Eman M. Ahmed

Synthesis of novel isatin-thiazoline and isatin-benzimidazole conjugates as anti-breast cancer agents.

A series of new isatin-thiazoline 3a–h and isatin-benzimidazole 4a–h derivatives were synthesized via condensation of isatin Mannich bases 2a–h with either 2-aminothiazoline or 2-aminobenzimidazole. The structures of the newly synthesized compounds were characterized by spectral data. The anti-breast cancer activity of some of the synthesized compounds was assessed in the MCF-7 human breast cancer cell line. The results showed that compounds 4b, 4d and 4g possess significant antiproliferative activity against MCF-7 cells.

Structure-based molecular design, synthesis, and in vivo anti-inflammatory activity of pyridazinone derivatives as nonclassic COX-2 inhibitors

A scaffold with bicyclic core carrying pyridazinone moiety, which exhibited potent in vivo anti-inflammatory activities, was introduced in this article. The design of these compounds was assisted by docking and superposition experiments on cyclooxygenase-2 enzyme. The activity of a chloro analogue was as high as that of diclofenac in carrageenan-induced rat paw edema anti-inflammatory screening.

Synthesis and anti-inflammatory activity of novel pyridazine and pyridazinone derivatives as non-ulcerogenic agents

Herein, we report the synthesis and pharmacological properties of several series of pyridazine and pyridazinone derivatives. All the synthesized compounds were tested, in vivo, for their anti-inflammatory and ulcerogenic properties against indomethacin, as a reference compound. Compounds 4a and 9d have shown a potent anti-inflammatory activity more than indomethacin with rapid onset of action and safe gastric profile. The latter compounds were then selected for further investigation. In the MTT assay in vitro, both compounds were identified as potent and selective COX-2 inhibitors.

Synthesis and biological evaluation of new pyrazolone-pyridazine conjugates as anti-inflammatory and analgesic agents.

A new series of pyrazolone-pyridazine conjugates 3 and 4a-l were synthesized and characterized by spectroscopic means and elemental analyses. All compounds were tested in vivo for their anti-inflammatory and analgesic properties against diclofenac, as reference compound. The synthesized compounds were also evaluated for their ability to inhibit the production of certain inflammatory cytokines such as TNF-α and IL-6 in serum samples. The ulcerogenic potential of the synthesized compounds was also determined. IC50 values for inhibition of COX-1 and COX-2 enzymes were investigated in vitro for the most active candidates. Molecular docking was performed on the active site of COX-2 to predict their mode of binding to the amino acids. Among the synthesized derivatives, compounds 4c and 4e showed good analgesic and anti-inflammatory activities with lower ulcer index than the reference drug.

Synthesis and biological evaluation of novel pyrazoline derivatives as anti-inflammatory and antioxidant agents

A series of novel 5-aryl-3-cyclopropyl-4,5-dihydropyrazole derivatives 2a–p were synthesized via cyclization of chalcones 1a–h with thiosemicarbazide or semicarbazide HCl and evaluated as anti-inflammatory/antioxidant agents. The structures were confirmed by elemental analyses and spectral data. The free radical scavenging activity toward superoxide was determined. Their effect on hepatocytes viability and nitric oxide (NO) production in LPS-stimulated macrophages was also determined. The results showed that compounds 2e and 2n demonstrated the highest free-radical scavenging and anti-inflammatory activities, thus can be useful in the prevention of oxidative stress and inflammation-related disorders.

Design, synthesis and in vitro PDE4 inhibition activity of certain quinazolinone derivatives for treatment of asthma

In this study, a novel series of quinazolinone derivatives analogue to nitraquazone structure were synthesized. The compounds tested for their inhibitory activity against phosphodiesterase 4B revealed that compound 6d shows promising inhibitory activity comparable to that of Rolipram, whereas compounds 6a and 6c exhibited moderate inhibitory activity.

4-Substitutedphthalazines and phthalazinones: synthesis, characterization and β-adrenergic blocking activity

Novel 4-(4-bromophenyl)phthalazine and phthalazinone derivatives connected through 2-propanol spacer to N-substituted piperazine residue were synthesized. All the new compounds were screened for their effect on β-adrenergic blocking activity on the norepinephrine-induced precontracted aortic ring module. Most test compounds displayed appreciable β-adrenolytic activity compared to propranolol as a reference standard. The results have shown that compounds 3a, 3d, 3e and 7c displayed appreciable inhibition of norepinephrine-induced aortic ring contraction.Graphical AbstractA novel 4-(4-bromophenyl)phthalazine and phthalazinone derivatives connected through 2-propanol spacer to N-substituted piperazine residue were synthesized. All new compounds were screened for their effect on β-adrenergic blocking activity on the norepinephrine-induced precontracted aortic ring module.

Design, synthesis, and biological activity of certain quinazolinedione derivatives as potent phosphodiestrase4 inhibitors

In this study, a series of 3-butylquinazolinedione linked with different substituent to N1 of quinazoline nucleus have been synthesized. Some of the new final compounds tested in vitro for their inhibitory activity against phosphodiestrase 4B which is the enzyme responsible for the hydrolysis of cyclic adenosine mono phosphate, the second messenger involved in the regulation of important cell functions. Compound 7f (100%) showed inhibition better than rolipram (90%), while the other tested compounds showed moderate activity. Docking study has been done to rationalize the obtained biological results.

Support Vector Machine ensembles using features distribution among subsets for enhancing microarray data classification

Support Vector Machines (SVMs) ensembles have been widely used to improve classification accuracy in complicated pattern recognition tasks. In this work we propose to apply an ensemble of SVMs coupled with feature-subset selection methods to aleviate the curse of dimensionality associated with expression-based classification of DNA microarray data. We compare the single SVM classifier to SVM ensembles applying two different feature-subset selection techniques, namely random selection and k-means clustering, the base classifiers are combined using either majority vote or SVM fusion. Two real-world benchmarks datasets are used to evaluate and compare the performance. Experimental results show that the SVM ensemble of SVM base classifiers using k-means clustering for feature-subset selection and employing an SVM combiner achieve the best classification accuracy, and that feature-subset-selection methods can have considerable impact on the classification acuracy.

New 3‐Substituted‐2‐(4‐hydroxyanilino)pyridine Derivatives: Synthesis, Antitumor Activity, and Tubulin Polymerization Inhibition

A series of new pyridine derivatives 4a–c, 5a–d, 6a–d, 7a–f, and 8a–f structurally related to ABT‐751 were synthesized and characterized by spectroscopic means and elemental analysis. All the synthesized compounds were tested for their cytotoxic activity in vitro against the HCT‐116 and HepG‐2 cancer cell lines using the MTT assay. The results showed that compound 8d has higher cytotoxic activity than the reference antimitotic agent colchicine, against both tested cell lines, with IC50 = 0.52 and 1.40 μM, respectively. The three most active compounds, 5d, 8b, and 8d, were further screened in vitro for inhibition of tubulin and showed remarkable results in comparison to colchicine.