BUF52N: Busulfan Hydroxybutyl Sulfonate Impurity

4-Hydroxybutane-1-sulfonic acid sodium salt ;

CAS # 31465-25-5 (Na) ; 26978-64-3 (acid) ;

C4H10O4S (free acid) ; 
Mol. Wt.: 154.18 ;

C4H9NaO4S ;
Mol. Wt.: 176.17 ;