It was reported in a previous paper that No. 2 compound had a similar effect to flufenamic acid (FA) on acute experimental inflammation and the No. 1 compound which was substituted carbonic acid of No. 2 to acetic acid had a more potent effect than FA. In this paper, the effects of title compounds on subacute experimental inflammation are described in comparison with such known anti-inflammatory agents as FA, mefenamic acid (MA), phenylbutazone (PB) and indomethacin (IM).
On sustained mustard edema, granuloma tissue formation (cotton pellet, granuloma pouch and wound healing) and adjuvant arthritis, No. 2 showed a similarly inhibitory effect to FA and PB, while No. 1 showed a more potent effect than No. 2 and FA and similar to IM. Both No. 1 and No. 2 compounds had a more potently inhibitory effect on subacute infiammation than on the acute. In these anti-inflammatory activities, no significant difference was observed between free and sodium salt, but No. 1 was several times more potent than No. 2 as on acute inflammation as well. Neither compound showed a direct analgesic or uricosuric effect, but indirectly an analgesic effect was observed, due to an anti-inflammatory action. From the potent effect on subacute inflammation and in addition, a markedly inhibitory effect on carrageenin edema and ultraviolet erythema, test compounds, in particular No. 1, may be considered effective on such chronic inflammation as rheumatic disease, while toxicity and ulcerogenic action were found to be stronger than FA and PB.