pd-0298029 pd-0298029 pd-0298029 is a drug which acts as a selective antagonist for the muscarinic acetylcholine receptor m4. it was developed for the treatment of parkinson's disease, but poor bioavailability and rapid metabolism in animal studies have meant its use is largely limited to in vitro research into the m4 and other muscarinic receptors. pd-0298029identifiers iupac name ethyl 3,6a,11,14-tetrahydro-9-methoxy-2-propyl-3,5-dimethyl-(12h)-isoquinopyrrolobenzoxazine-1-carboxylate chemspider26233369 ychemical and physical dataformulac27h32n2o4molar mass448.563 g·mol−13d model (jsmol)interactive imageinteractive image smiles cccc1c(c2c(n1c)cc(c3c2cn4ccc5cc(ccc5c4o3)oc)c)c(=o)occcccc1n(c)c5cc(c)c3oc4c2ccc(oc)cc2ccn4cc3c5c1c(=o)occ inchi inchi=1s/c27h32n2o4/c1-6-8-21-24(27(30)32-7-2)23-20-15-29-12-11-17-14-18(31-5)9-10-19(17)26(29)33-25(20)16(3)13-22(23)28(21)4/h9-10,13-14,26h,6-8,11-12,15h2,1-5h3 ykey:mtmzsgqxrvrksy-uhfffaoysa-n y (verify)