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Humayun Pervez

Other affiliations: Quaid-i-Azam University
Bio: Humayun Pervez is an academic researcher from Bahauddin Zakariya University. The author has contributed to research in topics: Isatin & Ring (chemistry). The author has an hindex of 18, co-authored 45 publications receiving 981 citations. Previous affiliations of Humayun Pervez include Quaid-i-Azam University.

Papers
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Journal ArticleDOI
TL;DR: A series of isatins incorporating thiazoles, thiadiazole, benzothiazole and p-toluene sulfonyl hydrazide moieties have shown good affinity as antibacterial and/or antifungal agents which increased in most of the cases on complexation with the metal ions.
Abstract: A series of isatins incorporating thiazole, thiadiazole, benzothiazole and p-toluene sulfonyl hydrazide moieties, along with their cobalt(II), copper(II), nickel(II) and zinc(II) metal complexes have been synthesized and characterized by elemental analyses, molar conductances, magnetic moments, IR, NMR and electronic spectral data. These compounds have been screened for antibacterial activity against Escherichia coli, Bacillus subtillis, Shigella flexneri, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi, and for antifungal activity against Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glaberata using the agar-well diffusion method. All the synthesized compounds have shown good affinity as antibacterial and/or antifungal agents which increased in most of the cases on complexation with the metal ions.

230 citations

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TL;DR: The antibacterial potency of the Schiff bases increased upon chelation/complexation in comparison to the uncomplexed Schiff bases against the tested bacterial species thus, opening new approaches to find new ways in the fight against antibiotic-resistant strains.
Abstract: 2-Amino-1,3,4-thiadiazole undergoes a condensation reaction with furane-, thiophene- and pyrrole-2-carboxaldehyde to form tridentate NNO, NNS and NNN donor Schiff bases. These Schiff bases were further used to obtain complexes of the type [M(L)2]X, where M = Co(II), Cu(II), Ni(II) or Zn(II), L = L1, L2 or L3 and X = Cl2. The new compounds described here have been characterized by their physical, spectral and analytical data, and have been screened for antibacterial activity against several bacterial strains such as Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. The antibacterial potency of the Schiff bases increased upon chelation/complexation in comparison to the uncomplexed Schiff bases against the tested bacterial species thus, opening new approaches to find new ways in the fight against antibiotic-resistant strains.

76 citations

Journal ArticleDOI
TL;DR: This study presents the first example of inhibition of urease by isatin-thiosemicarbazones and provides a solid basis for further research on such compounds to develop more potent inhibitors.
Abstract: A series of 15 previously reported N(4)-substituted isatin-3-thiosemicarbazones 3a-o has been screened for cytotoxic, antibacterial, antifungal and urease inhibitory activities. Compounds 3b, 3e and 3n proved to be active in cytotoxicity assay; 3e exhibited a high degree of cytotoxic activity (LD(50) = 1.10 x 10(-5) M). Compound 3h exhibited significant antibacterial activity against B. subtilis, whereas compounds 3a, 3k and 3l displayed significant antifungal activity against one or more fungal strains i.e. T. longifusus, A. flavus and M. canis. In human urease enzyme inhibition assay, compounds 3g, 3k and 3m proved to be the most potent inhibitors, exhibiting relatively pronounced inhibition of the enzyme. These compounds, being non-toxic, could be potential candidates for orally effective therapeutic agents to treat certain clinical conditions induced by bacterial ureases like H. pylori urease. This study presents the first example of inhibition of urease by isatin-thiosemicarbazones and as such provides a solid basis for further research on such compounds to develop more potent inhibitors.

68 citations

Journal ArticleDOI
TL;DR: All the compounds showed good antib bacterial and antifungal activity which increased on coordination with the metal ions thus, introducing a novel class of organometallic-based antibacterial and antIFungal agents.
Abstract: Organometallic-based, 1,1'-diacetylferrocene-derived antibacterial and antifungal thiocarbohydrazone, carbohydrazone, thiosemicarbazone and semicarbazone have been prepared by condensing equimolar amount of 1,1'-diacetylferrocene with thiocarbohydrazide, carbohydrazide thiosemicarbazide and semicarbazide, respectively. These were used as ligands for the preparation of their cobalt (II), copper (II), nickel (II) and zinc (II) metal complexes. All the synthesized ligands and their complexes were characterized by IR, NMR, elemental analyses, molar conductances, magnetic moments and electronic spectral data. These synthesized compounds were screened for their antibacterial activity against Escherichia coli, Bacillus subtillis, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi, and for antifungal activity against Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glaberata using the agar-well diffusion method. All the compounds showed good antibacterial and antifungal activity which increased on coordination with the metal ions thus, introducing a novel class of organometallic-based antibacterial and antifungal agents.

66 citations

Journal ArticleDOI
TL;DR: A new series of 12 N4-substituted isatin-3-thiosemicarbazones 2a-l has been synthesized, characterized and screened for in vitro cytotoxic, phytotoxic and urease inhibitory effects, indicating their usefulness as inhibitors of soil ureases.
Abstract: A new series of 12 N4-substituted isatin-3-thiosemicarbazones 2a-l has been synthesized, characterized and screened for in vitro cytotoxic, phytotoxic and urease inhibitory effects. All the compounds proved to be active in the brine shrimp bioassay; 2a, 2b, 2d, 2f and 2h-l exhibited a high degree of cytotoxic activity (LD50 = 1.10 × 10− 5 M–3.10 × 10− 5 M). In urease-inhibition assay, compounds 2a, 2b, 2e, 2f, 2h-j and 2l proved to be potent inhibitors displaying relatively much greater inhibition of the enzyme with IC50 values ranging from 20.6 μM to 50.6 μM. Amongst these, 2a and 2f were found to be the most potent ones exhibiting pronounced inhibition with IC50 value 20.6 μM. All the synthetic compounds showed weak to moderate (10–40%) phytotoxicity at the highest tested concentration (500 μg/mL) indicating their usefulness as inhibitors of soil ureases.

52 citations


Cited by
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Journal ArticleDOI
10 Mar 1970

8,159 citations

Journal Article
TL;DR: In this paper, uses of Schif f bases and their metalcomplexes as catalysts, in various biological systems, polymers and dyes, besides some uses as antifertilityand enzymatic agents.
Abstract: , which are condensation products ofprimary amines and aldehydes or ketones (RCH=NR ′,where R & R ′ represents alkyl and / or aryl substituents).This paper reviews uses of Schif f bases and their metalcomplexes as catalysts, in various biological systems,polymers and dyes, besides some uses as antifertilityand enzymatic agents.

325 citations

Journal ArticleDOI
TL;DR: A series of isatins incorporating thiazoles, thiadiazole, benzothiazole and p-toluene sulfonyl hydrazide moieties have shown good affinity as antibacterial and/or antifungal agents which increased in most of the cases on complexation with the metal ions.
Abstract: A series of isatins incorporating thiazole, thiadiazole, benzothiazole and p-toluene sulfonyl hydrazide moieties, along with their cobalt(II), copper(II), nickel(II) and zinc(II) metal complexes have been synthesized and characterized by elemental analyses, molar conductances, magnetic moments, IR, NMR and electronic spectral data. These compounds have been screened for antibacterial activity against Escherichia coli, Bacillus subtillis, Shigella flexneri, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi, and for antifungal activity against Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glaberata using the agar-well diffusion method. All the synthesized compounds have shown good affinity as antibacterial and/or antifungal agents which increased in most of the cases on complexation with the metal ions.

230 citations

Journal ArticleDOI
TL;DR: A macrocyclic hydrazone Schiff base was synthesized by reacting 1,4-dicarbonyl phenyl dihydrazide with 2,6-diformyl-4-methyl phenol and a series of metal complexes with this new Schiff base were synthesised by reaction with Co(II), Ni(II) and Cu(II).

220 citations