Levalbuterol Hydrochloride: C~13~H~21~NO~3~ HCl. Mw: 275.77. (R) – α^1^-[(tert-Butylamino)methyl]-4-hydroxy-m-xylene – α, α’-diol hydrochloride. CAS-50293-90-8 (1997).
Levalbuterol Tartrate: 2(C~13~H~21~NO~3~) C~4~H~6~O~6~. Mw: 628.71. 1,3-Benzenedimethanol, α^1^-[[(1,1-dimethylethyl)amino]methyl]-4-hydroxy-, (α^1^R)-, (2R,3R)-2,3-dihydroxybutanedioate (2:1). CAS-661464-94-4 (2004).