Synthesis and anti-inflammatory activity of some potential cyclic phenothiazines.

Some new schiff's bases (IVa-IVe), thiazolidinones (Va-Ve), delta 2-triazolines (VIa-VIe) and formazans (VIIa-VIIe) of 2-chlorophenothiazine have been synthesized and screened against Carrageenin induced oedema in albino rats. Some compounds of the series have shown promising activity. The most active compound is 2-chloro-10[5-(2-fluorophenyl-2-oxo-4 thiazolidin-1-yl)-amino acetyl] phenothiazine was found to be most potent. This compound (Vb) was further evaluated in detail and compared with phenylbutazone for its relative anti inflammatory potency (ED50), ulcerogenic liabilities (UD50) and acute toxicity (ALD50). It was found to be almost comparable to phenylbutazone as regards anti-inflammatory activity was concerned but and minimum ulcerogenic liability and cardiovascular effects. Hence, it seems promising as an anti-inflammatory agent in our preliminary studies.