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    Advances in the chemical and biological diversity of heterocyclic systems incorporating pyrimido[1,6-a]pyrimidine and pyrimido[1,6-c]pyrimidine scaffolds
    (Royal Soc Chemistry, 2020) Elattar, Khaled M.; Mert, Basak Dogru; Monier, M.; El-Mekabaty, Ahmed
    Heterocycles incorporating a pyrimidopyrimidine scaffold have aroused great interest from researchers in the field of medical chemistry because of their privileged biological activities; they are used as anti-bacterial, antiviral, anti-tumor, anti-allergic, antihypertensive, anticancer, and hepatoprotective agents. Therefore, the present study aims to investigate the chemistry of heterocycles incorporating pyrimido[1,6-a]pyrimidine and pyrimido[1,6-c]pyrimidine skeletons and their biological characteristics. The main sections discuss (1) the synthetic routes to obtain substituted pyrimidopyrimidines, pyrimido[1,6-a]pyrimidin-diones, pyrimidoquinazolines, tricyclic, tetracyclic, and binary systems; (2) the reactivity of the substituents attached to the pyrimidopyrimidine skeleton, including thione and amide groups, nucleophilic substitutions, condensations, ring transformations, and coordination chemistry; (3) compounds of this class of heterocycles containing a significant characteristic scaffold and possessing a wide range of biological characteristics.
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    Advances in the Chemistry of 6-6 Bicyclic Systems: Chemistry of Pyrido[3,4-d]pyrimidines
    (Bentham Science Publ Ltd, 2019) Monier, Mohamed; Abdel-Latif, Doaa; El-Mekabaty, Ahmed; Mert, Basak D.; Elattar, Khaled M.
    The aim of this work is to discuss the chemistry of pyrido[3,4-d]pyrimidines as one of the most important heterocyclic compounds with remarkable synthetic, biological and medical applications. In this overview, the chemistry of hetemcyclic compounds incorporated the pyrido[3,4-d]pyrimidine scaffold as demonstrated by chemical reactions and different preparation processes. The anticipated compounds were synthesized from pyridine or pyrimidine compounds and a description of the reactivity of substituents attached to ring carbon and nitrogen atoms is discussed. On the other hand, the synthesis and reactions of fused heterocycles incorporated pyrido[3,4-d]pyrimidine scaffold is described. The diamine analogs included pyrido[3,4-d]pyrimidine core were reported as tyrosine kinase inhibitors. The chemical reactions of certain unexpected and chemically substantial compounds have been discussed.
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    Experimental and computational study of a solar-powered electrolysis system with a SEPIC converter for green hydrogen production
    (Pergamon-Elsevier Science Ltd, 2025) Nazligul, Huseyin; Mert, Mehmet Erman; Edis, Cansu; Demir, Beyza Nur; Gurdal, Yeliz; Elattar, Khaled M.; Mert, Basak Dogru
    The study presents an integrated approach for sustainable hydrogen production by coupling a photovoltaic system with an alkaline electrolysis unit optimized for fluctuating solar conditions. The catalyst for the electrolysis system was NiCoMo-modified Ni foam, which was created using a two-stage galvanostatic procedure that involved Ni and Co deposition followed by Mo enrichment. Electrochemical tests such were used to verify the catalytic activity of alkaline electrolysis. The device produced 120.2 mL of hydrogen in 30 min at 3 V, with a Faradaic efficiency of around 93.6 %, showing suitable electrochemical efficiency. To ensure stable electrolysis operation, a SEPIC DC-DC converter was integrated into the system, managed by real-time maximum power point tracking algorithms-Particle Swarm Optimization, Genetic Algorithm, and Artificial Bee Colony-modeled using 2023 solar irradiance data from Adana, Turkey. The ABC algorithm demonstrated the fastest convergence performance. The SEPIC converter successfully stabilized the output voltage at 7.5 V despite daily and seasonal battery voltage variations, maintaining optimal catalyst operating conditions. In the theoretical part of the study, a Co and Mo-doped Ni surface was constructed, and water adsorption on the most stable surface was examined using Density Functional Theory (DFT). Computational examination of the electrical structure revealed that Mo atoms contribute significantly more to the alloy matrix than Ni and Co. DFT calculations found that the oxygen atom of the water molecule adsorbs on top of the Mo atom at an adsorption energy of -1.03 eV. Mo doping on the Ni(111) surface directly enhances the strength of water adsorption.
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    Green Synthesis of MoNi@TiO2 Nanocatalyst for Efficient Methanol Oxidation: Structural, Morphological, and Electrochemical Insights
    (Wiley-VCH GmbH, 2025) Mert, Mehmet Erman; Mert, Basak Dogru; Elattar, Khaled M.
    This study presents a novel, green approach for synthesizing MoNi@TiO2 core-shell nanocomposites as efficient electrocatalysts for direct methanol fuel cells (DMFCs). The use of Curcuma longa extract as a bioreduction and stabilizer agent for the synthesis of the nanocatalyst offers an eco-friendly alternative to traditional synthetic methods. Characterization confirms the successful formation of well-defined core-shell structures with a narrow size distribution and minimal organic residue. Remarkably, the presence of specific Mo/Ni oxide phases alongside anatase and rutile TiO2 in the shell verified unique catalytic properties. The developed Ni/MoNi@TiO2 electrocatalyst demonstrates promising electrocatalytic activity for methanol oxidation, comparable to or even surpassing established transition metal catalysts such as Pt-based catalysts, offering a promising alternative for DMFC applications. The concentration-dependent peak current density further highlights its potential for efficient DMFC operation. This work demonstrates the feasibility and advantages of using bio-inspired synthesis for developing sustainable and high-performance electrocatalysts for energy conversion applications.
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    Heterocyclic steroids: Efficient routes for annulation of pentacyclic steroidal pyrimidines
    (Elsevier Science Inc, 2020) Monier, M.; El-Mekabaty, Ahmed; Abdel-Latif, Doaa; Mert, Baak Dogru; Elattar, Khaled M.
    Steroids are components of cell membranes, signaling molecules and are a type of secondary metabolites as a result of their high impact of biological significance. The present review described the literature reports of pentacyclic steroidal pyrimidines as a type of heterocyclic steroids. The main sections included the synthesis of the investigated steroids fused at rings-A or B or D of steroid skeleton, synthesis of binary or linked-type pyrimidines, pyrimidine oxides, macromolecules and mono- or di- or hi-peptides linked-steroidal pyrimidines. Besides, the present research highlighted the biological significance of steroidal pyrimidines, in which the compounds revealed potent anticancer, antioxidant, antibacterial, and anti-Alzheimer agents. In addition, some hetero-steroids were screened for binding DNA assay and gene expression analysis. It was settled that the incorporation of pyrimidine scaffold into steroid basic skeleton is crucial for better biological results.