1-Propanone, 3-(diethylamino)-1-(4-(ethylthio)phenyl)-2-methyl-, (E)-2-butenedioate (1:1) 3-(Diethylamino)-1-(4-(ethylthio)phenyl)-2-methyl-1-propanone (E)-2-butenedioate (1:1) 69566-91-2