobial activity
ORIGINAL_ARTICLE
Preparation and Reactions of Optically Active Cyanohydrins Derived from 4- Chlorobenzaldehyde, Cyclohexanone and 2- Methylcyclohexanone using the (R) Hydroxynitrile lyase from Prunus amygdalus
CYANURATION of 4-chlorobenzaldehyde (1), cyclohexanone (2a) and 2-methylcyclo- hexanone (2b) yielded the racemic 2-hydroxy-2-(4-chlorophenyl)ethanenitrile (R,S)-3, cyclohexanone cyanohydrin 21a and (R,S)-2-methylcyclohexanone cyanohydrin (R,S)-21b. The same reaction can be completed by using acetone cyanohydrin (4) as a transcyanating agent. The optically active cyanohydrins (R)-3 and (R)-21b could be respectively obtained by hydrocyanation of 1 and 2b using (R)-hydroxynitrile lyase (R) PaHNL [EC 4.1.2.10] from almonds (Prunus amygdalus) as a chiral catalyst. Cyanohydrins 3 and 21 in their racemic and optically active forms undergo a number of transformations which involve either the hydroxyl group or the cyanide function. Moreover, derivatization of 3 and 21b with (S)-Naproxen chloride (S)-7 gave the respective diastereoisomers 8 and 22b. The optical activities of (R)-3 and 21b as well as their derivatives were recorded. The postulated structures of the new products were supported with compatible elementary and spectroscopic (IR, 1H NMR, 13C NMR, MS and X-ray crystallography) analyses. The antitumor activity of some selected racemic new products and their respective optically active analogues were undertaken. The structure-activity relationship (SAR) was also discussed.
https://ejchem.journals.ekb.eg/article_1262_6408b1e050e1980f823b673593ca4fa7.pdf
2010-10-31
745
775
10.21608/ejchem.2010.1262
antitumor activity
Carbonyl compounds
Cyanohydrins
Enzymes and Stereochemistry