Synthesis and Biological Evaluation of Coumarin-Linked 4-Anilinomethyl-1,2,3-Triazoles as Potent Inhibitors of Carbonic Anhydrases IX and XIII Involved in Tumorigenesis

A series of coumarin-linked 4-anilinomethyl-1,2,3-triazoles (6a–t) was synthesized via a molecular hybridization approach, through carbon C-6 of the coumarin moiety. The synthesized compounds were evaluated for their inhibition of carbonic anhydrase (CA) isoforms I, II, IX and XIII. CAs IX and XIII were selectively inhibited over the off-target isoforms I and II. The best inhibitory profiles against CA IX were shown by compounds 6a, 6e and 6f (K(i) < 50 nM), with compound 6e displaying the best inhibition with a K(i) value of 36.3 nM. Compounds 6a, 6b, 6j, 6o and 6q exhibited the best inhibitory profiles against CA XIII (K(i) < 100 nM). These compounds can be further explored for the discovery of potent and effective CA IX and CA XIII inhibitors.