Urea/thiourea derivatives of Gly/Pro conjugated 2,3-dichlorophenyl piperazine as. potent anti-inflammatory agents: SAR studies

Two series of urea/thiourea derivatives of Gly/Pro conjugated 2,3-dichlorophenyl piperazine have been synthesized and characterized as novel anti-inflammatory agents. The results demonstrate that the derivatives if, 1g, 1j, 1k, 2g, 2j and 2k show good anti-inflammatory properties with IC50 values of 42 +/- 0.32 mu M, 30 +/- 0.51 mu M, 65 +/- 0.61 mu M, 60 +/- 0.52 mu M, 60 +/- 0.22 mu M, 57 +/- 0.37 mu M and 35 a 0.15 mu M respectively. These results reveal that compounds with electron withdrawing moieties (F and Cl) particularly at para position exhibit excellent anti-inflammatory activity compared to the standards indomethacin (IC50 = 58 0.371.1 mu M) and ibuprofin (IC50 = 67 +/- 0.43 mu M).