A series of phenols incorporating tertiary amine and trans-pyridylethenyl-carbonyl moieties were assayed as inhibitors of the beta-carbonic anhydrase (CA, EC 4.2.1.1) from Saccharomyces cerevisiae, ScCA. One of these compounds was a low nanomolar ScCA inhibitor, whereas the remaining ones inhibited the enzyme with K(I)s in the range of 23.5-95.4 nM. The off-target human (h) isoforms hCA I and hCA II were much less inhibited by these phenols, with K(I)s in the range of 0.78-23.5 mu M (hCA I) and 10.8-52.4 mu M (hCA II). The model organism S. cerevisiae and this particular enzyme may be useful for detecting antifungals with a novel mechanism of action compared to the classical azole drugs to which significant drug resistance emerged.
