3,4-dihydroxystyrene 3,4-dihydroxystyrene 3,4-dihydroxystyrene (dhs) is a centrally-acting inhibitor of the enzyme phenylalanine hydroxylase (ph). it is likely that dhs and other ph inhibitors will never have clinical applications on account of their capacity for inducing hyperphenylalaninemia and phenylketonuria. 3,4-dihydroxystyreneclinical dataatc codenonelegal statuslegal status in general: uncontrolled identifiers iupac name 4-ethenylbenzene-1,2-diol cas number6053-02-7 npubchem cid151398chemspider133430 yunii28c0i29e70keggc06224 ycomptox dashboard (epa)dtxsid20209275 chemical and physical dataformulac8h8o2molar mass136.150 g·mol−13d model (jsmol)interactive image smiles oc1ccc(\c=c)cc1o inchi inchi=1s/c8h8o2/c1-2-6-3-4-7(9)8(10)5-6/h2-5,9-10h,1h2 ykey:fbtsutgmwbdaac-uhfffaoysa-n y ny (what is this?) (verify)