Anti-inflammatory activity of 2-acyl-5(3)-hydroxytetrahydro-1H-pyrazole derivatives.

The anti-inflammatory effects of five pyrazolidine derivatives on white mice and laboratory rats were studied using models of thermal aseptic inflammation and inflammation induced by injection of carragenin and histamine, as well as models of "cotton-ball granuloma" and epinephrine (adrenaline)-induced pulmonary edema. These effects were compared with those of the most commonly used non-steroid anti-inflammatory drugs, such as phenylbutazone (CAS 50-33-9) and diclofenac (CAS 15307-79-6). It was found that the pyrazolidine compounds studied induced a pronounced anti-inflammatory effect by inhibiting both the proliferative and exudative phases of inflammation. At the same time, as compared to natural non-steroid anti-inflammatory drugs, these compounds had a lower toxicity and induced neither gastric ulcers nor suppression of hemopoiesis.