Synthesis and bioevaluation of 1-phenyl-pyrazole-4-carboxylic acid derivatives as potent xanthine oxidoreductase inhibitors

1-Phenyl-pyrazole-4-carboxylic acid derivatives were synthesized and evaluated as xanthine oxidoreductase inhibitors. Compound 16c was a mixed-type xanthine oxidoreductase inhibitor with an IC50 of 5.7 nM and a considerable hypouricemic effect similar to febuxostat in mice.160