Clopidogrel EP Impurity B HCl (S-Isomer) Catalogue L620413 CAS 1396607-35-4 M.W 321.82 36.46 M.F C16H16ClNO2S. HCl Specifications FAQs Methyl (S)-2-(2-chlorophenyl)-2-(4,7-dihydrothieno[2,3-c]pyridin-6(5H)-yl)acetate, hydrochloride (1:1)