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Hasnah Osman

    Hasnah Osman

    ABSTRACT
    Abstract The reaction of benzyl o-vanillin 1 with ophenylenediamine 2PD, in dichloromethane at low conditions produced novel amino benzeneamine: 2-amino-N-(2-benzyloxy-3-methoxybenzylidene) benzeneamine 2. The intermediate 2 is isolated... more
    Abstract The reaction of benzyl o-vanillin 1 with ophenylenediamine 2PD, in dichloromethane at low conditions produced novel amino benzeneamine: 2-amino-N-(2-benzyloxy-3-methoxybenzylidene) benzeneamine 2. The intermediate 2 is isolated and ...
    A simple, reliable a 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxy-phenyl)-2-(4-sulfophenyl)-2H-tetrazolium, (MTS) assay was conducted to evaluate the potential cytotoxic effects of levodopa, a "gold standard therapy" for Parkinsonism,... more
    A simple, reliable a 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxy-phenyl)-2-(4-sulfophenyl)-2H-tetrazolium, (MTS) assay was conducted to evaluate the potential cytotoxic effects of levodopa, a "gold standard therapy" for Parkinsonism, and its complex with Hydroxypropyl-β-Cyclodextrin (HP-β-CD) on an astrocyte cell line. The cells were incubated in a range of concentrations from 4.69 to 300 μg/mL levodopa, HP-β-CD or the complex for up to 72 hours. At every 24-hour interval, the optical density (OD), which reflects the number of viable cells, was recorded. In general, linear dose-dependent cytotoxicity profiles were observed for the cells subjected to levodopa or the complex, whereas a slightly triphasic response was observed for the cells exposed to HP-β-CD. A significant difference (P < 0.05) in cytotoxicity was detected between the HP-β-CD-treated group and the levodopa-treated group. In particular, we observed that the cells treated with the complex, even at the highest concentrations (> 200 μg/mL), exhibited improved tolerability in a time-dependent manner, which may indicate the potential ability of HP-β-CD to mask the toxic effects of levodopa via complexation.
    A series of some new bisadducts possessing five, six membered and coumarin subunits were synthesized by the condensation of heterocyclic aldehydes with active methylene compounds and characterized by IR, NMR and X-ray crystallographic... more
    A series of some new bisadducts possessing five, six membered and coumarin subunits were synthesized by the condensation of heterocyclic aldehydes with active methylene compounds and characterized by IR, NMR and X-ray crystallographic studies and were assayed as antitubercular agents. Among the bisadducts, 4-hydroxy-3-[(4-hydroxy-2-oxo-2H-3-chromenyl)(3-thienyl)methyl]-2H-2-chromenone 3a was found to be the most promising compound, active against Mycobacterium tuberculosis (Mtb) H37Rv and isoniazid resistant Mycobacterium tuberculosis (INHR-Mtb) with minimum inhibitory concentration 5.22 and 8.34 microM, respectively.
    The present research work describes the synthesis of new series of nicotinonitrile (2) and furo[2,3-b]pyridine (3) heterocycles bearing thiophene substituent. The nicotinonitrile derivatives were prepared from the corresponding... more
    The present research work describes the synthesis of new series of nicotinonitrile (2) and furo[2,3-b]pyridine (3) heterocycles bearing thiophene substituent. The nicotinonitrile derivatives were prepared from the corresponding 3-cyano-(2H)-pyridones (1a–f) in excellent yields. The ring cyclization of the nicotinonitrile derivatives (2a–f) in the presence of sodium methoxide provided the furo[2,3-b]pyridines (3a–f) in moderate to good yields. All the newly synthesized compounds were characterized by extensive NMR analysis data, including 1D-NMR experiments (1H and 13C) and 2D-NMR experiments (COSY, HMBC, HSQC), as well as HRESIMS data. All the final products were subjected for cytotoxic activity against five different tumour cell lines including HeLa (cervical), DU145 (prostate), HepG2 (liver), MDA-MB-231 (breast-ER negative) and MCF7 (breast-ER positive), in addition to HSF1184 (normal human fibroblast) using the MTT assay. Compounds 2d and 3e were found to exhibit promising cytotoxicity with IC50 of &lt; 20 µM against all different tested tumour cell lines. In addition, these compounds showed high selectivity (40–287 folds) for tumour cells over normal cells.Graphical abstract
    A series of 6,7-dimethoxy-3-(4-pyridyl)-2,3,3a,4-tetrahydroindeno[1,2-c]pyrazol-2-yl-4-substituted phenylmethanone/ethanone derivatives were synthesized and in vitro activity against mycobacterium tuberculosis (MTB) and INHR-MTB were... more
    A series of 6,7-dimethoxy-3-(4-pyridyl)-2,3,3a,4-tetrahydroindeno[1,2-c]pyrazol-2-yl-4-substituted phenylmethanone/ethanone derivatives were synthesized and in vitro activity against mycobacterium tuberculosis (MTB) and INHR-MTB were carried out. Among the synthesized compounds, compound (4h) 6,7-dimethoxy-3-(4-pyridyl)-2,3,3a,4-tetrahydroindeno[1,2-c]pyrazol-2-yl-4-pyridyl methanone was found to be the most active agent against MTB and INHR-MTB with a minimum inhibitory concentration of 0.22 μM.
    The Fabaceae is recognized as the third largest and one of the most influential families among the flowering plants. Furthermore, its name is linked to “Legumes”, which represent a vast group of angiosperms in the continents utilized as... more
    The Fabaceae is recognized as the third largest and one of the most influential families among the flowering plants. Furthermore, its name is linked to “Legumes”, which represent a vast group of angiosperms in the continents utilized as crops, forages, and green manures. It is recognized for diverse constituents, covering both primary metabolites include lectins, chitinases, various proteases, and α-amylase inhibitors, as well as secondary metabolites include flavonoids, alkaloids, terpenoids, tannins, and phenolics. Fabaceae flavonoid plays an important role in the legumes’ adaptability to biological surroundings as defensive agents (phytoalexins) and as chemical signals in a symbiotic relationship with a bacterial species known as rhizobia. Considering their important role in plant defense and benefits to human healthiness, a number of studies on the Fabaceae plant have been performed, namely isolation and screening of the purified compounds and their biological activity. This study outlines specified issues on the chemical structure, biosynthesis, biological activities, and medicinal uses of Fabaceae compounds.
    Despite organophosphorus pesticides (OPPs) benefits in controlling vector-borne diseases and noxious insects, the bioaccumulation and persistence in the soil system may metamorphose into new substances which could pose a serious threat to... more
    Despite organophosphorus pesticides (OPPs) benefits in controlling vector-borne diseases and noxious insects, the bioaccumulation and persistence in the soil system may metamorphose into new substances which could pose a serious threat to the ecosystems and human health. The generally low levels of OPPs residues and often the complexity of the soil matrix are the issues that researcher must deal with. Thus, it is essential to isolate and preconcentrate the OPPs from the matrix to reduce interference effects to obtain a reliable detection. Researchers have reported sample preparation techniques as a promising approach to improve analytical measurement of merits including recovery, precision, linearity, limit of detection, and limit of quantification. Under the selected conditions, limits of detection range between 0.001 and 143 ng/mL, and extraction recovery range between 5 and 154% were obtained. This review evaluates the challenges and opportunities, emphasizes the prospects of sampling techniques and various (micro)extraction coupled with chromatographic methods in different soil samples. Based on the finding, the extraction efficiency depended largely on the interaction between OPPs and extraction media. The fate, migration, toxicity impact, sampling procedure, and storage which influenced the sample preparation were comprehensively discussed.
    Abstract Four heterocyclic embedded Schiff base derivatives (1–4) were synthesized and characterized by melting point, elemental analysis, FTIR, 1H, 13C NMR, UV–Visible spectral data. The structures of compounds 1, 2 and 4 were... more
    Abstract Four heterocyclic embedded Schiff base derivatives (1–4) were synthesized and characterized by melting point, elemental analysis, FTIR, 1H, 13C NMR, UV–Visible spectral data. The structures of compounds 1, 2 and 4 were successfully established through single crystal X-ray diffraction analysis. In vitro cholinesterase inhibition assays showed that the cyclized derivative 1 displayed higher BuChE enzyme inhibitory activity with IC50 value of 1.45 ± 0.09 μM. The anti-proliferative efficacies of the compounds were also evaluated using human colorectal HCT 116 and breast MCF-7 adenocarcinoma cell lines. In addition, a human normal endothelial cell line (Ea.hy926) was also tested to assess the safety and selectivity of the compounds towards normal and cancer cells, respectively. Among the compounds tested, compound 2 displayed potent cytotoxic effect (IC50 = 34 μM) against HCT 116 cells with highest selectivity index of 3.1 with respect to the normal endothelial cells. Whereas, compound 4 exhibited significant anti-proliferative effect (IC50 = 21.1 μM) against MCF-7 cells with highest selectivity index of 3.3 with respect to the normal endothelial cells. The docking result of these compounds against hAChE showed potent activities with different binding modes. These compounds could be a promising pharmacological agent to treat cancer and Alzheimer&#39;s disease.

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