Synthesis of sulfonamide-containing N-hydroxyindole-2-carboxylates as inhibitors of human lactate dehydrogenase-isoform 5

N-Hydroxyindole-2-carboxylates possessing sulfonamide-substituents at either position 5 or 6 were designed and synthesized. The inhibitory activities of these compounds against isoforms 1 and 5 of human lactate dehydrogenase were analysed, and K-i values of the most efficient inhibitors were determined by standard enzyme kinetic studies. Some of these compounds displayed state-of-the-art inhibitory potencies against isoform 5 (K-i values as low as 5.6 mu M) and behaved as competitive inhibitors versus both the substrate and the cofactor. (C) 2011 Elsevier Ltd. All rights reserved.