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Khalid Maher

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Papers by Khalid Maher

Research paper thumbnail of Optimization Extraction of Bougainvillea Glabra Violet Bracts Pigment

The Journal of The University of Duhok, Dec 18, 2019

Bougainvillea glabra violet bract flower was selected to explore natural pigment. Various solvent... more Bougainvillea glabra violet bract flower was selected to explore natural pigment. Various solvent combinations were used to extract the pigments from the flowers. UV-Vis spectroscopy were used to investigate the suitable solvent and the optimum portion ratio for pigment extraction by maceration. The results of mass of floral bract to (50%) ethanol solvent portion ratio in a constant volume (20 ml) was found to be (0.1 gm /20 ml), measured at λmax 548 nm and the maceration extraction time for pigment extraction from violet bracts was 72 h. Different neutral, basic and acidic organic solvent solutions (ethanol, methanol, 2-propanol, diethyl ether, ethyl acetate, 2-butanol, chloroform and acetone), shows different result of extraction for the pigments. The combination 1:1 methanol: water ratio was found to be a suitable combination solvent for pigment extraction and distilled water solvent give the best results to protect the pigment violet color for Bougainvillea g. bracts from conversion in the period for 15 days.

Research paper thumbnail of A Flexible Protocol for the Preparation of Quinoline Derivatives through Mitsunobu Reaction and Aza-Wittig Intermediate

Research paper thumbnail of ORIENTAL JOURNAL OF CHEMISTRY Crown Ether Schiff bases and their Complexes: Recent Advances (A Review )

Research paper thumbnail of Synthesis and Antimicrobial Activities of Some Novel 2,3-Substituted-1,3-Thiazolidin-4-ones Derived from 2-Amino-1,3-thiazole

Asian Journal of Chemistry, 2017

New 2,3-substituted-1,3-thiazolidin-4-one (6a-f) were prepared by cyclocondensation of 2-[6-(4-ch... more New 2,3-substituted-1,3-thiazolidin-4-one (6a-f) were prepared by cyclocondensation of 2-[6-(4-chlorobenzyloxy)-2-naphthyliden]-4-(4-substituted phenyl)-5-methyl-1,3-thiazole (5a-f) and mercaptoacetic acid in benzene. The synthesized compounds were characterized on the basis of elemental analysis, 1 H NMR, 13 C NMR and FT-IR. The prepared compounds have been screened in vitro against two Grampositive Staphylococcus aureus, Staphylococcus epidermidis, and two Gram-negative Escherichia coli, Pseudomonas aernuginosa for antibacterial activity and two fungal strains Candida albicans, Candida krusei for antifungal activity using ciprofloxacin, ampicillin and ketoconazole with minimal inhibitory concentration (MIC) value of 10 mcg/L in DMSO. Compounds 6a and 6d showed good antibacterial and antifungal activities compared to reference medications utilized within this study.

Research paper thumbnail of Schiff Bases Derived from 2-Hydroxynaphthalene-1-carbaldehyde and their Metal Complexes

Asian Journal of Chemistry

; AJC-18860 2-Hydroxynaphthalene-1-carbaldehyde is a key predecessor to an assortment coordinatin... more ; AJC-18860 2-Hydroxynaphthalene-1-carbaldehyde is a key predecessor to an assortment coordinating agent and the Schiff bases derived from these ligands played a unique role in the development of important biomolecules which exhibit a widely range as a model system for biological macromolecules. Schiff bases formed from o-hydroxy aromatic ketones and aldehydes are stellar design for the study of keto-enol tautomerism in liquid and solid state. The metal-Schiff base complexes obtained from 2-hydroxynaphthalene-1-carbaldehyde had been revealed to show a broad area of biological effectiveness, catalytic reaction, sensors, selective electrodes and fluorescent.

Research paper thumbnail of Crown Ether Schiff bases and their Complexes: Recent Advances (A Review )

Oriental Journal of Chemistry, Aug 11, 2018

In recent years, an interest in the synthesis of crown ether Schiff bases and their complexes has... more In recent years, an interest in the synthesis of crown ether Schiff bases and their complexes has been increased, due to the significance and broadly the uses of these compounds in various fields. The present review paper outline extensive recent advances literature survey on the crown ether including azomethine group and their complexes with the tough and easy granter atoms, has been reconsidered. Emphasis has been done on element complexation with crown ether holding Schiff bases to enable the researchers to procure valuable information of the chelating activity of crown ether containing azomethine group and their enforcement.

Research paper thumbnail of Optimization Extraction of Bougainvillea Glabra Violet Bracts Pigment

The Journal of The University of Duhok, Dec 18, 2019

Bougainvillea glabra violet bract flower was selected to explore natural pigment. Various solvent... more Bougainvillea glabra violet bract flower was selected to explore natural pigment. Various solvent combinations were used to extract the pigments from the flowers. UV-Vis spectroscopy were used to investigate the suitable solvent and the optimum portion ratio for pigment extraction by maceration. The results of mass of floral bract to (50%) ethanol solvent portion ratio in a constant volume (20 ml) was found to be (0.1 gm /20 ml), measured at λmax 548 nm and the maceration extraction time for pigment extraction from violet bracts was 72 h. Different neutral, basic and acidic organic solvent solutions (ethanol, methanol, 2-propanol, diethyl ether, ethyl acetate, 2-butanol, chloroform and acetone), shows different result of extraction for the pigments. The combination 1:1 methanol: water ratio was found to be a suitable combination solvent for pigment extraction and distilled water solvent give the best results to protect the pigment violet color for Bougainvillea g. bracts from conversion in the period for 15 days.

Research paper thumbnail of A Flexible Protocol for the Preparation of Quinoline Derivatives through Mitsunobu Reaction and Aza-Wittig Intermediate

Research paper thumbnail of ORIENTAL JOURNAL OF CHEMISTRY Crown Ether Schiff bases and their Complexes: Recent Advances (A Review )

Research paper thumbnail of Synthesis and Antimicrobial Activities of Some Novel 2,3-Substituted-1,3-Thiazolidin-4-ones Derived from 2-Amino-1,3-thiazole

Asian Journal of Chemistry, 2017

New 2,3-substituted-1,3-thiazolidin-4-one (6a-f) were prepared by cyclocondensation of 2-[6-(4-ch... more New 2,3-substituted-1,3-thiazolidin-4-one (6a-f) were prepared by cyclocondensation of 2-[6-(4-chlorobenzyloxy)-2-naphthyliden]-4-(4-substituted phenyl)-5-methyl-1,3-thiazole (5a-f) and mercaptoacetic acid in benzene. The synthesized compounds were characterized on the basis of elemental analysis, 1 H NMR, 13 C NMR and FT-IR. The prepared compounds have been screened in vitro against two Grampositive Staphylococcus aureus, Staphylococcus epidermidis, and two Gram-negative Escherichia coli, Pseudomonas aernuginosa for antibacterial activity and two fungal strains Candida albicans, Candida krusei for antifungal activity using ciprofloxacin, ampicillin and ketoconazole with minimal inhibitory concentration (MIC) value of 10 mcg/L in DMSO. Compounds 6a and 6d showed good antibacterial and antifungal activities compared to reference medications utilized within this study.

Research paper thumbnail of Schiff Bases Derived from 2-Hydroxynaphthalene-1-carbaldehyde and their Metal Complexes

Asian Journal of Chemistry

; AJC-18860 2-Hydroxynaphthalene-1-carbaldehyde is a key predecessor to an assortment coordinatin... more ; AJC-18860 2-Hydroxynaphthalene-1-carbaldehyde is a key predecessor to an assortment coordinating agent and the Schiff bases derived from these ligands played a unique role in the development of important biomolecules which exhibit a widely range as a model system for biological macromolecules. Schiff bases formed from o-hydroxy aromatic ketones and aldehydes are stellar design for the study of keto-enol tautomerism in liquid and solid state. The metal-Schiff base complexes obtained from 2-hydroxynaphthalene-1-carbaldehyde had been revealed to show a broad area of biological effectiveness, catalytic reaction, sensors, selective electrodes and fluorescent.

Research paper thumbnail of Crown Ether Schiff bases and their Complexes: Recent Advances (A Review )

Oriental Journal of Chemistry, Aug 11, 2018

In recent years, an interest in the synthesis of crown ether Schiff bases and their complexes has... more In recent years, an interest in the synthesis of crown ether Schiff bases and their complexes has been increased, due to the significance and broadly the uses of these compounds in various fields. The present review paper outline extensive recent advances literature survey on the crown ether including azomethine group and their complexes with the tough and easy granter atoms, has been reconsidered. Emphasis has been done on element complexation with crown ether holding Schiff bases to enable the researchers to procure valuable information of the chelating activity of crown ether containing azomethine group and their enforcement.

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