@asu.edu.eg
Prof. Organic Chemistry, chemistry, faculty of science
Ain Shams University
Organic Chemistry, Environmental Chemistry
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Abd El-Azeem El-Sheikh, Ahmed Barakat, Omar Rabiee, Sameh Rizk, Ahmed Kandeil, and Ahmed El Taweel
Egypts Presidential Specialized Council for Education and Scientific Research
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Badriah Alotaibi, Sameh A. Rizk, Haifa A. Alyousef, Ali Atta, and Abdelfattah T. Elgendy
Wiley
Facile synthesis for true intermediate (E)‐ and Z‐2‐(((5‐bromo‐1‐(3‐chloropyridin‐2‐yl)‐1H‐pyrazol‐3‐yl)methylene)amino)‐5‐chloro‐3‐methylbenzoic acid precursors and 2‐(5‐bromo‐1‐(3‐chloropyridin‐2‐yl)‐1H‐pyrazol‐3‐yl)‐6‐chloro‐3,8‐dimethylquinazolin‐4(3H)‐one (QPP) as electron donor/electron acceptor to be working as efficient dye sensitizers. These new derivatives have a wide‐band gap photo‐catalysts semiconductor and are performing to spread to the visible‐light region to give more stability and efficiency towards biomedicine for different diseases. In the present work, the authors are suggesting the design and synthesis of new structures of QPP molecule with extended visible light absorptivity due to the extended π‐π/n‐π conjugations, to stimulate TiO2 nanoparticles in visible‐light region. The physicochemical characterizations confirmed the successful synthesis of QPP, TiO2, and QPP II/TiO2 samples with the proposed structures. Fixing of QPP on the TiO2 surface is refining the optical properties of TiO2 with enhancing the charge separation and generating the efficient antenna in the visible region. Furthermore, the QPP II/TiO2 sample achieved a threefold enhancement in the observed rate constant of the photo‐degradation of rhodamine B dye when compared to the bare TiO2. Finally, the effect of the scavengers was investigated by to be the most reactive species, and the mechanism of the enhancement was suggested for investigation of the proposed structures in various photo‐catalytic and biomedical applications.
Amira A. El-Sayed, Galal A. Elsayed, Sameh A. Rizk, and Mahmoud F. Ismail
Informa UK Limited
Maha Elshazly, Hayam Mahmoud, Amal Saad, Laila Refahy, Mosad Ghareeb, and SAMEH RIZK
Egypts Presidential Specialized Council for Education and Scientific Research
Mahmoud Adel Hamza, Sameh A. Rizk, Ezz-Elregal M. Ezz-Elregal, Shaimaa A. Abd El-Rahman, Sayed K. Ramadan, and Zeinab M. Abou‑Gamra
Springer Science and Business Media LLC
AbstractWater pollution is one of the global threats severely affecting our planet and human health. Organic textile dyes are one of the common organic water pollutants that are presentient to degradation by traditional physical methods. Semiconductor-assisted photocatalysis is considered a green, efficient, and sustainable technology for wastewater treatment. To maximize the efficient utilization of solar radiation, it is of pivotal significance to explore novel organic molecules to be employed as efficient dye sensitizers for wide-bandgap semiconductors to extend their performance to the Visible-light region. Hence, in this work, we are proposing the design and synthesis of novel structures of QAD molecule as a dye photosensitizer with extended visible light absorptivity due to the extended π–π/n–π conjugations, to promote the performance of TiO2 nanoparticles to the visible-light region and enhance the charge separation. The physicochemical characterizations confirmed the successful synthesis of QAD, TiO2, and QAD/TiO2 samples with the proposed structures. The anchoring of QAD molecules on the surface of TiO2 caused a substantial improvement in the optical characteristics of TiO2 as well as overcoming its common drawbacks by decreasing its bandgap energy to 2.6 eV, a remarkable reduction of PL intensity indicating reducing the e–h recombination and enhancing the charge separation, and creation of efficient visible light-harvesting antenna in the range of 400–600 nm. Besides, the QAD/TiO2 sample achieved a 3-fold enhancement in the observed rate constant of the photodegradation of Rhodamine B dye compared to the bare TiO2. The parameters affecting the photodegradation process were optimized and the sample displayed outstanding stability after 4 consecutive cycles. Finally, the effect of the scavengers was investigated and $${\\mathrm{O}}_{2}^{\\cdot -}$$ O 2 · - was proposed to be the most reactive species and the mechanism of the enhancement was suggested based on the electron injection from the QAD’s HOMO level to the TiO2’s CB. Finally, this work opens the door for various studies for the investigation of the proposed structures or similar structures in various photocatalytic/biomedical applications.
Mona A. Shalaby, Asmaa M. Fahim, and Sameh A. Rizk
Springer Science and Business Media LLC
AbstractIn this investigation, pressure microwave irradiation was used to clarify the activity of 1-(2-hydroxyphenyl)-3-(4-methylphenyl)prop-2-en-1-one (3) towards several active methylene derivatives utilized the pressurized microwave irradiation as green energy resource . Chalcone 3 was allowed to react with ethyl cyanoacetate, acetylacetone, and thioglycolic acid; respectively, at 70 °C with pressure under microwave reaction condition to afford the corresponding 2-hydroxyphenylcyanopyridone, 2-hydroxyphenyl acetylcyclohexanone, and thieno[2,3-c]chromen-4-one derivatives respectively. Moreover, the reaction of chalcone 3 with hydrogen peroxide with stirring affords the corresponding chromen-4-one derivative. All the synthesized compounds were confirmed through spectral tools such as FT-IR, 1HNMR, 13CNMR, and mass spectrum. Furthermore, the synthesized heterocycles were exhibited excellent antioxidant activity and comparable with vitamin C, where the presence of the OH group increases the scavenger radical inhibition. Furthermore, the biological activity of compound 12 was demonstrated through molecular docking stimulation using two proteins, PDBID: 1DH2 and PDBID: 3RP8, which showed that compound 12 possesses greater binding energy and a shorter bond length comparable with ascorbic acid. Also, the compounds were optimized through DFT/B3LYP/6-31G (d,p) basis set and identification of their physical descriptors, whereas the compound 12 was confirmed through X-Ray single structure with Hirsh field analysis of the compound to know the hydrogen electrostatic bond interaction, and correlated with the optimized structure by comparing their bond length, bond angle, FT-IR, and NMR, which gave excellent correlation.
Ashraf Ashmawy, amr Alahl, Ali A.Ali, Ammar Mahmoud, and sameh rizk
Egypts Presidential Specialized Council for Education and Scientific Research
Mona A. Shalaby, Sameh A. Rizk, and Asmaa M. Fahim
Royal Society of Chemistry (RSC)
Chalcones, Reactions, Synthesis, Biological activity, Industrial application.
Ayman M. Algohary, A. M. A. Hassan, Abdullah Y. Alzahrani, and Sameh A. Rizk
Wiley
Mona A. Shalaby, Asmaa M. Fahim, and Sameh A. Rizk
Royal Society of Chemistry (RSC)
Heterocyclic scaffolds are frequently employed in drug development to treat a variety of conditions, including cancers.
sameh rizk and Mohamed El Sayed Alya
Egypts Presidential Specialized Council for Education and Scientific Research
Eman Abdel-Nasser et al.
Egypts Presidential Specialized Council for Education and Scientific Research
Alshimaa E. Nassar, Eslam Ibrahim El-Aswar, Sameh A. Rizk, Seleem El-Sayed Gaber, and Hossam S. Jahin
Elsevier BV
Mohammed Abed Kadhim, Amin Farouk Mohamed Fahmy, Emad Khelil Mohammed Zangana, Aya Ibrahim Hassaballah, and Sameh Ahmed Rizk
Universitas Gadjah Mada
5,6,7,8-Tetrahydroquinazolin-2-(thio)-ones (THQ) fits the class of N-heterocycles as a structural core in numerous bioactive compounds. They promptly extended previous decades. They were significantly recognized in combinatorial chemistry and materials science to determine the drug discovery, antioxidants, and pharmaceuticals fields. In the present work, one-pot multicomponent sustainable synthesis of THQ with easily accessible starting materials, i.e., cyclohexanone, different aromatic aldehydes and (thio)urea, has been performed to determine the proposed Biginelli mechanism that is supported by DFT. It is found that the THQs are synthesized by a mechano-chemical (grinding) tool to achieve a yield of 85.2% within 3.5 min, i.e., YE (% yield/time) 24.34 differs from the conventional method in which lower % yield (YE = 0.72) of THQ was achieved. This confirmed that in the green chemistry principle, the determination of % yield according to saving reaction time must be considered. Moreover, DFT-based antioxidant properties of the THQ were also studied in which the most potent antioxidant compounds were 7b > 6d > 2f. Softness (σ, eV−1) and hardness (η, eV mol−1) can approve the soft molecule that stays more reactive as a result of decreasing the energy gap along heterocyclic with values 0.1491 > 0.1300 > 0.1168 eV−1 one-to-one with the efficiency of antioxidant.
Sameh A. Rizk, Abdullah Y. Alzahrani, and Abdullah M. Abdo
Informa UK Limited
Eman A. E. El-Helw, Aya M. Abdelrahman, Abdelgawad A. Fahmi, and Sameh A. Rizk
Informa UK Limited
Ahmad Baraka, Mohamed Sheashea, Karim Gado, Sameh Rizk, and Osama Abuzalat
Wiley
Aya M. Abdelrahman, Abdelgawad A. Fahmi, Eman A. E. El-Helw, and Sameh A. Rizk
Informa UK Limited
Mohamed M. Kaddah, Abdelgawad A. Fahmi, Mustafa M. Kamel, Sameh A. Rizk, and Sayed K. Ramadan
Informa UK Limited
Abstract It was well known that hydrazine–hydrazone derivatives have an important role in different synthetic and medicinal fields. Therefore, the hydrazide–hydrazone derivative 3 was treated with electrophilic reagents achieving some quinoline-based heterocyclic systems such as chromene and pyridine derivatives and screened for their rodenticidal activity. The potent compounds were subjected to density functional theory studies. Seven compounds were tested for hemorrhoidal activity. Compounds 5, 6, and 7 were more effective against rodents than the other synthesized compounds, which were controlled by the most potent active second-generation products, such as chlorophacinone, brodifacoum, and warfarin. This could be attributed to their existence in more tautomeric structures. As a result, they could be used as rodenticides. Graphical Abstract
Aya I. Hassaballah, Sayed K. Ramadan, Sameh A. Rizk, Eman A. E. El-Helw, and Salwa S. Abdelwahab
Informa UK Limited
Abstract Ultrasonic and solvent-free condensation of 2-aminobenzoic acid with 4-bromoisobenzofuran-1,3-dione to construct the 4′-bromo-3′H-spiro[benzo[d][1,3]-oxazine-2,1′-isobenzofuran]-3′,4(1H)-dione dye (1) under basic reaction conditions. The spiro product 1 exhibited both electrophilic and nucleophilic centers. A series of nitrogen nucleophiles such as hydrazine, glycine, 2-aminopyridine, pyridin-2-ylmethanamine, 4-methoxyaniline, 4-aminoacetophenone, morpholine, piperidine or 1-ethylpiperazine and carbon electrophiles such as oxiranylmethylchloride, ethyl chloroacetate, chloroacetyl chloride can be treated with 2-benzoxazine-2-yl benzoic acid (BBA) via multicomponent reaction. The fluorescence of the spiro product dyes decreases proportionally to the initial chloride concentration in the solution. The chemical structures of the synthesized compounds can be confirmed by microanalytical, spectral data and optimized by quantum chemical parameters. Biological evaluation showed that these synthesized spiro compounds exhibited moderate to good cytotoxic activity. Among them, compounds 2, 5, and 11 displayed the best cytotoxic activity against MCF7 and Wl-38 cell lines.
Sameh A. Rizk, Salwa S. Abdelwahab, and Abdullah M. Abdo
Informa UK Limited
Abstract The present work described a novel synthesis of spiro[indoline-3,3′-pyrazol]-2-one derivatives 2, 4, 5, and 7 via a one-pot reaction of chalcones or β-aroyl acrylic acid 1a–c, isatin, and hydrazine derivatives e.g. hydrazine hydrate, methyl hydrazine, phenylhydrazine or acetohydrazide in sonicated reaction condition. The unexpected product 1,3-oxazino[3,2-a]indol-10-yl-ethanone derivative 6 can be generated instead of N-acetyl spiro[indoline-3,3′-pyrazol]-2-one as desired. Also, the Spiropyrazole-fused furanone and pyridazinone ring can be made. Owing to their unique 3-dimensional structures, spirooxindoles have been found as lucky chemotypes for antiviral drug enhancement in an attempt to achieve these spiropyrazole derivatives 2–10 with hydrophobic groups. Furthermore, the density functional theory (DFT) was used to elucidate the electronic and structural features of spiropyrazole derivatives and their reactive species, which supports the proposed mechanism of antibacterial and antiviral capabilities.
Aya M. Abdelrahman, Abdelgawad A. Fahmi, Sameh A. Rizk, and Eman A. E. El-Helw
Informa UK Limited
Abstract The broad spectrum of biological activity of pyrazole derivatives coupled with our interest in the chemistry of nitrogen heterocycles led us to synthesize a bis-benzoxazinone derivative bearing a pyrazole scaffold and utilize it as a key material for the construction of some bisimidazole, bistriazole, and bisbenzimidazole derivatives obtained by reactions with some mono- and bidentate nitrogen nucleophiles. The density functional theory studies of the synthesized compounds were calculated. The synthesized compounds were screened for their in vitro antitumor activity against two human tumor cell lines; HepG2 and MCF-7. Some compounds displayed satisfactory activities.
Mona A. Shalaby, Hamad M. Al-Matar, Asmaa M. Fahim, and Sameh A. Rizk
Elsevier BV
F. H. Mahmoud Naglaa, Sameh A. Rizk, A. Elsayed Galal, and Ali Kh. Ali
Springer Science and Business Media LLC
AbstractA rapid and efficient microwave-promoted one-pot strategy has been utilized to synthesize differentially functionalized spiro[indoline-3,4′-pyrazolo[3,4-b] pyridine derivatives. Different optimized reaction conditions have been exploited when one-pot four-component (hydrazines, 1,3-dicarbonyl compounds, isatin, and malononitrile) reactions took place to afford satisfying yields of compounds [5–28]. Among different methodologies, the catalyst-free microwave-assisted fusion process has been proved to be the strategy with desirable traits to give good-to-excellent yields of the target compounds. Structural features of the obtained compounds were confirmed by the basis of elemental analyses, mass,1H-NMR, and13C-NMR spectrometry.