319SYNTHESIS CHARACTERIZATION AND PHARMACOLOGICAL EVALUATION OF SOME PYRAZOLIDINEDIONE SUBSTITUTED THIOCROMENE DERIVATIVES AS ANTI-INFLAMMATORY AGENTSAll the newly synthesized compounds were characterized by their physical properties and spectral data. The purity of newly synthesized compounds was confirmed by TLC. Spectral analysis (IR, 1H, 13C NMR and Mass spectrometry) of the compounds adequately supported the structures of the synthesized compounds. The appearance of a band between 1764-1623 cm-1 (C=O) in the IR spectra; a singlet peak at ? value 4.3-5.0 for two protons of CH2 of the pyrazolidinedione ring in the 1H NMR spectra and a peak at ? 41.7-46.9 for carbon of CH2 of the pyrazolidinedione ring supports the formation of pyrazolidinedione substituted thiochromene derivatives (20-35). Molecular ion peaks of the synthesized pyrazolidinedione substituted thiochromene derivatives were obtained on the mass spectra, corresponds with their structures. These spectral data satisfactorily supports the formation of the title compounds. The formation of thiochromene and pyrazolidinedione moieties is supported by the reaction mechanismketki492@gmail.comResearch1422024 Pyrazolidinedione Ring, Anti-Inflammatory, Synthesis, TLC, NMR.Lucky Tiwari1, Ketkee Mandawar1*, Vibha Devi, Nishi Prakash Jain1RKDF College of Pharmacy, Bhopal