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Updated: Jun 3, 2026

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Synthesis, X-ray crystal structures and optical properties of novel substituted pyrazoly 1,3,4-oxadiazole derivatives
Hong-Shui Lv1, Yong-Sheng Xie, Wei-Yong Liu
1Institute of Organic Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China.
Abstract:
Novel pyrazoly 1,3,4-oxadiazole derivatives were synthesized and characterized by (1)H NMR, IR, HRMS and X-ray diffraction analysis. UV-vis absorption and fluorescence properties of these compounds in different solutions showed that the maximum absorption wavelength was not significantly changed in different solvents; however, maximal emission wavelength was red-shifted with the increase of solvent polarity. Absorption λ(max) and emission λ(max) was less correlated with substituent groups on aryl rings.
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