Indomethacin heptyl ester is a potent and selective COX-2 inhibitor with IC50 value of 0.04 μM [1].

The key step in thromboxane and prostaglandin biosynthesis involves the conversion of arachidonic acid to prostaglandin H2 (PGH2), a reaction catalyzed by the cyclooxygenase (COX) and peroxidase activities of prostaglandin endoperoxide synthase or cyclooxygenase. COX is composed of COX-1 and COX-2. COX-2 plays important role in prostaglandin biosynthesis in inflammatory cells and in the central nervous system [1].

Indomethacin is a potent COX-1 and COX-2 inhibitor with IC50 value of 0.05 μM and 0.75 μM, and is also a nonsteroidal antiinflammatory drug. Indomethacin is a substituted indole acetic acid and many of the structurally diverse indomethacin esters and amides show enhanced selectivity for the COX-2 isoform. Indomethacin heptyl ester was more potent and selective COX-2 inhibitor with IC50 value of 0.04 μM and >66 μM for human recombinant COX-2 and COX-1, respectively [1].

Reference:
[1].  Kalgutkar AS, Marnett AB, Crews BC, et al. Ester and amide derivatives of the nonsteroidal antiinflammatory drug, indomethacin, as selective cyclooxygenase-2 inhibitors. J Med Chem. 2000 Jul 27;43(15):2860-70.