1-Hydroxypyrazole as a bioisostere of the acetic acid moiety in a series of aldose reductase inhibitors.

Therapeutic intervention with aldose reductase inhibitors appears to be promising for major pathological conditions (i.e., long-term diabetic complications and inflammatory pathologies). So far, however, clinical candidates have failed due to adverse side-effects (spiroimides) or poor bioavailability (carboxylic acids). In this work, we succeeded in the bioisosteric replacement of an acetic acid moiety with that of 1-hydroxypyrazole. This new scaffold appears to have a superior physicochemical profile, while attaining inhibitory activity in the submicromolar range.