Hyoscine butylbromide Imp D (EP): (1R,2R,4S,5S,7s,9r)-7-[[(2S)-3-hydroxy-2-phenylpropanoyl]oxy]-9-methyl-9-propyl-3-oxa-9-azoniatricyclo[3.3.1.02,4]nonane (propylhyoscine).