155156-22-2 3-alpha-Tropanyl 2-(4-chlorophenoxy)butyrate 3-alpha-Tropanyl-(2-Cl)-acid phenoxybutyrate Butanoic acid, 2-(4-chlorophenoxy)-, 8-methyl-8-azabicyclo(3.2.1)oct-3-yl ester, (3(R)-endo)-, (Z)-2-butenedioate (1:1) Butanoic acid, 2-(4-chlorophenoxy)-, endo-8-methyl-8-azabicyclo(3.2.1)oct-3-yl ester, (2R)-, (2Z)-2-butenedioate (1:1) Butyric acid, 2-(4-chlorophenoxy)-, 3-alpha-tropanyl ester SM 21 SM(21)