Synthesis of Asymmetric Thiazolyl Pyrazolines as a Potential Antioxidant and Anti-Inflammatory Agents RautDattatraya G. LawandAnjana S. KaduVikas D. HublikarMahesh G. PatilSandeep B. BhosaleDnyandev G. BhosaleRaghunath B. 2020 <p>A new series of 1-Thiazolyl-2-Pyrazolines <b>5a-g</b> was accomplished by reacting pyrazolealdehyde with an appropriate aromatic ketone in the presence of PEG-300 as a solvent to yield chalcone. The chalcones reacted with thiosemicarbazide to yield asymmetric 1-thiocarbamoyl pyrazoles. The above formed 1-thiocarbamoyl pyrazoles reacted with appropriate α- haloketones to yield 1-Thiazolyl-2-Pyrazolines. The structural interpretations of newly formed compounds were done by <sup>1</sup>H NMR, <a href="#CIT0013" target="_blank"><sup>13</sup></a>CNMR, IR and mass spectroscopic methods. The newly prepared asymmetric 1-Thiazolyl-2-pyrazoline derivatives were evaluated to their <i>in vitro</i> antioxidant (H<sub>2</sub>O<sub>2</sub>, DPPH, SOR and NO radical inhibiting activity) as well as anti-inflammatory activity. The 1-Thiazolyl-2-pyrazoline derivatives <b>5a-g</b> exhibited moderate to good H<sub>2</sub>O<sub>2</sub> scavenging activity as match up to ascorbic acid. All the 1-Thiazolyl-2-pyrazoline derivatives exhibited excellent SOR scavenging activity except <b>5 b</b>. All the tested compounds have shown good to excellent, NO radical inhibiting activity. DPPH radical scavenging activity results have shown low antioxidant activity. Also, all the 1-Thiazolyl-2-pyrazoline derivatives were tested for their <i>in vitro</i> anti-inflammatory activity. The compounds <b>5a</b>, <b>5 b</b>, <b>5c, 5f</b> and <b>5 g</b> were exhibited good anti-inflammatory activity and <b>5d</b> showed moderate activity while <b>5e</b> less active as match up to diclofenac sodium as a standard reference.</p>