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Updated: Dec 1, 2025

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Crystal Growth, Single Crystal Structure, and Biological Activity of Thiazolo-Pyridine Dicarboxylic Acid Derivatives
Hamdi Ben Yahia1, Souhir Sabri1, Rachid Essehli2
1Qatar Environment and Energy Research Institute (QEERI 2.0), Hamad Bin Khalifa University, Qatar Foundation, P.O. Box 34110 Doha, Qatar.
Abstract:
Four novel TPDCA derivatives were prepared via a supersaturation method combining TPDCA with water, N-methyl-2-pyrrolidone (NMP), Na(PO2H2), and ammonia solution: 2(C9H7NO5S)H2O (1), (C9H7NO5S)C5H9NO (2), (C9H7NO5S)Na(PO2H2) (3), and (C9H5NO5S)(NH4)2(H2O) (4). Their crystal structures were determined by single-crystal X-ray diffraction. Compounds (1) and (2) crystallize in the monoclinic space groups P21 and P21/c, respectively, whereas compounds (3) and (4) crystallize in the triclinic space group P1̅. Weak and moderate hydrogen bonds were detected in the four compounds. In the biological tests, (1) and (3) exhibited significant antibacterial activity against Escherichia coli and Staphylococcus aureus; in addition, (1) was cytotoxic against leukemia HL-60 cells with the IC50 value of 158.5 ± 12.5 μM.
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