116686-15-8

Cyclooxygenase (COX) is an intracellular enzyme that converts arachidonic acid into prostaglandin (PG)G2 and PGH2.
The racemic mixtures and the (R)- and (S)-isomers of the 2 metabolites were inactive in the PGE2 test. IC50 values were more than 100 uM for (2 and 5), compared to 1.6 uM for FK 3311 (COX-2 Inhibitor V). Antiinflammatory activity was assessed by inhibition of adjuvant-induced arthritis, and analgesic activity was determined in the acetic acid-induced writhing assay. Following p.o. administration of 10 mg/kg, racemic (2) and its optical isomers showed activity comparable to FK-3311 (76% inhibition) in the adjuvant arthritis test, whereas racemic (5) showed very weak activity, and (R)- and (S)-(5) were not tested. With regard to analgesic effects, FK-3311 and racemic (2) showed 81 and 62% inhibitions, respectively, at a dose of 100 mg/kg p.o. The (R)- and (S)-isomers of (2) and racemic (5) all showed 46% inhibition of writhing syndrome. (R)- and (S)-(5) were less active showing 16 and 20% inhibitions, respectively.

L-PVR, CO, PaO(2), and WDR were significantly better in the FK group than in the control group. Histological tissue edema was mild, and PMN infiltration was significantly reduced in the FK group compared to the control group. The serum TxB(2) levels were significantly lower in the FK group than in the control group, while 6-keto-PGF(1alpha) levels were not significantly reduced. Two-day survival rate was significantly better in the FK group than in the control group.
Survival rate was significantly better and serum GOT levels 30 min after reperfusion were significantly lower in the FK high-dose group compared to the other two groups. Four hours after reperfusion, GPT levels and liver tissue flow were significantly better in the FK high-dose group compared to the control. Both 30 min and 4 hr after reperfusion, serum TxB(2) levels were significantly lower in the FK high-dose group compared to the control.