methoxy arachidonyl fluorophosphonate methoxy arachidonyl fluorophosphonate methoxy arachidonyl fluorophosphonate, commonly referred as mafp, is an irreversible active site-directed enzyme inhibitor that inhibits nearly all serine hydrolases and serine proteases. it inhibits phospholipase a2 and fatty acid amide hydrolase with special potency, displaying ic50 values in the low-nanomolar range. in addition, it binds to the cb1 receptor in rat brain membrane preparations (ic50 = 20 nm), but does not appear to agonize or antagonize the receptor, though some related derivatives do show cannabinoid-like properties. methoxy arachidonyl fluorophosphonate names preferred iupac name methyl phosphonofluoridate other names mafp identifiers cas number 188404-10-6 n 3d model (jsmol) interactive image chembl chembl113262 y chemspider 8604682 y ec number 201-185-2 pubchem cid 10429254 inchi inchi=1s/c21h36fo2p/c1-3-4-5-6-7-8-9-10-11-12-13-14-15-16-17-18-19-20-21-25(22,23)24-2/h7-8,10-11,13-14,16-17h,3-6,9,12,15,18-21h2,1-2h3/b8-7-,11-10-,14-13-,17-16- ykey: kwkzcgmjghhokj-zkwnwvnesa-n y smiles fp(=o)(oc)cccc\c=c/c\c=c/c\c=c/c\c=c/ccccc properties chemical formula c21h36fo2p molar mass 370.5 except where otherwise noted, data are given for materials in their standard state (at 25 °c , 100 kpa). y verify (what is yn ?) infobox references