Background
APHS is an O-acetyl, S-alkyl thio ether of 2-thio phenol. It is a potent inhibitor of both COX-1 and -2, with IC50 values of 17 and 0.8 µM for human recombinant COX-1 and -2, respectively.1 APHS exhibits 20-fold selectivity toward the inhibition of COX-2, yet it is still more potent than aspirin in the inhibition of COX-1. APHS acetylates COX-1 at Ser530 and COX-2 at Ser516 resulting in irreversible enzyme inhibition.1
1.Kalgutkar, A.S., Crews, B.C., Rowlinson, S.W., et al.Aspirin-like molecules that covalently inactivate cyclooxygenase-2Science2801268-1270(1998)